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IREAU  OF  INDIAN  STANDARDS 


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NATIONAL  BUILDING  CODE 
OF  INDIA  201 6  x 

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2 


NATIONAL  BUILDING  CODE 
OF  INDIA  2016 

VOLUME  2 


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BUREAU  OF  INDIAN  STANDARDS 


SP  7  :  2016 

FIRST  PUBLISHED  1970 
FIRST  REVISION  1983 
SECOND  REVISION  2005 
THIRD  REVISION  2016 

©  BUREAU  OF  INDIAN  STANDARDS 

ICS  01.120;  91.040.01 


PRICE  ? 


PUBLISHED  BY  BUREAU  OF  INDIAN  STANDARDS,  MANAK  BHAVAN,  9  BAHADUR  SHAH  ZAFAR 
MARG,  NEW  DELHI  110002;  TYPESET  AT  SUNSHINE  GRAPHICS,  263,  TELIWARA,  SHAHDARA,  DELHI 
1 1 0032;  PRINTED  AT  J.  J.  OFFSET  PRINTERS,  A-24,  SECTOR  68,  NOIDA,  GAUTAM  BUDH  NAGAR,  UTTAR 
PRADESH  (INDIA). 


CONTENTS 


Volume  1 

Foreword  ...  (v) 

Committee  Composition  ...  (ix) 

Important  Explanatory  Note  for  Users  of  the  Code  ...  (xxx) 

Information  for  the  Users  about  Availability  of  the  Code  in  Groups  ...  (xxxi) 

Total  Pages 

Part  0  Integrated  Approach  —  Prerequisite  for  Applying  Provisions  of  the  Code  ...  12 

Part  1  Definitions  ...  28 

Part  2  Administration  ...  32 

Part  3  Development  Control  Rules  and  General  Building  Requirements  ...  150 

Part  4  Fire  and  Life  Safety  ...  116 

Part  5  Building  Materials  ...  46 

Part  6  Structural  Design 

Section  1  Loads,  Forces  and  Effects  ...  134 

Section  2  Soils  and  Foundations  ...  60 

Section  3  Timber  and  Bamboo 

3A  Timber  ...  56 

3B  Bamboo  ...  30 

Section  4  Masonry  ...  86 

Section  5  Concrete 

5 A  Plain  and  Reinforced  Concrete  ...  118 

5B  Prestressed  Concrete  ...  52 

Section  6  Steel  ...  138 

Section  7  Prefabrication,  Systems  Building  and  Mixed/Composite  Construction 

7A  Prefabricated  Concrete  ...  42 

7B  Systems  Building  and  Mixed/Composite  Construction  ...  12 

Section  8  Glass  and  Glazing  ...  80 

Volume  2 

Important  Explanatory  Note  for  Users  of  the  Code  ...  (iv) 

Information  for  the  Users  about  Availability  of  the  Code  in  Groups  ...  (v) 

Total  Pages 

Part  7  Construction  Management,  Practices  and  Safety  ...  76 

Part  8  Building  Services 

Section  1  Lighting  and  Natural  Ventilation  ...  56 

Section  2  Electrical  and  Allied  Installations  ...  172 

Section  3  Air  Conditioning,  Pleating  and  Mechanical  Ventilation  ...  86 

Section  4  Acoustics,  Sound  Insulation  and  Noise  Control  ...  46 

Section  5  Installation  of  Lifts,  Escalators  and  Moving  Walks 

5  A  Lifts  ...  96 

5B  Escalators  and  Moving  Walks  ...  44 

Section  6  Information  and  Communication  Enabled  Installations  ...  28 

Part  9  Plumbing  Services  (Including  Solid  Waste  Management) 

Section  1  Water  Supply  ...  44 

Section  2  Drainage  and  Sanitation  ...  82 

Section  3  Solid  Waste  Management  ...  16 

Section  4  Gas  Supply  ...  18 

Part  10  Landscape  Development,  Signs  and  Outdoor  Display  Structures 

Section  1  Landscape  Planning,  Design  and  Development  ...  34 

Section  2  Signs  and  Outdoor  Display  Structures  ...  24 

Part  11  Approach  to  Sustainability  ...  98 

Part  12  Asset  and  Facility  Management  ...  98 

(hi) 


Important  Explanatory  Note  for  Users  of  the  Code 

In  any  Part/Section  of  this  Code,  where  reference  is  made  to  ‘good  practice’  in 
relation  to  design,  constructional  procedures  or  other  related  information,  and  where 
reference  is  made  to  ‘accepted  standard’  in  relation  to  material  specification, 
testing,  or  other  related  information,  the  Indian  Standards  listed  at  the  end  of  the 
Part/Section  shall  be  used  as  a  guide  to  the  interpretation. 

At  the  time  of  publication,  the  editions  indicated  in  the  standards  were  valid.  All 
standards  are  subject  to  revision  and  parties  to  agreements  based  on  any  Part / 
Section  are  encouraged  to  investigate  the  possibility  of  applying  the  most  recent 
editions  of  the  standards. 

In  the  list  of  standards  given  at  the  end  of  a  Part/Section,  the  number  appearing 
within  parentheses  in  the  first  column  indicates  the  number  of  the  reference  of  the 
standard  in  the  Part/Section.  For  example: 

a)  Good  practice  [7(2)]  refers  to  the  Indian  Standard  given  at  serial  number  (2) 
of  the  list  of  standards  given  at  the  end  of  Part  7,  that  is,  IS  16416  :  2016 
‘Construction  project  management:  Project  formulation  and  appraisal  — 
Guidelines’. 

b)  Good  practice  [8-1(6)]  refers  to  the  Indian  Standard  given  at  serial  number 
(6)  of  the  list  of  standards  given  at  the  end  of  Section  1  of  Part  8,  that  is, 
IS  3362  :  1977  ‘Code  ofpractice  for  natural  ventilation  of  residential  buildings 
( first  revision)’ . 

c)  Good  practice  [8-3(  1 6)]  refers  to  the  Indian  Standard  given  at  serial  number 
(16)  of  the  list  of  standards  given  at  the  end  of  Section  3  of  Part  8,  that  is, 
IS  4831  :  1968  ‘Recommendation  on  units  and  symbols  for  refrigeration’. 

d)  Accepted  standard  [8-5A(6)]  refers  to  the  Indian  Standard  given  at  serial 
number  (6)  of  the  list  of  standards  given  at  the  end  of  Subsection  5A  of 
Part  8,  that  is,  IS  14665  (Part  3/Sec  1  and  2)  :  2000  ‘Electric  traction  lifts: 
Part  3  Safety  rules,  Section  1  Passenger  and  goods  lifts,  Section  2  Service 
lifts’. 

e)  Accepted  standards  [8-6(2)]  refers  to  the  Indian  Standards  given  at  serial 
number  (2)  of  the  list  of  standards  given  at  the  end  of  Section  6  of  Part  8, 
that  is,  IS  9537  (Part  3)  :  1983  ‘Specification  for  conduits  for  electrical 
installations:  Part  3  Rigid  plain  conduits  for  insulating  materials’  and 
IS  3419  :  1989  ‘Specification  for  fittings  for  rigid  non-metallic  conduits 
{second  revision)’ . 

f)  Accepted  standard  [9-1(1)]  refers  to  the  Indian  Standard  given  at  serial 
number  (1)  of  the  list  of  standards  given  at  the  end  of  Section  1  of  Part  9, 
that  is,  IS  10446  :  1983  ‘Glossary  of  terms  relating  to  water  supply  and 
sanitation’. 


(iv) 


INFORMATION  FOR  THE  USERS  ABOUT  AVAILABILITY  OF 
THE  CODE  IN  GROUPS 


For  the  convenience  of  the  users,  the  National  Building  Code  of  India  2016  is  available  as  a  comprehensive 
volume  as  well  as  in  the  following  five  groups,  each  incorporating  the  related  Parts/Sections  dealing  with  particular 
area  of  building  activity: 


Group  1 

For  Development/ 

PartO 

Integrated  Approach  —  Prerequisite  for  Applying  Provisions  of  the  Code 

Building  Planning 

Part  1 

Definitions 

and  Related 

Part  2 

Administration 

Aspects 

Part  3 

Development  Control  Rules  and  General  Building  Requirements 

Part  4 

Fire  and  Life  Safety 

Part  5 

Building  Materials 

Part  10 

Landscape  Development,  Signs  And  Outdoor  Display  Structures 

Section  1 

Landscape  Planning,  Design  and  Development 

Section  2 

Signs  and  Outdoor  Display  Structures 

Part  1 1 

Approach  to  Sustainability 

Group  2 

For  Structural 

PartO 

Integrated  Approach  —  Prerequisite  for  Applying  Provisions  of  the  Code 

Design  and  Related 

Part  6 

Structural  Design 

Aspects 

Section  1 

Loads,  Forces  and  Effects 

Section  2 

Soils  and  Foundations 

Section  3 

Timber  and  Bamboo 

3A  Timber 

3B  Bamboo 

Section  4 

Masonry 

Section  5 

Concrete 

5A  Plain  and  Reinforced  Concrete 

5B  Prestressed  Concrete 

Section  6 

Steel 

Section  7 

Prefabrication,  Systems  Building  and  Mixed/  Composite 
Construction 

7A  Prefabricated  Concrete 

7B  Systems  Building  and  Mixed/  Composite  Construction 

Section  8 

Glass  and  Glazing 

Part  1 1 

Approach  to  Sustainability 

Group  3 

For  Aspects 

PartO 

Integrated  Approach  —  Prerequisite  for  Applying  Provisions  of  the  Code 

Relating  to 

Part  7 

Construction  Management,  Practices  and  Safety 

Construction,  and 

Part  1 1 

Approach  to  Sustainability 

Asset/  Facility 

Part  12 

Asset  and  Facility  Management 

Management 

Group  4 

For  Aspects 

PartO 

Integrated  Approach  —  Prerequisite  for  Applying  Provisions  of  the  Code 

Relating  to  Building 

Part  8 

Building  Services 

Services 

Section  1 

Lighting  and  Natural  Ventilation 

Section  2 

Electrical  and  Allied  Installations 

Section  3 

Air  Conditioning,  Pleating  and  Mechanical  Ventilation 

Section  4 

Acoustics,  Sound  Insulation  and  Noise  Control 

Section  5 

Installation  of  Lifts,  Escalators  and  Moving  Walks 

5A  Lifts 

5B  Escalators  and  Moving  Walks 

Section  6 

Information  and  Communication  Enabled  Installations 

Part  11 

Approach  to  Sustainability 

Group  5 

For  Aspects 

PartO 

Integrated  Approach  —  Prerequisite  for  Applying  Provisions  of  the  Code 

Relating  to 

Part  9 

Plumbing  Services  (including  Solid  Waste  Management) 

Plumbing  Services 

Section  1 

Water  Supply 

and  Solid  Waste 

Section  2 

Drainage  and  Sanitation 

Management 

Section  3 

Solid  Waste  Management 

Section  4 

Gas  Supply 

Part  1 1 

Approach  to 

Sustainability 

The  information  contained  in  different  groups  will  serve  the  concerned  professionals  dealing  with  the  respective 
areas.  However,  it  is  advisable  that  professionals  essentially  dealing  with  any  of  the  above  groups  should  also 
refer  the  other  groups. 


(v) 


NATIONAL  BUILDING  CODE  OF  INDIA 

PART  7  CONSTRUCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


BUREAU  OF  INDIAN  STANDARDS 


CONTENTS 


FOREWORD  ...  3 

1  SCOPE  ...  7 

2  TERMINOLOGY  ...  7 

3  GENERAL  ...  7 

SECTION  1  CONSTRUCTION  MANAGEMENT 

4  CONSTRUCTION  PROJECT  MANAGEMENT  ...  8 

SECTION  2  CONSTRUCTION  PLANNING  AND  SITE  MANAGEMENT 

5  PLANNING  ASPECTS  ...  17 

SECTION  3  CONSTRUCTION  PRACTICES 

6  CONSTRUCTION  CONTROL  AND  PRACTICES  ...  19 

7  TEMPORARY  WORKS  ...  21 

8  STORAGE,  STACKING  AND  HANDLING  PRACTICES  ...23 

SECTION  4  SAFETY  IN  CONSTRUCTION 

9  SAFETY  IN  CONSTRUCTION  OF  ELEMENTS  OF  A  BUILDING  ...  34 

10  SAFETY  IN  DEMOLITION  OF  BUILDINGS  ...  52 

SECTION  5  REPAIRS,  RETROFITTING  AND  STRENGTHENING  OF  BUILDINGS 

11  MAINTENANCE  MANAGEMENT  ...  57 

12  PREVENTION  OF  CRACKS  ...  57 

1 3  REPAIRS  AND  SEISMIC  STRENGTHENING  OF  BUILDINGS  ...  58 

SECTION  6  HABITAT  AND  WELFARE  REQUIREMENTS  FOR  WORKERS 

14  HABITAT  AND  OTHER  WELFARE  REQUIREMENTS  FOR  CONSTRUCTION  ...  59 
WORKERS 

ANNEX  A  CHECK  LIST  FOR  STACKING  AND  STORAGE  OF  MATERIALS  ...  63 

LIST  OF  STANDARDS  ...  64 


2 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


National  Building  Code  Sectional  Committee,  CED  46 


FOREWORD 

This  Code  (Part  7)  covers  construction  project  management;  construction  planning,  site  management  and  building 
construction  practices;  storage,  stacking  and  handling  of  materials;  and  safety  of  personnel  during  construction 
operations  for  all  elements  of  a  building  and  demolition  of  buildings;  and  habitat  and  welfare  requirements  for 
workers.  It  also  covers  guidelines  relating  to  repairs,  retrofitting  and  strengthening  of  buildings. 

The  principles  enunciated  in  the  various  sections  of  this  Part  are  to  be  ultimately  utilized  and  implemented  in  the 
physical  construction  of  the  buildings  with  the  required  infrastructure.  This  would  require  sound  construction 
practices  and  efficient  management  thereof  in  order  to  ensure  that  the  implementation  of  the  project  is  carried  out 
within  the  estimated  cost  and  planned  period  to  the  required  quality  standards  and  in  a  safe  and  sustainable 
manner.  Workers  in  large  number,  both  skilled  and  unskilled,  are  engaged  in  the  innumerable  construction  works. 
Due  to  increased  tempo  of  such  a  building  activity  and  large  scale  mechanization,  hazards  of  accidents  could 
increase  considerably.  It  is,  therefore,  imperative  that  adequate  safety  rules  are  laid  down  for  every  phase  of 
construction  work.  It  is  also  important  to  give  due  cognizance  to  habitat  and  welfare  requirements  of  workers  at 
construction  site.  This  Part  also  deals  with  these  aspects. 

Planning  the  various  construction  operations  before  hand  and  making  adequate  arrangements  for  procurement 
and  storage  of  materials,  and  the  machinery  to  get  work  done  is  as  important  as  carrying  out  these  construction 
operations  in  accordance  with  good  practice.  Lack  of  planning  or  defective  planning  may  result  in  avoidable 
delay  in  the  completion  of  work  and  consequently  increased  hazards  from  the  point  of  view  of  fire,  health  and 
structural  soundness.  This  Part  covers  provisions  in  this  regard. 

A  construction  project  is  an  endeavour  undertaken  by  a  project  team  on  behalf  of  owner/client  to  create  a  built 
facility  suited  to  the  defined  functional  objectives.  From  inception  to  commissioning,  the  project  goes  through 
various  distinct  stages  leading  to  progressive  achievement  of  project  objectives.  Each  stage  involves  specific 
inputs,  processes  (both  technical  and  managerial)  and  deliverables.  Typically,  the  life  cycle  of  a  project  from 
commencement  to  completion  involves  the  following  stages: 

a)  Project  formulation  and  appraisal  —  Inception,  feasibility  and  strategic  planning; 

b)  Project  development  —  Project  brief  development,  planning  and  design,  finalization  of  proposals, 
procurement  strategy,  construction  documentation  including  tender  drawings,  working  drawings, 
specifications,  cost  estimates,  bills  of  quantities,  procurement  documents; 

c)  Planning  for  construction  —  Sequencing  of  project  components,  planning  tools,  resource  planning  and 
time  cost  trade  off; 

d)  Tender  action  —  Open  competitive  bidding/pre-qualification  of  agencies,  issue  of  tender  documents, 
evaluation  of  bids,  negotiation  if  required  and  award  of  work; 

e)  Construction  —  Execution,  monitoring,  control,  work  acceptance;  and 

f)  Commissioning  and  handing  over  —  Contractual  closeout,  financial  closeout,  defect  liability 
commencement,  facility  handing  over. 

The  distinct  features  of  a  construction  project  include  the  temporary  nature  of  the  organizations  involved,  the 
evolutionary  process  of  project  deliverables  during  project  development  stages  and  the  unique  output  of  the  built 
facility.  As  a  result  of  these  features,  unless  there  is  efficient  and  effective  project  management,  a  construction 
project  is  faced  with  challenges  of  uncertainties  leading  to  time  over-runs,  cost  over-runs,  changes  in  project 
parameters,  loss  of  quality  and  inability  to  meet  the  functional  objectives.  While  technical  soundness  of  a  proposal 
is  an  important  aspect  of  a  construction  project,  the  management  aspects,  which  involve  techno-legal,  financial 
and  other  issues,  have  also  a  significant  role  in  the  success  of  a  project.  Therefore,  management  functions  and 
technical  processes  in  a  construction  project  need  to  be  integrated  towards  achieving  project  objectives.  Top 
management  commitment  plays  an  important  role  in  harmoniously  achieving  these  project  objectives.  In  some  of 
the  public  sector  projects,  it  may  be  necessary  to  share  relevant  information  with  public  at  large  through  appropriate 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


3 


means.  The  overall  management  of  a  building  construction  project  is  very  important  to  ensure  that  the  objectives 
of  such  a  project  are  achieved  through  scope  management,  procurement  management,  time  management,  cost 
management,  quality  management,  risk  management,  communication  management,  human  resources  management, 
safety,  health  and  environment  management  and  integration  management.  This  Part,  therefore,  gives  guidelines 
on  these  areas. 

The  first  version  of  this  Part  was  formulated  in  1970,  which  was  subsequently  revised  in  1983  and  2005.  In  the 
first  revision,  information  regarding  handling  operations  that  is  unloading,  stacking,  lifting,  loading  and  conveying 
of  building  materials,  was  also  given  along  with  the  storage  practices.  Additional  information  regarding  the  use  of 
ladders;  safety  requirements  for  floor  and  wall  openings,  railings  and  toe  boards;  piling  and  other  deep  foundations; 
constructions  involving  use  of  hot  bituminous  materials;  and  erection  of  structural  steel  work  and  concrete  framed 
structures,  etc,  were  included. 

In  the  second  revision,  the  Section  1  ‘Construction  Practices’  of  this  Part,  had  been  revamped  to  include  the 
planning  and  management  aspects.  Further,  provisions  on  construction  using  bamboo  were  also  incorporated.  The 
other  important  modifications  incorporated  in  the  second  revision  included  comprehensive  updating  of  the 
provisions  with  regard  to  stacking  and  storage  of  building  materials  and  components,  which  were  comprehensively 
covered  in  line  with  the  revised  IS  4082  :  1996  ‘Recommendations  on  stacking  and  storage  of  construction 
materials  and  components  at  site  ( second  revision)' ;  addition  of  provisions  of  safety  requirements  of  hoists/lifts 
for  worker  during  construction;  incorporation  of  aspects  like  preventive  measures  such  as  falling  material  hazards 
prevention,  fall  prevention,  disposal  of  debris,  fire  protection,  etc,  with  regard  to  safety  at  work  site;  addition  of 
provisions  regarding  safety  management  at  work  sites;  addition  of  a  new  section  on  ‘Maintenance  management, 
repairs,  retrofitting  and  strengthening  of  buildings’,  covering  aspects  like  maintenance  management,  prevention 
of  cracks,  and  repairs  and  seismic  strengthening  of  buildings;  and  updating  of  safety  provisions  with  respect  to 
demolition  of  buildings. 

As  a  result  of  experience  gained  in  implementation  of  2005  version  of  this  Part  and  feedback  received  as  well  as 
in  view  of  formulation  of  new  standards  in  the  field  of  construction  project  management  and  construction  practices 
and  revision  of  some  existing  standards,  including  those  on  safety,  a  need  to  revise  this  Part  was  felt.  This  revision 
has,  therefore,  been  prepared  to  take  care  of  these  aspects.  This  Part  has  been  divided  into  six  sections  as  follows, 
under  which  all  technical  provisions  relating  to  their  subject  areas,  have  been  given: 

Section  1  Construction  Management 

Section  2  Construction  Planning  and  Site  Management 

Section  3  Construction  Practices 

Section  4  Safety  in  Construction 

Section  5  Repairs,  Retrofitting  and  Strengthening  of  Buildings 

Section  6  Habitat  and  Welfare  Requirements  for  Workers 

The  significant  changes  incorporated  in  this  revision  include: 

a)  This  Part  has  been  divided  into  six  Sections  under  which  the  provisions  have  been  rearranged  in  a  logical 
sequence; 

b)  Provisions  on  construction  project  management  have  been  detailed  which  also  now  includes  project 
formulation  and  appraisal. 

c)  Safety  provisions  with  respect  to  scaffolding,  piling  and  other  deep  foundations,  blasting  and  related 
drilling  operations,  and  construction  involving  use  of  hot  bituminous  materials  have  been  updated; 

d)  A  new  clause  on  habitat  and  other  welfare  requirements  for  construction  workers  has  been  introduced; 

e)  A  new  clause  on  urban/city  roads  planning  and  construction,  has  been  added; 

f)  A  new  clause  on  temporary  works  has  been  included; 

g)  Provisions  on  construction  using  bamboo  has  been  shifted  to  Part  6  ‘Structural  Design,  Section  3B 
Bamboo,  and  a  reference  to  the  same  has  been  given  in  this  Part; 

h)  Provisions  on  maintenance  management  has  been  shifted  to  Part  12  ‘Asset  and  Facility  Management’  of 
the  Code  and  a  reference  to  the  same  has  been  given  in  this  Part;  and 

j)  References  to  all  the  concerned  Indian  Standards  have  been  updated. 

Users  are  encouraged  to  employ  suitable  construction  management  software  as  an  aid  to  implement  provisions  of 


4 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


this  Code.  The  guidelines  may  be  applicable  in  general  to  all  construction  projects.  However,  for  smaller  projects, 
the  applicability  of  various  provisions  may  be  decided  appropriately  by  the  parties  concerned. 

Provisions  on  sustainable  building  construction  practices  are  covered  in  Part  11  ‘Approach  to  Sustainability’  of 
the  Code. 


The  information  contained  in  this  Part  is  largely  based  on  the  following  Indian  Standards  and  Special  Publications: 


Safety  code  for  scaffolds  and  ladders: 

Scaffolds 
Ladders 

Code  of  practice  for  excavation  work  (first  revision) 

Recommendations  on  stacking  and  storage  of  construction  materials  and  components  at 
site  ( second  revision) 

Safety  code  for  demolition  of  buildings  ( second  revision) 

Safety  requirements  for  floor  and  wall  openings,  railing  and  toe  boards  (first  revision) 
Code  of  safety  for  piling  and  other  deep  foundations  (first  revision) 

Safety  code  for  construction  involving  use  of  hot  bituminous  materials  (first  revision) 
Safety  code  for  erection  of  structural  steel  work 
Safety  code  for  handling  and  storage  of  building  materials 
Safety  code  for  erection  of  concrete  framed  structures 
Safety  code  for  protective  barrier  in  and  around  buildings 
Recommendations  for  preventive  measures  against  hazards  at  work  places: 

Falling  material  hazards  prevention 
Fall  prevention 
Disposal  of  debris 
Timber  structures 
Fire  protection 

Code  of  practice  for  safety  during  additional  construction  and  alteration  to  existing 
buildings 

:  Guidelines  for  construction  project  management:  Part  1  General 

Guidelines  for  habitat  and  welfare  requirements  for  construction  workers 
A  reference  to  SP  62  :  1992  ‘Handbook  on  building  construction  practices  (excluding  electrical  works)’  and 
SP  70  :  2001  ‘Handbook  on  construction  safety  practices’,  may  also  be  made. 

All  standards,  whether  given  herein  above  or  cross-referred  to  in  the  main  text  of  this  Part,  are  subject  to  revision. 
The  parties  to  agreement  based  on  this  Part  are  encouraged  to  investigate  the  possibility  of  applying  the  most 
recent  editions  of  the  standards. 


IS  3696 

(Part  1 ) 

:  1987 

(Part  2) 

:  1991 

IS  3764  : 

1992 

IS  4082  : 

1996 

IS  4130  : 

1991 

IS  4912  : 

1978 

IS  5121  : 

2013 

IS  5916  : 

2013 

IS  7205  : 

1974 

IS  7969  : 

1975 

IS  8989  : 

1978 

IS  13415 

:  1992 

IS  13416 

(Part  1) 

:  1992 

(Part  2) 

:  1992 

(Part  3) 

:  1994 

(Part  4) 

:  1994 

(Part  5) 

:  1994 

IS  13430 

:  1992 

IS  15883  (Part  1) 

2009 

IS  16601 

:  2016 

For  the  purpose  of  deciding  whether  a  particular  requirement  of  this  Code  is  complied  with,  the  final  value, 
observed  or  calculated,  expressing  the  result  of  a  test  or  analysis,  shall  be  rounded  off  in  accordance  with  IS  2  :  1 960 
‘Rules  for  rounding  off  numerical  values  (revised)’ .  The  number  of  significant  places  retained  in  the  rounded  off 
value  should  be  the  same  as  that  of  the  specified  value  in  this  Part. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


5 


NATIONAL  BUILDING  CODE  OF  INDIA 

PART  7  CONSTRUCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


1  SCOPE 

1.1  This  Code  (Part  7)  covers  construction  project 
management;  construction  planning,  site  management 
and  building  construction  practices;  storage,  stacking 
and  handling  of  materials;  and  safety  of  personnel 
during  construction  operations  for  all  elements  of  a 
building  and  demolition  of  buildings;  and  habitat  and 
welfare  requirements  for  workers.  It  also  covers 
guidelines  relating  to  repairs,  retrofitting  and 
strengthening  of  buildings. 

1.2  The  provisions  in  respect  of  sustainable  building 
construction  practices  are  covered  in  Part  1 1  ‘Approach 
to  Sustainability’  of  the  Code  which  shall  be  used  in 
conjunction  with  this  Part. 

1.3  Provisions  relating  to  maintenance  management  are 
covered  in  Part  12  ‘Asset  and  Facility  Management’  of 
the  Code  which  has  been  referred  to  in  this  Part. 

2  TERMINOLOGY 

For  the  purpose  of  this  Part,  the  following  definitions 
shall  apply,  and  for  other  terms  those  given  in  the 
accepted  standards  [7(1)]  shall  apply. 

2.1  Authority  Having  Jurisdiction 

The  authority  which  has  been  created  by  a  statute  and 
which  for  the  purpose  of  administering  the  Code/Part, 
may  authorize  a  committee  or  an  official  to  act  on  its 
behalf;  hereinafter  called  the  ‘Authority’. 

2.2  Definitions  Relating  to  Safety  in  Construction 

2.2.1  Construction  Equipment  —  All  equipment, 
machinery,  tools  and  temporary  retaining  structures  and 
working  platforms,  that  is,  tools,  derricks,  staging, 
scaffolds,  runways,  ladders  and  all  material,  handling 
equipment  including  safety  devices. 

2.2.2  Floor  Hole  —  An  opening  measuring  less  than 
300  mm  but  more  than  25  mm  in  its  least  dimension,  in 
any  floor,  platform,  pavement,  or  yard,  through  which 
materials  but  not  persons  may  fall;  such  as,  a  belt  hole, 
pipe  opening  or  slot  opening. 

2.2.3  Floor  Opening — An  opening  measuring  300  mm 
or  more  in  its  least  dimension,  in  any  floor,  platform, 
pavement  or  yard  through  which  person  may  fall;  such 
as  hatch  way,  stair  or  ladder  opening,  pit  or  large 
manhole. 

2.2.4  Guard  Railing — A  barrier  erected  along  exposed 
edges  of  an  open  side  floor  opening,  wall  opening, 


ramp,  platform,  or  catwalk  or  balcony,  etc,  to  prevent 
fall  of  persons. 

2.2.5  Materials  Handling  Hoists  —  A  platform,  bucket 
or  similar  enclosure  exclusively  meant  for  the  lifting 
or  lowering  of  construction  material,  the  hoists  being 
operated  from  a  point  outside  the  conveyance. 

2.2.6  Pile  Rig  —  The  complete  pile  driving  equipment 
comprising  piling  frame,  leader,  hammer,  extractor 
winch  and  power  unit.  Complete  pile  driving  rig  may 
be  mounted  on  rafts  or  pontoon  or  rails.  Pile  rig  may 
also  be  a  mobile  unit  mounted  on  trailers  or  trucks,  or 
a  special  full  revolving  rig  for  raking  piles. 

2.2.7  Platform — A  working  space  for  persons,  elevated 
above  the  surrounding  floor  or  ground,  such  as  balcony 
or  platform  for  the  operation  of  machinery  and 
equipment. 

2.2.8  Scaffold  —  A  temporary  structure  consisting  of 
standards,  putlogs,  ledgers,  generally  of  bamboo, 
Bailies,  timber  or  metal  to  provide  a  working  platform 
for  workers  and  materials  in  the  course  of  construction, 
maintenance,  repairs  and  demolition,  and  also  to 
support  or  allow  hoisting  and  lowering  of  workers,  their 
tools  and  materials. 

2.2.9  Toe  Board  —  A  vertical  barrier  erected  along 
exposed  edge  of  a  floor  opening,  wall  opening, 
platform,  catwalk  or  ramp  to  prevent  fall  of  materials 
or  persons. 

2.2.10  Wall  Hole  —  An  opening  in  any  wall  or  partition 
having  height  of  less  than  750  mm  but  more  than  25  mm 
and  width  unrestricted. 

2.2.11  Wall  Opening  —  An  opening  in  any  wall  or 
partition  having  both  height  of  at  least  750  mm  and 
width  of  at  least  450  mm. 

3  GENERAL 

3.1  A  general  overview  of  construction  project 
management  and  information  regarding  the  applicable 
tools  and  techniques  are  covered  in  Section  1 
‘Construction  Management’  of  this  Part,  which  also 
demarcates  various  stages  of  a  construction  project  and 
activities  thereunder.  Section  1  gives  brief  guidelines 
on  project  formulation  and  appraisal,  and  various 
construction  project  management  functions;  and  for 
detailed  guidelines  on  each  of  these,  gives  reference  to 
the  available  good  practices. 

Construction  planning  and  site  management,  plays  an 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


7 


important  role  in  smooth  progress  of  a  building 
construction  activity  and  are  covered  in  Section  2 
‘Construction  Planning  and  Site  Management’.  The 
knowledge  of  actual  technical  provisions  in  regard  to 
practices  relating  to  various  building  components 
starting  from  sub-structure  to  super-structure,  play  a 
key  role  in  achieving  the  quality  of  building 
construction.  Also,  temporary  enabling  works;  proper 
stacking  and  storage  of  materials;  and  well  planned 
handling  operations,  have  important  role  in  proper,  safe 
and  smooth  progress  in  construction  work  at  site.  The 
provisions  in  respect  of  these  are  covered  in  Section  3 
‘Construction  Practices’. 

The  objectives  of  sound  construction  of  buildings 
having  requisite  quality,  durability  and  finish  has  to  be 
duly  dovetailed  with  the  goals  of  safety  whether  during 
construction  of  a  new  building  or  addition/alteration 
to  an  existing  building  part  thereof  or  during  demolition 
of  an  existing  building.  Section  4  ‘Safety  in 
Construction’  covers  provisions  to  these  effects. 

Section  5  ‘Repairs,  Retrofitting  and  Strengthening  of 
Buildings’  covers  repair,  retrofitting  and  strengthening 
of  existing  buildings  and  Section  6  ‘Habitat  and  Welfare 
Requirements  for  Workers’  deals  with  habitat  and  other 
welfare  requirements  for  construction  workers  at  site. 

3.2  The  objective  of  universal  design  and  accessibility 
is  to  ensure  that  all  users,  including  those  with 
disabilities  and  elderly  people  are  able  to  access  all  the 
facilities  within  the  built  environment  including  in  the 
public  buildings,  on  an  equal  basis.  Requirements  for 
accessibility  in  built  environment  for  the  elderly  and 
for  persons  with  disabilities  as  given  in  13  of  Part  3 
‘Development  Control  Rules  and  General  Building 
Requirements’  of  the  Code  shall  be  complied  with  at 
all  stages  of  the  construction  project. 

SECTION  1  CONSTRUCTION 
MANAGEMENT 

4  CONSTRUCTION  PROJECT  MANAGEMENT 
4.1  General 

4. 1 . 1 A  proj  ect  is  generally  a  non-recurring  task  having 
a  definable  beginning  and  end,  with  a  definite  mission 
and  has  a  set  of  objectives  and  achievements.  Project 
management  is  application  of  knowledge,  skills,  tools 
and  techniques  to  achieve  the  objectives  of  a  defined 
project  with  the  aim  to  ensure  that  a  project  is  completed 
within  the  scheduled  time,  authorized  cost  and  to  the 
requirement  of  quality  standards.  Construction  project 
management  refers  to  such  project  management  when 
applied  to  construction  of  built  facility.  Project 
objectives  depend  on  the  requirements  of  the  built 
facility.  From  the  point  of  view  of  construction  project 
management,  project  objectives  may  be  defined  in 


terms  of  scope,  time,  cost  and  quality.  This  may  usually 
take  place  in  project  appraisal  stage  and  shall  be  done 
in  accordance  with  the  good  practice  [7(2)]. 
Information  and  guidelines  given  under  4.1.2  to  4.1.6 
shall  be  appropriately  utilized  under  different  stages 
of  construction  project. 

4.1.2  Stakeholder 

Stakeholder  is  a  person,  group  of  persons  or 
organizations  who  are  actively  involved  in  the  project 
or  those  who  have  an  interest  in  the  success  of  a  project 
and  its  environment.  Generally  in  a  construction  project, 
besides  the  owner/client,  the  project  manager, 
consultants,  construction  agencies  and  the  users  are  the 
stakeholders.  In  addition,  depending  on  the  nature  of 
the  project,  there  may  be  other  stakeholders  such  as 
financer,  government  and  public  at  large. 

4.1.3  Construction  Project  Life  Cycle 

Construction  project  life  cycle  consists  of  project 
formulation  and  appraisal,  project  development, 
planning  for  construction,  tender  action,  construction, 
and  commissioning  and  handing  over,  as  main  stages. 
These  stages  involve  defined  decisions,  deliverables 
and  completion  of  mile-stones  for  control  of  project, 
ensuring  that  the  adverse  impact  of  uncertainties  is 
overcome  at  each  stage  in  the  progress.  Accordingly, 
the  responsibilities  of  project  team  should  be  defined 
and  measured  for  acceptance,  and  liabilities  determined 
objectively. 

Project  objectives,  drawn  out  of  feasibility  established 
in  the  appraisal  stage,  are  achieved  progressively 
through  each  of  the  project  life  cycle  stages.  The  stage- 
wise  break-up  of  project  objectives,  tasks,  compliance 
and  authorization  to  proceed  further  in  the  next  stage 
should  be  structured  comprehensively  through  various 
stages  of  life  cycle.  Each  stage  of  construction  project 
life  cycle  may  be  considered  as  a  subproject,  thus 
making  overall  complexities  of  a  project  more 
manageable. 

A  typical  construction  project  life  cycle  is  given  in 
Fig.  1. 

4.1.4  Construction  Project  Delivery  Models 

Project  delivery  model  determines  the  manner  in  which 
the  project  is  planned,  designed,  executed  and  contract 
administration  carried  out.  It  also  determines  the 
contractual  relationships  between  the  owner/client, 
design  consultants  and  construction  agency.  The 
delivery  model  shall  define  the  span  of  control  and  role 
and  responsibilities  of  each  of  the  above  parties.  The 
main  types  of  project  delivery  models  that  are  in  vogue 
in  construction  projects  are:  (a)  Traditional  design-bid- 
build,  (b)  Design-build  with  variants,  (c)  Turn-key  and 
(d)  Build,  operate  and  transfer  and  its  variants.  Each 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


TIME  - - 

Fig.  1  Typical  Construction  Project  Life  Cycle 


of  the  delivery  models  can  adopt  different  types  of 
contracts  depending  upon  the  suitability  of  the  contract 
type  in  relation  to  the  nature  and  type  of  projects, 
project  objectives  and  other  project  specific 
considerations. 

4.1.5  Construction  Methodologies  and  Techniques 

Suitable  construction  methodologies  and  techniques, 
such  as,  conventional,  prefabrication,  systems  building 
approach,  mixed/composite  construction,  mechanization 
in  construction  and  other  innovative  technologies,  shall 
be  defined  considering  design  principles  adopted  and 
also  considering  the  project  objectives  in  terms  of  factors, 
like,  scope,  time,  cost  and  quality  requirements.  Method 
statement  may  be  made  for  all  critical  items  of  work. 

4.1.6  Organizational  Structures 

Organizational  structure  depends  on  the  project  delivery 
model.  As  an  example,  a  typical  organization  chart  for 
Design-Bid-Build  model  is  given  in  Fig.  2. 

4. 1.6.1  Construction  project  management 
organizational  teams 

For  any  given  project  delivery  model,  an  appropriate 
organizational  structure  shall  be  selected  so  as  to  facilitate 
constitution  of  teams  across  various  agencies  involved. 
Such  teams  are  fundamental  functional  units  generally 
specific  to  each  of  the  life  cycle  stages  of  a  project. 

Flealth,  Safety  and  Environment  (HSE)  and  quality  set 
up  shall  directly  report  to  the  Project  Manager. 

4.2  Stages  of  a  Construction  Project 

4.2.1  Typically  a  construction  project  (whether  small 
or  large)  may  be  considered  to  involve  the  following 
distinct  broad  stages: 


a)  Project  formulation  and  appraisal  stage: 

1)  Inception, 

2)  Feasibility,  and 

3)  Strategic  planning. 

b)  Pre-construction  stage: 

1)  Project  development, 

2)  Planning  for  construction,  and 

3)  Tender  action. 

c)  Construction  stage,  and 

d)  Commissioning  and  handing  over  stage. 

4.2.2  Project  Formulation  and  Appraisal  Stage 

For  successful  management  of  construction  projects, 
the  earlier  stages  when  the  construction  project  is 
conceived,  formulated  and  its  feasibility  assessed, 
leading  to  decision  to  implement  the  project,  are  equally 
important.  The  guidelines  given  in  the  good  practice 
[7(2)]  should  be  employed  during  project  formulation 
and  appraisal  stage  of  a  construction  project. 

NOTE  —  This  stage  of  a  construction  project  is  basically  the 
preliminary  stage  covering  activities  up  to  the  stage  of 
preparation  of  proposals  for  obtaining  approval  for 
implementing  the  project  including  financial  approval  and 
includes  inception,  pre-feasibility,  feasibility,  related  project 
strategic  planning  and  viability  assessment  and  review  prior  to 
approval  of  project. 

For  all  other  above  stages,  the  relevant  construction 
management  function  guidelines  given  in  4.3  should 
be  employed  for  achieving  the  intended  objectives. 

4.2.3  Pre-Construction 
4.2.3. 1  Project  development 
This  shall  involve  the  following: 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


9 


NOTE  —  ‘Consultants’  may  cover  in-house  teams  or  outside  consultants. 

Fig.  2  Typical  Organization  Structure  for  Design-Bid-Build  Model 


a)  Formalization  of  design  brief; 

b)  Site  survey  and  soil  investigation; 

c)  Fiazard  risk  vulnerability  analysis; 

d)  Alternative  concept  designs  with  costing  and 
finalization; 

e)  Preliminary  designs  and  drawings; 

f)  Development  of  design  of  each  discipline  and 
their  integration; 

g)  Obtaining  statutory  approvals; 

h)  Selection  of  construction  methodology; 

j)  Preliminary  cost  estimates; 

k)  Detailed  planning  and  design  of  each 
discipline; 

m)  Construction  working  drawings  and  related 
specifications  with  integration  of  engineering 
inputs  of  all  concerned  disciplines; 

n)  Detailed  cost  estimates; 

p)  Detailed  specifications  and  bills  of  quantities; 
and 

q)  Tender  documents. 

Peer  review/proof  checking  of  the  drawings/designs/ 
estimates  shall  be  done  in  case  of  important  projects, 
depending  upon  their  complexity  and  sensitivity. 
Environment  impact  analysis  and  social  impact  analysis 
shall  be  done  in  applicable  cases. 

4.2.3.2  Planning  for  construction 

The  following  aspects  shall  be  considered: 

a)  Sequencing  of  project  components, 

b)  Planning  tools: 

1)  Work  breakdown  structures  (WBS), 


2)  Bar  charts,  and 

3)  Network  techniques  and  scheduling. 

c)  Resource  planning,  and 

d)  Time  cost  trade  off. 

4.2.3.2.1  Sequencing  of  project  components 

Methodology  of  construction  shall  be  detailed  before 
the  start  of  the  project.  Sequencing  of  project 
components  shall  be  done  on  the  basis  of  methodology 
adopted  and  availability  of  resources.  This  shall  be 
reviewed  during  the  progress  of  the  project  and  revised, 
if  necessary. 

4.2.3.2.2  Planning  tools 

The  planning  tools  described  below  may  be  employed 
for  effective  management  of  a  construction  project: 

a)  Work  breakdown  structure  (WBS)  —  The 
WBS  shall  identify  the  total  scope  of  works 
involved  in  the  project  and  shall  form  the  basis 
for  the  development  of  detailed  project 
schedule.  Through  WBS,  the  project  shall  be 
subdivided  into  major  subdivisions  (work 
packages)  and  each  major  subdivision  shall 
be  further  subdivided  into  additional  levels  as 
required  up  to  the  level  of  activities  that  could 
form  the  basis  for  monitoring  and  control  of 
project  performance  in  terms  of  time,  cost  and 
quality  parameters.  WBS  shall  provide  activity 
listing  with  associated  cost  account  codes  for 
the  preparation  of  project  schedule  either  by 
bar  charts  or  by  network  diagramming 
methods. 

b)  Bar  chart  —  Bar  chart  is  the  simplest  form  of 


10 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


project  scheduling  and  used  for  small  and 
complex  projects  and  in  preliminary  planning 
and  tender-stages  of  major  projects.  A  typical 
bar  chart  form  of  project  schedule  depicts  the 
various  activities  on  a  calendar  time  scale  in 
the  form  of  bars  in  their  relative  positions  with 
start  and  finish  dates  and  length  of  bar 
indicating  probable  activity  duration.  Linked 
bars  represent  the  interdependencies  between 
the  activities.  Bar  chart  type  of  schedule  shall 
be  used  to  comprehend,  summarize  and 
display  the  results  of  complex  project  network 
analysis  and  further  monitoring  and 
controlling  process. 

c)  Network  techniques  and  scheduling 

1)  Network  diagramming  methods  — 
Network  based  project  schedule  shall  be 
used  for  major  and  complex  projects.  In 
this  method,  the  network  of  project 
activities  identified  through  WBS  is 
developed  incorporating  their  logical 
relationships  and  interdependencies.  The 
two  available  approaches  for  network 
diagramming  techniques  are  arrow 
diagramming  method  (ADM)  and 
precedence  diagramming  method  (PDM). 

2)  Network  analysis  and  scheduling  —  The 
project  network  incorporating  the  activity 
durations  and  logical  relationships  shall 
be  analyzed  with  forward  and  backward 
pass  schedule  calculations  to  establish 
early  and  late  start  and  finish  time  of 
activities  with  their  available  floats, 
critical  activities,  critical  path  and  overall 
project  duration.  The  project  schedule  is 
prepared  in  terms  of  calendar  dates  of 
start  and  finish  of  activities  with  available 
floats.  The  network  schedule  shall  also 
be  presented  in  the  form  of  linked  bar 
chart  or  in  tabular  format. 

For  details  on  network  preparation  and 
analysis,  reference  shall  be  made  to  good 
practices  [7(3)].  Network  schedule  shall  be 
prepared  for  all  disciplines  and  they  shall  be 
integrated  into  a  master  control  schedule. 

4.2.3.2.3  Resource  planning 

This  shall  involve  the  following: 

a)  Resource  allocation  —  The  feasibility  of  the 
network  shall  be  checked  with  respect  to 
manpower,  equipment,  materials,  other 
resources  required  at  the  site. 

b)  Resource  levelling  —  It  shall  be  done  by  re¬ 
allocating  the  slack  resources  from  non- 
critical  path  to  critical  path  activity  in  order 


to  obtain  a  reduction  of  time  or  by  shifting 
the  activities  within  the  floats  available  with 
them,  to  obtain  optimum  uniform  resource 
requirements. 

c)  Resource  schedule  —  Schedule  of  following 
resource  requirements  with  respect  to  time 
shall  be  prepared  on  the  basis  of  network 
developed  and  kept  in  the  database  for  project 
control  purposes: 

1)  Technology, 

2)  Manpower: 

i)  Technical  staff, 

ii)  Skilled  labour, 

iii)  Unskilled  labour, 

3)  Machinery, 

4)  Materials,  and 

5)  Cash  flow. 

Resource  schedule  shall  be  prepared  separately  for 
client,  consultant  and  construction  agency. 

4.2.3.2.4  Time  cost  trade  off 

Time  cost  trade  off  analysis  shall  be  done  to  obtain  a 
minimum  total  cost  of  the  project  within  the  specified 
time.  This  shall  be  done  taking  into  consideration  direct 
cost  and  indirect  cost  of  the  project. 

4.2.3.3  Tender  action 

4.2.3.3.1  Preparation  of  tender  documents 

The  bill  of  quantities,  specifications,  drawings  and 
conditions  of  contract  should  be  prepared  on  the  basis 
of  design  and  details  finalized  in  project  proposal 
development  stage  (see  4.2.3. 1)  keeping  in  view  the 
construction  project  delivery  model  selected.  The 
format,  terminologies  and  terms  and  conditions  should 
be  as  per  the  standard  engineering  practices.  In  case  of 
any  special  item  or  condition,  the  same  shall  be 
described  clearly  to  avoid  any  ambiguity. 

4.2.3.3.2  Selection  of  construction  agency 
Selection  of  construction  agency  shall  be  done  by  either: 

a)  Open  competitive  bidding  —  In  this  case, 
tender  notice  should  be  publicized  adequately 
to  obtain  competitive  tenders  from  competent 
agencies  for  the  project;  or 

NOTE  —  Electronic  tendering  could  also  be  considered. 

b)  Limited  competitive  bidding  —  In  large, 
specialized  and  important  works, 
prequalification  of  contractors  shall  be  done 
considering  their  financial  capability,  bid 
capacity,  experience  of  similar  type  of  works, 
past  performance,  technical  staff,  and  plants 
and  machinery  available. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


11 


4.2.3.3.3  Bid  evaluation,  negotiation  and  award  of 
work 

After  due  evaluation  and  negotiation  with  the  bidders, 
if  required,  the  work  shall  be  awarded  to  the 
construction  agency  based  on  competitive  technical  and 
financial  bids. 

4.2.4  Construction 

This  is  one  of  the  most  important  stages  of  construction 
management  where  pre-construction  stage  outputs  are 
realized  into  physical  tangible  form  within  the 
constraints  of  time  and  cost.  The  intent  or  need  for 
functional  and  physical  characteristics,  defined  in  the 
pre-construction  stage  outputs  through  specifications, 
drawings  and  consolidated  project  brief  is  realized 
through  various  construction  project  management 
functions  described  in  4.3  and  particularly  through 
procurement  management,  time  management,  cost 
management,  quality  management  and  health,  safety 
and  environment  management. 

4.2.5  Commissioning  and  Handing  Over 

After  all  construction  activities  of  the  project  are 
complete  as  per  specifications  and  designs,  project 
commissioning  and  handing  over  stage  follows.  It  shall 
need  the  compliance  of  the  following: 

a)  Clearing  of  site, 

b)  Removal  of  all  defects  at  the  time  of 
completion  and  during  defect  liability  period, 

c)  Preparation  of  list  of  inventories, 

d)  Certification  and  settlement  of  construction 
agency’s  final  bills  for  payment, 

e)  Obtaining  completion  certificate  from  local 
government  bodies/departments, 

f)  Preparation  of  maintenance  manual, 

g)  Performance  compliance  verification  of  built 
facility, 

h)  Handing  over  all  other  required  documents, 
including  guarantees,  to  the  client/owner, 

j)  Restoration  of  surroundings,  and 

k)  Preparation  and  handing  over  all  as-built 
drawings. 

4.3  Construction  Project  Management  Functions 

Construction  project  management  consists  of  number 
of  processes  and  these  can  be  grouped  under  the 
following  management  functions: 

a)  Scope  management, 

b)  Procurement  management, 

c)  Time  management, 

d)  Cost  management, 

e)  Quality  management, 


f)  Risk  management, 

g)  Communication  management, 

h)  Human  resources  management, 

j)  Health  and  safety  management, 

k)  Sustainability  management, 

m)  Integration  management,  and 

n)  Other  management  processes. 

The  project  management  functions  briefly  described 
below  may  be  employed  for  effective  management  of 
construction  project  during  its  different  stages  as 
applicable.  Some  of  the  processes  may,  however, 
overlap  more  than  one  function. 

4.3.1  Scope  Management 

It  should  be  ensured  that  project  concept,  details  and 
functions  which  are  established  and  recorded  during 
the  finalization  stage,  remain  same  except  minor 
changes  and/or  authorized  variations.  Scope 
management  includes  the  processes  of  scope  planning, 
scope  definition,  scope  verification,  scope  monitoring, 
and  change  control. 

Scope  planning,  scope  definition  and  scope  verification 
are  associated  with  the  preconstruction  phase  of  the 
project.  Scope  monitoring  and  change  control  are 
critical  to  the  construction/installation  stage  in  order 
to  control  time  and  cost  over-runs.  The  work  break 
down  structure  of  the  project  shall  be  the  basic  tool  for 
defining  the  scope  baseline.  Scope  control  should  aim 
to  identify  factors  influencing  scope  change,  determine 
the  impact  of  scope  changes  and  establish  the  system 
for  scope  change  approval  and  revision  of  scope 
baseline.  Accordingly,  a  detailed  scope  management 
plan  should  be  drawn  to  lay  down  all  the  necessary 
practices  including  technical  and  organizational 
interfaces. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(4)]. 

4.3.2  Procurement  Management 

Procurement  management  includes  processes  for 
purchase  of  materials,  equipment,  products,  soliciting 
services  of  consultants  and  engaging  agencies  for 
execution  of  works  under  a  contract.  Project 
procurement  processes,  which  depend  on  type  of 
project  delivery  model  include  identification  of 
procurement  needs,  preparation  for  procurement, 
soliciting  proposals,  selection  of  suppliers/consultants/ 
works  contractors,  administering  of  contract,  contract 
management  and  closure  of  contract.  Project  manager 
is  charged  with  the  responsibility  to  help  structure  and 
develop  contract  to  suit  the  specific  needs  of  the  project. 
As  contract,  which  is  an  output  of  project  procurement 
management  processes,  is  a  legal  document,  the 
procurement  processes  should  follow  detailed 


12 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


procedures  with  adequate  review  and  stakeholder 
appraisal  opportunities. 

One  of  the  fundamental  issues  in  construction  projects, 
managed  through  project  managers,  is  to  determine 
what  needs  may  be  met  by  procuring  products,  services 
and  works  from  external  agencies  and  what  should  be 
accomplished  by  the  project  team.  This  decision  is  best 
arrived  at  the  earlier  stages  of  the  project  (so  that  the 
opportunities  of  procurement  initiation  at  earlier  stages 
is  not  lost)  and  reviewed  at  each  of  the  subsequent  life 
cycle  stages  of  the  project.  Such  decisions  should  draw 
inputs  from  the  time,  cost,  quality  and  scope 
management  processes.  Various  procurement  routes 
should  be  analysed  on  their  suitability  to  both  time  and 
cost  criteria  of  project.  As  a  strategy  for  procurement, 
a  project  procurement  management  plan  should  be 
developed  to  document:  contract  types  to  be  used; 
procurement  documents;  coordination  of  procurement 
with  schedules;  constraints  and  assumptions;  risk 
mitigation  activities  (performance  bonds,  insurances, 
etc);  and  pre-qualification  of  suppliers.  In  addition, 
specifications,  quality  standards,  performance  data  at 
work  locations,  etc,  which  are  part  of  project  scope 
statement,  should  be  described.  Inventory  management 
plays  an  important  role  in  the  procurement  management 
process. 

Provision  of  establishment  of  suitable  dispute  redressal 
system  should  be  inbuilt  to  take  care  of  any  disputes 
that  may  arise. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(5)]. 

4.3.3  Time  Management 

Time  management  aims  to  complete  the  project  within 
the  stipulated  time  period.  Time  management  essentially 
involves  the  following  processes: 

a)  Defining  project  scope  in  the  form  of  work 
breakdown  structure  to  generate  activity 
identification  and  listing, 

b)  Activity  duration  estimating, 

c)  Activity  sequencing  with  interactivity 
dependencies, 

d)  Project  schedule  development,  and 

e)  Project  schedule  control. 

Work  breakdown  structure  should  be  used  as  a  tool  to 
prepare  the  project  schedule  by  defining  the  project 
scope  and  identifying  and  listing  of  the  activities  in  the 
work  packages.  For  the  quantum  of  work  involved  in 
the  activities,  the  activity  durations  are  estimated  based 
on  the  standard  productivity  norms  for  different  trades 
of  work.  Past-documented  experience  and  expertise 
should  also  be  used  for  determination  of  the  activity 
durations  with  the  construction  technology  adopted  and 


manpower  and  equipment  resources  used.  Based  on  the 
construction  methodology  proposed  with  the 
consideration  of  project  specific  constraints,  the 
sequencing  and  interdependencies  of  the  activities  are 
detennined  and  the  graphical  representation  of  activities 
in  the  form  of  network  should  be  prepared.  The  network 
thus  prepared  should  be  analysed  to  develop  the  project 
schedule  with  information  on  early  and  late  start  and 
finishing  of  activities  with  their  available  floats  and 
the  critical  path/critical  activities  on  the  network. 
Incorporating  the  calendar  dates,  the  baseline  schedule 
may  be  finalized  with  the  incorporation  of  milestones 
for  subsequent  schedule  monitoring  and  control 
processes. 

During  the  construction  stage,  schedule  monitoring 
involves  methods  of  tracking  and  comparing  the  actual 
schedule  with  the  baseline  schedule  and  schedule 
control  activities  should  ensure  to  remove  deficiencies 
and  slippages  corrected  to  acceptable  levels. 

Project  scheduling  and  monitoring  is  a  dynamic  process 
and  periodic  schedule  updating  should  be  done  for 
effective  monitoring  and  control  process.  In  the  process, 
the  status  of  each  activity  should  be  examined.  For 
completed  activities,  actual  durations  utilized,  are 
incorporated;  and  for  activities  in  progress,  balance  to 
complete  revised  durations  and  estimated  finish  dates 
are  determined  and  incorporated.  If  the  actual  schedule 
lags  behind  the  baseline  schedule,  various  options 
should  be  considered  to  control  and  bring  back  the 
schedule  to  acceptable  levels.  The  possible  control 
actions,  which  may  be  considered,  are:  possible 
reduction  in  activity  duration  of  future  activities  with 
alternate  technology  options,  increasing  the  resources, 
alteration  in  the  construction  logic  and  activity 
sequencing,  etc. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(6)]. 

4.3.4  Cost  Management 

The  objective  of  the  project  cost  management  is  to 
ensure  that  the  project  is  completed  within  the 
authorized  budget.  The  major  processes  involved  in 
the  cost  management  are:  resource  planning,  cost 
estimation,  cost  budgeting/cost  planning  and  cost 
monitoring  and  control.  The  resource  planning  involves 
determination  of  various  types  of  resources,  such  as 
appropriate  technology,  workforce,  materials, 
equipment  and  infrastructure  facilities,  their  quantum 
and  their  requirements  during  different  stages  of  the 
project.  Preliminary  cost  estimate  with  defined  scope 
of  work  is  required  for  obtaining  the  project  sanction. 
Detailed  item  wise  cost  estimates  with  bill  of  quantities 
and  specifications  should  be  made  for  tendering  and 
subsequent  project  execution.  The  type  of  contract 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


13 


adopted  such  as  item  rate,  percentage  rate,  lump  sum 
and  cost  plus,  influences  the  cost  management  strategy. 

Most  of  the  cost  optimization  techniques  through  value 
engineering  studies  are  achieved  during  the 
preconstruction  stage  of  the  project.  Value  engineering 
is  a  useful  technique  for  application  in  cost 
management.  It  is  a  systematic  multi-disciplinary  effort 
directed  towards  analyzing  the  functions  of  project  or 
item  for  the  purpose  of  achieving  the  best  value  at  the 
lowest  overall  life  cycle  project  cost.  It  is  an  established 
technique  for  determining  value  based  decisions  rather 
than  cost  reduction  based  on  change  in  specifications. 
Suitability  of  construction  techniques,  selection  of 
equipment  for  specific  purposes,  considering 
alternative  materials  and  other  design  changes  are  some 
of  the  areas  of  application  of  value  engineering. 

During  construction  stage,  the  efforts  are  more  on 
control  mode  for  adherence  to  the  budgeted  cost.  For 
the  purpose  of  cost  control  during  execution,  the  time 
based  cost  baseline  of  the  project  which  forms  the  basis 
for  the  measurement  and  monitoring  of  cost 
performance,  should  be  generated.  The  cost  baseline 
is  generated  by  allocating  the  overall  cost  estimate  to 
individual  project  activities  based  on  the  project 
schedule.  Using  the  cost  baseline,  the  cost  control, 
which  comprises  the  following,  should  be  exercised: 

a)  Periodical  cost  reporting, 

b)  Comparison  of  the  actual  cost  against  the 
planned  cost, 

c)  Obtaining  early  warning  for  corrective  actions, 

d)  Control  and  monitoring  cost  changes, 

e)  Forecasting  of  final  cost  at  completion  based 
on  cost  trend  and  cost  changes,  and 

f)  Modification  of  the  cost  baseline  for 
authorized  cost  changes  and  preparation  of 
revised  estimates. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(7)]. 

4.3.5  Quality  Management 

Quality  management  in  construction  aims  to  achieve 
required  functional  and  physical  characteristics  of  a 
constructed  facility  through  management  actions 
including  planning,  direction  and  control.  Quality  is 
the  key  determinant  of  requirements  which  is  expressed 
through  drawings  and  specifications.  Main  function  of 
quality  management  is  to  achieve  quality  objective  of 
satisfying  requirements  through  perfonnance  evaluation 
of  construction  processes  and  ensure  that  they  are 
directed  towards  overall  quality.  Quality  management 
during  construction  stage  assumes  that  the  design  and 
specifications  comprehensively  incorporate 
requirements  of  users  and  other  stakeholders.  Prior  to 


setting  out  for  the  construction,  the  client  should 
completely  understand  the  implications  of  changes  to 
the  design  and  specifications  during  the  construction 
stage,  which  may  affect  quality. 

Although  quality  is  an  all-encompassing  concept  which 
also  has  bearing  on  time  and  cost  aspects,  the  specific 
scope  of  quality  management  may  be  limited  to  its  key 
functions  of  quality  planning,  quality  assurance  and 
quality  control.  Quality  planning  refers  to  the 
identification  of  relevant  quality  standards  and 
determining  how  to  satisfy  them.  Quality  assurance 
activities  include  consistent  evaluation  of  project 
performance  to  provide  confidence  that  the  project 
satisfies  the  relevant  quality  standards.  Quality  control 
monitors  project  results  related  to  the  compliance  to 
quality  standards  and  identifying  means  to  eliminate 
non-conformity. 

On-site  operations  constitute  most  of  the  construction 
processes.  Scope  of  quality  management  for  on-site 
operations  may  be  categorized  broadly  in  three  distinct 
stages.  In  the  receiving  stage,  materials  and  supplies 
are  inspected  and  tested  for  conformance  to  the 
specified  standards.  During  ‘in-process  stage’,  materials 
and  supplies  are  processed  to  form  project  product 
components  wherein  process  control  ensures 
conformance  to  the  specified  standards.  In  the  ‘final 
stage’,  inspections  and  tests  monitor  the  functional  and 
physical  performance  of  the  product/service  to  ensure 
that  they  satisfy  the  requirements. 

Planning  being  an  integral  part  of  the  quality 
management,  may  also  consider  efficient  site  layout 
and  its  management  for  on-site  operations.  In  addition 
to  time  and  cost  implications  of  the  site  management, 
the  quality  performance  improves  by  efficient 
organization  of  activities  by  way  of  providing  adequate 
and  appropriate  conditions  for  the  work  processes.  Site 
management  needs  to  consider  construction  technology 
constraints  with  reference  to  aspects  related  to  space 
availability  such  as  permanent  services,  access  to  site, 
temporary  services,  location  of  material  stores,  stacking 
and  storage  areas  and  plants,  fencing  and  other 
temporary  structures. 

The  various  organizations  connected  with  the  project 
should  have  their  own  quality  management  systems. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(8)]. 

4.3.6  Risk  Management 

Project  risks  have  an  impact  on  the  project  objectives 
and  need  a  planned  response.  Project  risk  management 
processes  ensure  proper  planning,  identification, 
analysis,  monitoring  and  control  to  the  best  interest  of 
the  project. 


14 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Risk  management  planning  processes  develop  an 
approach  to  risk  management  activities  which  include 
planning,  execution  and  monitoring.  A  risk  management 
plan  should  define  lead  and  support  role  responsibilities 
of  project  team  in  relation  to  management,  budgeting, 
risk  responsive  scheduling,  classification  of  risk 
activities  based  on  risk  break-down  structure  and 
explanation  of  probability  and  impact  for  risk  context. 

Risk  response  planning  determines  actions  required  for 
reducing  impact  of  risks.  Risk  responses  are  established 
and  assigned  to  appropriate  project  participants. 
Suitable  risk  mitigation  measures  should  be  evolved 
for  identified  risks. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(9)]. 

4.3.7  Communication  Management 

For  communication  management,  Management 
Information  System  (MIS)  is  used  as  an  important  tool 
for  systemized  approach  to  furnish  information.  It 
comprises  a  system  that  collects,  stores,  sorts  and 
analyses  data  to  generate  and  communicate  information. 
It  may  be  a  combination  of  manual  and  computerized 
systems. 

At  the  construction  stage  of  a  project,  there  are  many 
agencies  involved  like  client,  architect,  engineer, 
project  manager,  various  consultants,  material 
suppliers,  construction  agencies  and  sub-contractors. 
Each  agency  is  divided  into  top  level  management 
taking  policy  decisions,  middle  level  management 
monitoring  the  project  and  lower  level  management 
involved  in  day  to  day  operations  of  the  project. 

Each  level  of  management  requires  information  of 
varying  details,  at  different  periodicities  and  in  different 
formats.  Project  progress  infonnation  flows  from  lower 
level  to  the  top  level  management  and  policy  decisions 
flow  from  top  level  to  the  lower  level  management. 

MIS  integrates  the  work  and  information  flow  within 
each  agency  and  flow  of  infonnation  between  different 
agencies. 

In  construction  stage  of  the  projects,  the  information 
may  be  in  the  form  of  data  reflecting  status  of  project 
in  terms  of  actual  execution  time  for  each  activity,  cost 
incurred,  resources  used,  quality  control,  material 
management,  bills,  organization  management  and  other 
administrative  aspects  like  disputes  that  may  come  up. 
This  data  should  be  analysed  to  understand  the  overall 
progress  achieved  and  to  update  schedules  of  the 
project. 

Basic  objectives  of  MIS  of  a  construction  project  may 
be  summarized  as: 

a)  Providing  benchmark  against  which  to 


measure  or  compare  progress  and  costs,  like 
time  network  schedules,  cost  estimates, 
material  and  labour  schedules,  specifications, 
working  drawings. 

b)  Providing  an  organized  and  efficient  means 
of  measuring,  collecting,  verifying  and 
reflecting  the  progress  and  status  of  operations 
on  the  project  with  respect  to  progress,  cost, 
resources  and  quality. 

c)  Providing  an  organized,  accurate  and  efficient 
means  of  converting  the  data  from  operations 
into  information. 

d)  Reporting  the  correct  and  necessary 
information  in  the  required  format  and  at  the 
required  level  of  detail  to  managers  at  all 
levels  and  to  the  supervisors. 

e)  Identifying  and  isolating  the  most  important 
and  critical  information  at  various  stages  to 
be  communicated  to  the  managers  and 
supervisors  for  taking  decisions. 

f)  Communicating  the  information  to  the 
managers  and  supervisors  in  time  so  that 
decisions  may  be  taken  at  the  right  time. 

Total  MIS  configuration  of  the  construction  project  may 
be  divided  into  the  following  modules: 

1 )  Planning  and  scheduling  module, 

2)  Cost  control  and  accounting  module, 

3)  Trend  and  forecast  module, 

4)  Project  administrative  and  financial  module, 
and 

5)  Historical  and  documentation  module. 

All  modules  should  be  interlinked  in  flow  of 
information  and  generation  of  reports. 

For  large  public  projects,  suitable  mechanism  may  be 
established  for  communication  of  relevant  information 
to  public  at  large. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(10)]. 

4.3.8  Human  Resource  Management 

All  construction  projects  involve  large  number  of 
skilled/unskilled  persons.  Human  resources  in  a  project 
should  be  adequately  qualified,  trained  and  competent. 

Quality  of  construction  work  depends  on  the  quality  of 
labour  resource.  For  skilled  and  un-skilled  labour,  the 
requirement  for  technical  knowledge,  skill  and  general 
awareness  are  varied  for  different  construction 
processes.  Labourers  are  required  to  understand  their 
respective  responsibilities  especially  towards  the  work. 
Therefore,  construction  management  practices  should 
emphasize  on  development  of  competence  of  this 
critical  human  resource  through  training  programmes. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


15 


The  critical  activities  should  be  identified  from  the  point 
of  view  of  technological  innovations,  workmanship  and 
environmental  conditions  which  determine  labour 
behaviour  and  performance.  In  each  construction 
project,  there  are  certain  work  related  peculiarities 
which  call  for  job  specific  orientation.  There  should 
be  a  clearly  defined  competence  requirement  for  the 
workers.  Progressively,  a  formal  training  or  a  certified 
course  undertaken  should  be  a  preferred  selection 
criterion  for  the  workers.  All  efforts  should  also  be  made 
to  impart  on  site  skilling/training  of  construction 
workers  for  specific  tasks.  A  periodic  review  of  the 
performance  may  be  made  to  establish  the  nature  of 
training  required  and  methods  for  imparting  training. 
There  is  a  need  to  address  the  motivational  aspects,  for 
better  performance. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(11)]. 

4.3.9  Health  and  Safety  Management 

4.3.9. 1  Health  management  issues  include  looking  into 
the  risk  factors  to  health  of  construction  personnel  and 
providing  hygienic  conditions  at  construction  sites  and 
methods  of  their  management.  It  includes  managing, 

a)  occupational/physical  health  hazards. 

b)  short  term  as  well  as  long-term  ill  effects  of 
the  activities  and  the  working  environment  of 
the  construction  sites. 

c)  provision  of  personal  protective  equipment 
required  for  specific  health  hazards. 

d)  laying  down  of  construction  hygiene  control 
methods. 

4.3. 9.2  Safety  management  issues  include  managing 
work  processes,  equipment  and  material  handling  at 
site  for  striving  to  achieve  zero  accident  status  at  site. 
For  prevention  and  management  of  accidents,  a  proper 
organizational  and  administrative  mechanism  is 
required.  Following  steps  should  be  taken  for  achieving 
the  same: 

a)  Laying  down  of  safety  regulations  or 
mandatory  prescriptions  concerning  different 
work  processes. 

b)  Standardization  of  work  processes  and 
management  actions. 

c)  Regular  and  stipulated  inspection  of  works  and 
machinery/equipment  for  enforcement  of 
mandatory  regulations. 

d)  Providing  education  and  training  to  workers 
on  safety  issues. 

e)  Publicity  and  appeal  to  develop  safety 
consciousness. 

f)  Insurance  of  built  facilities,  construction 
personnel  and  third  party. 


g)  Regular  safety  audit  of  construction  sites  and 
post  audit  actions. 

h)  Effective  post-accident  action  including 
accident  analysis  and  reporting. 

j )  Effective  post-accident  management  including 
corrective  measures  to  avoid  repetition  of  such 
accidents. 

Safety  Officer  shall  be  appointed  in  accordance  with 
the  concerned  provisions  of  the  Building  and  Other 
Construction  Workers  (Regulation  of  Employment  and 
Conditions  of  Service)  Act,  1996.  Safety  officer  who  is 
posted  at  a  medium  to  major  construction  site  shall: 

1)  Look  after  the  safety  of  the  personnel,  safe 
handling  of  materials  and  machinery,  safe 
work  practices  and  standard  operating 
procedures. 

2)  Be  responsible  for  compliance  of  all  statutory 
obligations  of  the  employer  in  regard  to  safety 
of  personnel  and  structures. 

3)  Guide  and  assist  the  site  managers/engineers 
to  make  their  sites  safe  and  accident  free. 

4)  Train  personnel  in  construction  safety,  conduct 
safety  surveys  and  design  suitable  documents 
for  recording  and  promoting  safety  on  sites 
and  in  the  construction  industry. 

5 )  Arrange  for  safety  briefing  for  all  the  persons 
entering  the  construction  area. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(12)]. 

4.3.10  Sustainability  Management 

4.3.10.1  Sustainability  management  issues  include  the 
following: 

a)  Minimizing  adverse  environmental  impact  of 
activities,  products  and  services. 

b)  Limiting  any  adverse  impact  within  the  laws/ 
prescribed  norms  and  their  monitoring. 

c)  Safety  of  environment  while  working  with 
hazardous  materials  and  maintaining  material 
safety  data  sheets. 

d)  Management  of  disposal  of  waste  from  the 
construction  sites. 

e)  Considering  positive  environmental 
contribution  particularly  after  completion  of 
construction. 

f)  Mechanism  to  review  concerns  of  interested 
parties. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(13)]. 

4.3.11  Integration  Management 

Integration  management  aims  to  provide  processes 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


necessary  for  coordination  amongst  various 
organizations  and  their  teams  involved.  It  ensures  that 
various  organizational  teams  perform  in  an  integrated 
manner,  with  their  actions  coordinated  to  the  mutual 
interests  towards  the  project.  Integrated  management 
processes  provide  opportunities  for  resolving  conflicts 
and  competing  interests  through  appropriate  tradeoffs. 
Integration  is  necessary  where  processes  interact, 
especially  when  process  responsibilities  belong  to 
different  organizational  groups.  Such  process 
interactions  need  organizational  interfaces  to  be  defined 
and  resolved  at  an  overall  level. 

Integration  management  may  also  be  required  for 
specific  situations  when  impact  of  one  management 
function  is  a  cause  for  concern  for  other  management 
functions.  For  example,  if  there  is  a  time  delay  in 
performing  a  particular  construction  process,  it  may 
often  have  impact  on  the  cost  aspects  of  not  only  that 
process  but  other  processes  involving  other 
organizational  groups;  the  rescheduling  may  affect 
coordination  amongst  performing  groups  in  the  down¬ 
stream  processes  and  activities. 

For  detailed  guidelines,  reference  shall  be  made  to  good 
practice  [7(14)]. 

SECTION  2  CONSTRUCTION  PLANNING 
AND  SITE  MANAGEMENT 

5  PLANNING  ASPECTS 

Construction  planning  aspects  aim  to  identify  and 
develop  various  stages  of  project  execution  on  site 
which  should  be  consistent  with  the  management 
considerations.  Planning  aspects  evolve  out  of  the 
objectives  of  project  and  requirements  of  the  final 
completed  constructed  facility.  These  objectives  could 
relate  to  the  time  constraints,  cost  considerations, 
quality  standards,  safety  standards,  environmental 
considerations  and  health  considerations.  Construction 
practices  would,  then  have  to  satisfy  these  objectives 
during  construction  phase  of  the  project. 

Flaving  established  objectives  of  the  construction  phase, 
planning  determines  processes,  resources  (including 
materials,  equipment,  human  and  environmental)  and 
monitoring  system  to  ensure  that  the  practices  are 
appropriately  aligned.  Adequate  knowledge  about 
preconstruction  phase  evolution  of  project,  especially 
related  to  customer’s  requirements,  is  an  essential 
prerequisite  for  construction  planning. 

5.1  Preconstruction  Phase 

5.1.1  Besides  the  design  aspects,  preconstruction  phase 
should  also  address  all  the  issues  related  to  the 
implementation  of  the  design  at  the  site  through  suitable 
construction  strategy.  During  the  design  stage,  the  site 


conditions  should  be  fully  understood  with  anticipated 
difficulties  and  avoid  the  risk  of  subsequent  delays  and 
changes  after  the  construction  has  started. 

5.1.2  The  selection  of  construction  methods,  building 
systems  and  materials,  components,  manpower  and 
equipment  and  techniques  are  best  done  in  the 
preconstruction  phase.  Such  selection  is  influenced  by 
the  local  conditions  like  terrain,  climate,  vulnerability 
for  disasters,  etc. 

5.1.3  Construction  in  busy  localities  of  cities  needs 
special  considerations  and  meticulous  planning  due  to 
restricted  space,  adjoining  structures,  underground 
utilities,  traffic  restrictions,  noise  and  environmental 
pollution  and  other  specific  site  constraints. 

5.1.4  The  constructability  aspects  of  the  proposed 
construction  methods  needs  to  be  carefully  evaluated 
at  the  planning  stage  to  ensure  ease  of  construction 
besides  optimizing  the  construction  schedule  and 
achieving  quality,  reliability  and  maintainability  of  the 
constructed  facilities. 

5.1.5  Construction  practices  in  hilly  regions  needs  to 
take  into  considerations  the  problem  of  landslides,  slope 
stability,  drainage,  etc,  besides  ensuring  no  adverse 
impact  on  the  fragile  environmental  conditions. 

5.1.6  Durability  of  constructions  in  corrosive 
atmospheric  conditions  like  coastal  regions  and 
aggressive  ground  situations  with  high  chlorides  and 
sulphates  should  also  be  taken  care  of  with  appropriate 
construction  practices. 

5.1.7  Construction  practices  in  disaster  prone  areas  need 
specific  planning.  The  type  of  construction,  use  of 
materials,  construction  techniques  require  special 
considerations  in  such  areas. 

5.1.8  Adverse  weather  conditions  have  strong  bearing 
on  construction  phase.  Situations  wherein  constructions 
are  to  be  carried  out  in  adverse  weather  conditions, 
such  as  heavy  and  continuous  rain  fall,  extreme  hot  or 
cold  weather,  dust  storms,  etc,  the  practices  have  to 
address  the  relevant  aspects.  Accordingly,  suiting  the 
site  conditions,  the  design  and  field  operations  should 
be  adapted  or  redefined  based  on  considerations,  such 
as  the  following: 

a)  Site  layout  which  enables  accessibility  in 
adverse  weather. 

b)  Adequate  protected  storage  for  weather 
sensitive  materials/equipment. 

c)  Protection  to  personnel  from  extreme  hot/cold 
conditions. 

d)  Scheduling  to  allow  maximization  of  outdoor 
activities  during  fair  weather  conditions. 

e)  Special  design  and  construction  provisions  for 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


17 


activities  in  extreme  temperature  conditions 
like  hot  or  cold  weather  concreting,  stability 
of  false  work  in  extreme  wind  conditions 
(gusts). 

f)  Adequate  lighting  for  shorter  days  in  winter/ 
night  work. 

g)  Design  for  early  enclosure. 

5.2  Resource  Planning 

Resource  planning  aims  to  identify  requirement, 
availability  and  regulatory/control  processes  related  to 
resources.  Resource  planning  is  a  generic  expression 
but  the  actual  process  of  planning  is  specific  to  the 
resources  considered  (see  also  4.2.3.2.3). 

In  construction  phases,  the  resources  could  be 
categorized  as  materials,  manufactured  products, 
equipment  for  construction,  installation  and  fabrication, 
human  resources  as  a  part  of  overall  organization, 
information  resources  such  as  reference  standards  and 
other  practice  documents,  enviromnental  conditions  for 
work  on  site,  infrastructure  facilities  and  cash  flow. 
Therefore,  the  resource  planning  encompasses 
identification,  estimation,  scheduling  and  allocation  of 
resources.  Resource  planning  needs  to  establish  a 
control  system  for  controlling  consumption  monitoring, 
corrective  action  and  resource  reappropriation  in  the 
event  of  favourable  deviation.  Organizational 
capability,  commitment  to  the  project  requirements  and 
other  constraints  such  as  time  and  cost,  need  to  be 
considered  as  inputs  while  planning  resources. 
Techniques  of  management  and  planning  such  as 
Programme  Evaluation  and  Review  Technique  (PERT) 
and  Critical  Path  Method  (CPM)  may  be  used. 

Non-availability  of  basic  building  materials  (brick, 
stone,  aggregate,  etc)  within  reasonable  lead  would 
influence  the  construction  practice  by  alternative 
materials.  The  construction  practices  also  get  decided 
by  the  local  skills  of  the  manpower  for  construction 
activities.  The  equipment  selection  would  also  be 
governed  by  the  site  constraints.  Source  of  funding  of 
the  project  and  its  timeliness  with  reference  to 
requirement  of  cash  flow  should  also  merit 
consideration.  Therefore,  as,  the  resource  planning  is 
critical  to  the  project  viability  itself,  the  inputs  to  the 
resource  planning  need  to  be  validated  appropriately 
and  established  for  such  management.  Resource 
planning  should  establish  a  proper  system  of  data 
collection  so  as  to  facilitate  effective  resources  control 
mechanism.  Resource  planning  responsibility  has  to  be 
specifically  defined  in  the  overall  organizational  setup. 

5.3  Construction  Phase 

5.3.1  Organizational  Structure 

The  site  management  should  be  carried  out  through 


suitable  site  organization  structure  with  roles  and 
responsibilities  assigned  to  the  construction  personnel 
for  various  construction  related  functions. 

5.3.2  Site  Management 

5.3.2. 1  Site  layout 

The  layout  of  the  construction  site  should  be  carefully 
planned  keeping  in  view  the  various  requirements  of 
construction  activities  and  the  specific  constraints  in 
terms  of  its  size,  shape,  topography,  traffic,  and  other 
restrictions,  in  public  interest.  A  well  planned  site  layout 
would  enable  safe  smooth  and  efficient  construction 
operations.  The  site  layout  should  take  into 
considerations  the  following  factors: 

a)  Easy  access  and  exit,  with  proper  parking  of 
vehicle  and  equipment  during  construction 

b)  Properly  located  material  stores  for  easy 
handling  and  storage. 

c)  Adequate  stack  areas  for  bulk  construction 
materials. 

d)  Optimum  location  of  plants  and  equipment 
(batching  plants,  etc). 

e)  Layout  of  temporary  services  (water,  power, 
power  suppression  unit,  hoists,  cranes, 
elevators,  etc). 

f)  Adequate  yard  lighting  and  lighting  for  night 
shifts. 

g)  Temporary  buildings;  site  office  and  shelter 
for  workers  ( see  14)  with  use  of  non¬ 
combustible  materials  as  far  as  possible 
including  emergency  medical  aids. 

h)  Roads  for  vehicular  movement  with  effective 
drainage  plan. 

j)  Construction  safety  with  emergency  access 
and  evacuations  and  security  measures. 

k)  F abrication  yards  for  reinforcement  assembly, 
concrete  precasting  and  shuttering  materials. 

m)  Fencing,  barricades  and  signages. 

5.3.2.2  Access  for  firefighting  equipment  vehicles 

Access  for  firefighting  equipment  shall  be  provided  to 
the  construction  site  at  the  start  of  construction  and 
maintained  until  all  construction  work  is  completed. 
Free  access  from  the  street  to  fire  hydrants/static  water 
tanks,  where  available,  shall  be  provided  and 
maintained  at  all  times.  No  materials  for  construction 
shall  be  placed  within  3  m  of  hydrants/static  water  tanks. 
During  building  operations,  free  access  to  permanent, 
temporary  or  portable  first-aid  firefighting  equipment 
shall  be  maintained  at  all  times. 

5.3. 2.3  Access  to  the  upper  floors  during  construction 
In  all  buildings  over  two  storeys  high,  at  least  one 


18 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


stairway  shall  be  provided  in  usable  condition  at  all 
times.  This  stairway  shall  be  extended  upward  as  each 
floor  is  completed.  There  shall  be  a  handrail  on  the 
staircase. 

5.3.2.4  Electrical  installations 

Electrical  installations,  both  permanent  and  temporary, 
for  construction  and  demolition  sites,  including 
electrical  installations  for  transportable  construction 
buildings  (site  sheds)  shall  be  in  accordance  with  12  of 
Part  8  ‘Building  Services,  Section  2  Electrical  and 
Allied  Installations’  of  the  Code. 

5.3.3  Construction  Strategy  and  Construction 
Sequence 

Construction  strategy  and  construction  methods  are  to 
be  evolved  at  the  planning  and  design  stage  specific  to 
the  conditions  and  constraints  of  the  project  site  and 
implemented  by  the  site  management  personnel  to 
ensure  ease  of  construction  and  smooth  flow  of 
construction  activities.  Sites  of  high  water  table 
conditions  with  aggressive  chemical  contents  of  subsoil 
needs  special  design  considerations.  Buildings  with 
basement  in  sites  of  high  water  table  should  be  planned 
with  dewatering  scheme  with  appropriate  construction 
sequence.  Duration  of  dewatering  should  continue  till 
sufficient  dead  loads  are  achieved  to  stabilize  the 
buoyancy  loads  with  adequate  factor  of  safety.  The 
construction  sequence  should  be  planned  taking  into 
consideration  the  following  aspects: 

a)  Availability  of  resources  (men,  material  and 
equipment); 

b)  Construction  methods  employed  including 
prefabrication; 

c)  Planned  construction  time; 

d)  Design  requirements  and  load  transfer 
mechanism; 

e)  Stability  of  ground  like  in  hilly  terrain; 

f)  Ensuring  slope  stability  with  retaining 
structure  before  the  main  construction; 

g)  Installation  and  movement  of  heavy 
equipment  like  cranes  and  piling  equipment; 

h)  Effect  of  weather;  and 

j)  Minimum  time  to  be  spent  on  working  below 
ground  level. 

SECTION  3  CONSTRUCTION  PRACTICES 

6  CONSTRUCTION  CONTROL  AND 
PRACTICES 

6.1  Professional  Services  and  Responsibilities 

The  responsibility  of  professionals  with  regard  to 
planning,  designing  and  supervision  of  building 


construction  work,  etc  and  that  of  the  owner  shall  be  in 
accordance  with  Part  2  ‘Administration’  of  the  Code. 
All  applications  for  pennits  and  issuance  of  certificates, 
etc  shall  be  as  given  in  Part  2  ‘Administration’  of  the 
Code.  Employment  of  trained  workers  shall  be 
encouraged  for  building  construction  activity. 

6.2  Site  Preparation 

6.2.1  While  preparing  the  site  for  construction,  bush 
and  other  wood,  debris,  etc,  shall  be  removed  and 
promptly  disposed  of  so  as  to  minimise  the  attendant 
hazards. 

6.2.2  Temporary  buildings  for  construction  offices  and 
storage  shall  be  so  located  as  to  cause  the  minimum 
fire  hazards  and  shall  be  constructed  from  non¬ 
combustible  materials  as  far  as  possible. 

6.3  Habitat  for  Construction  Workers  at  Site 

The  habitat  and  other  welfare  measures  for  construction 
workers  shall  meet  the  requirements  specified  in  14. 

6.4  Construction  of  All  Elements 

6.4.1  Construction  of  all  elements  of  a  building  shall 
be  in  accordance  with  good  practice  [7(15)].  It  shall 
also  be  ensured  that  the  elements  of  structure  satisfy 
the  appropriate  fire  resistance  requirements  as  specified 
in  Part  4  ‘Fire  and  Life  Safety’  of  the  Code,  and  quality 
of  building  materials/components  used  shall  be  in 
accordance  with  Part  5  ‘Building  Materials’  of  the 
Code. 

6.4.2  Construction  of  all  accessibility  features/elements 
in  a  building  and  its  built  environment  shall  be  as  per 
the  requirements  given  in  13  of  Part  3  ‘Development 
Control  Rules  and  General  Building  Requirements’  of 
the  Code. 

6.4.3  All  mechanical,  electrical  and  plumbing  (MEP) 
and  other  services  in  a  building  shall  be  installed  in 
accordance  with  approved  designs  as  per  Part  8 
‘Building  Services’  of  the  Code  and  Part  9  ‘Plumbing 
Services  including  Solid  Waste  Management’  of  the 
Code.  Proper  sequencing  of  installation  of  various 
services  shall  be  done  for  ensuring  smooth  construction 
activities. 

6.4.4  Necessary  temporary  works  required  to  enable 
permanent  works,  shall  be  executed  in  accordance 
with  7. 

6.5  Low  Income  Housing 

For  low  income  housing,  appropriate  planning  and 
selection  of  building  materials  and  techniques  of 
construction  have  to  be  judiciously  done  and  applied 
in  practice.  Requirements  of  low  income  housing 
specified  in  Part  3  ‘Development  Control  Rules  and 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


19 


General  Building  Requirements’  of  the  Code  shall  be 
followed.  However,  all  requirements  regarding 
structural  safety,  health  safety  and  fire  safety  shall  be 
in  accordance  with  this  Part. 

6.6  Use  of  New/ Alternative  Construction  Techniques 

The  provisions  of  this  Part  are  not  intended  to  prevent 
use  of  any  construction  techniques  including  any 
alternative  materials,  not  specifically  prescribed  by  the 
Code,  provided  any  such  alternative  has  been  approved. 
The  Authority  may  approve  any  such  alternative,  such 
as,  ferrocement  construction;  stretcher  bond  in  filler 
slab;  glass  fibre  reinforced  gypsum  (GFRG)  panel 
system  using  composite  of  GFRG  panel  and  reinforced 
concrete;  pre-engineered  steel  structures  with 
reinforced  concrete  expanded  polystyrene  core  based 
panel/other  in-fill  walls;  light  gauge  steel  framed 
structures  with  suitable  water  resistant  wall  panels  like 
cement  bonded  particle  board,  provided  it  is  found  that 
the  proposed  alternative  is  satisfactory  and  conforms 
to  the  provisions  of  relevant  parts  regarding  material, 
design  and  construction  and  that  material,  method,  or 
work  offered  is,  for  the  purpose  intended,  at  least 
equivalent  to  that  prescribed  in  the  Code  in  quality, 
strength,  compatibility,  effectiveness,  fire  and  water 
resistance,  durability  and  safety. 

6.7  Urban  Roads/City  Roads  Planning  and 
Construction 

6.7.1  The  urban  roads,  which  are  commonly  known  as 
city  roads/streets  have  been  under  constant 
development.  The  emphasis  has  been  primarily  on 
providing  essentially  required  width  of  metalled  surface 
for  the  movement  of  vehicles  (both  motorized  and  non- 
motorized).  Footpaths  of  various  widths  and  heights 
are  required  to  be  provided. 

The  space  between  the  buildings  and  the  city  roads 
should  be  treated  as  valuable  and  important  space 
allowing  for  a  comfortable  and  safe  use  by  the 
pedestrians,  hawkers,  cyclists  including  non-motorized 
vehicle  (NMV)  drivers,  and  adequate  space  for 
drainage,  utilities,  street  lighting  poles,  transformers 
and  trees.  Thus,  the  objective  should  be  to  create  urban 
streets/roads  that  are  efficiently  planned,  safe  for 
vehicles  as  well  as  pedestrians,  universally  user  friendly, 
and  sustainable. 

The  elements  required  in  an  efficiently  planned  street, 
such  as,  kerb  stones;  kerb  channels;  kerb  ramps;  tactile 
ground  surface  indicators;  silt  chambers  with  manhole 
cover;  drain  cover  slabs;  drain  manhole  covers;  service 
pipes;  manhole  covers  for  electrical  services;  manhole 
covers  for  telecom  services;  cycle  tracks  (NMV); 
bollards  across  pedestrian  paths;  tree  gratings;  lighting 
poles  on  main  roads  and  service  roads;  table  tops  on 
free  left  turns;  pedestrian  paths  at  intersections/ 


T-junctions;  pedestrian  paths  on  traffic  islands; 
pedestrian  paths  across  central  verge;  pedestrian  paths 
near  rotaries  (un-signaled);  pedestrian  paths  below 
flyovers;  signages;  traffic  signals;  cable  ducting  by 
discoms;  central  verge  irrigation  system;  central  verge, 
footpath  and  traffic  islands  plantation;  street  furniture; 
bus  queue  shelters;  public  art,  public  toilets,  etc.  should 
be  identified.  These  elements  should  be  integrated  at 
the  planning  stage,  indicating  the  methodology  of 
execution,  taking  care  of  the  following  while  complying 
with  the  relevant  rules/regulations: 

a)  Road  cross-section  planning  based  on  land- 
use  with  emphasis  on  smooth  vehicular 
movements. 

NOTE  —  This  may  be  achieved  by  rationalizing  lane  widths 
based  on  norms  laid  down  by  Indian  Roads  Congress. 

b)  Design  of  road  intersections,  fixing  of 
geometries  of  roads,  providing  provision  of 
entry  and  exits  from  the  service  roads. 

c)  Coordination  between  the  traffic  police, 
transport  authorities  and  the  executing 
agencies  to  be  ensured  for  efficient  location 
of  traffic  signals,  zebra  crossings  and  the  bus 
queue  shelters  and  the  pickup  stands  for  the 
para-transport. 

d)  Standardization  of  kerb  stones,  kerb  ramps  and 
kerb  channels. 

e)  Appropriate  selection  of  materials,  like,  paver 
blocks,  tiles,  stone  slabs  or  plain  cement 
concrete  for  footpaths,  plazas,  etc,  so  that  they 
add  to  aesthetics  of  buildings  and  roads. 

f)  Standardization  of  access  manhole  covers  for 
various  utilities. 

g)  Providing  footpath  at  one  level  by  adjusting 
the  drain  cover  slab  levels. 

h)  Integration  of  bus  queue  shelters  with  the 
footpath. 

j)  Pedestrian  friendly  access  across  the  roads  to 
the  foot-over  bridges,  subways  and  public 
toilets. 

k)  Access  to  gates  of  residential/commercial 
properties  integrated  with  the  road  through  the 
footpath  in  front. 

m)  Sharing  of  NMV  with  footpath  necessary  at 
many  locations. 

n)  Adequate  provision  of  public  conveniences 
and  dust  bins. 

p)  Street  lighting  for  proper  illumination  of  roads 
and  service  roads  including  modifications  of 
street  lighting  along  with  central  verge  and  the 
service  roads  blocked  by  existing  trees. 

q)  Low  height  plantation  on  central  verges, 
avoiding  plantation  of  trees. 


20 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


r)  Removal  of  crooked  trees  on  footpaths  for 
proper  and  safe  utilization  of  footpath. 

s)  Removal  of  trees  obstructing  the  carriage  ways 
and  their  replantation,  wherever  feasible. 

t)  Freeing  of  trees  embedded  in  the  compound 
wall/dwarf  walls  on  footpaths  to  save  both  the 
trees  and  the  walls. 

u)  Providing  planters  in  the  central  verge  in  the 
deck  portion  of  flyover  to  ensure  proper  glare 
cutting  during  night  hours  and  improving 
aesthetics  during  the  day. 

w)  Proper  location  of  signage  boards  so  as  to  be 
safe  from  moving  traffic  near  the  footpath 
edges  and  give  clear  visibility. 

y)  Selection,  procurement  and  installation  of 
street  furniture. 

z)  Selection,  procurement  and  installation  in 
respect  of  accessibility  features  as  per  the 
requirements  given  in  13  of  Part  3 
‘Development  Control  Rules  and  General 
Building  Requirements’  of  the  Code. 

NOTE  —  The  relevant  standards/publications  of  Indian  Roads 
Congress  may  be  referred  to. 

6.7.2  The  road  work  zones  are  areas  of  conflict  between 
normal  operating  traffic,  construction  workers,  road 
building  machineries  and  construction  traffic.  If  it  is  a 
construction  of  new  road,  normal  operating  traffic  will 
not  be  there  but  the  care  has  to  be  taken  to  avoid  and  or 
remove  conflicts  between  workers  and  construction 
machineries  and  construction  traffic.  Problem  becomes 
more  serious  if  it  is  an  urban  road  with  significant 
proportion  of  vulnerable  road  users.  The  road  work 
zones  and  the  traffic  around  them  should  be  so  planned 
and  managed  so  as  to  ensure  traffic  safety,  facilitate 
smooth  and  efficient  flow  of  traffic  and  also  provide 
safe  working  environment  for  the  workers. 

NOTE  —  For  guidance  on  management  of  pedestrians/cyclists/ 
vehicles  near  road  construction  sites,  reference  may  be  made 
to  IRC  SP  55  :  2014  ‘Guidelines  on  traffic  management  in  work 
zones’. 

6.8  Measures  against  pollution  and  hazard  due  to  dust, 
smoke  and  debris,  such  as  screens  and  barricading  shall 
be  installed  at  the  site  during  construction.  Plastic/ 
tarpaulin  sheet  covers  shall  be  used  for  trucks 
transporting  fine  materials  liable  to  cause  environmental 
pollution. 

7  TEMPORARY  WORKS 

7.1  The  construction  of  most  types  of  permanent  works 
requires  the  use  of  some  form  of  temporary  works. 
Temporary  works  are  the  parts  of  a  construction  project 
that  are  needed  to  enable  the  permanent  works  to  be 
built.  Usually  the  temporary  works  are  removed  after 
use,  for  example,  access,  scaffolds,  props,  shoring, 


excavation  support,  false  work  and  formwork, 
etc.  Sometimes  the  temporary  works  are  incorporated 
into  the  permanent  works,  for  example,  haul  road 
foundations  and  crane  or  piling  platforms  which  may 
be  used  for  hard  standing  or  road  foundations.  The  same 
degree  of  care  and  attention  should  be  given  to  the 
design  and  construction  of  temporary  works  as  to  the 
design  and  construction  of  the  permanent  works. 
Considering  that  as  temporary  works  may  be  in  place 
for  only  a  short  while,  there  is  a  tendency  to  assume 
they  are  less  important,  which  is  incorrect.  Lack  of  care 
in  design,  selection,  assembly,  etc,  leaves  temporary 
works  liable  to  fail  or  collapse.  While  organizing  the 
temporary  works,  aspects  as  given  below  should  be 
followed: 

a)  The  person  organizing  the  temporary  works 
should  be  aware  of  the  problems  that  can  occur 
at  each  stage  of  the  process  and  how  to  prevent 
these.  They  need  to  coordinate  design, 
selection  of  equipment,  appointment  of 
contractors,  supervision  of  work,  checking 
completion,  authorization  to  load  and 
removal. 

b)  If  so  required,  a  temporary  works  co-ordinator 
(TWC)  may  be  employed  in  case  of  medium 
and  large  projects,  whose  requisite 
qualification  and  experience  should  be 
specified.  The  role  of  TWC  and  supervisor 
should  be  decided.  The  coordinator  shall  have 
adequate  field  training  for  temporary  works. 
The  contractor  shall  ensure  that  work  is 
allocated  and  carried  out  in  a  manner  that  does 
not  create  unacceptable  risk  of  harm  to 
workers  or  members  of  the  public.  On 
projects  with  relatively  simple  temporary 
works  needs,  a  TWC  may  be  avoided, 
however,  it  shall  be  ensured  that  temporary 
works  are  properly  managed. 

c)  The  cost  of  any  temporary  works  is  generally 
included  in  the  build-up  of  the  tender. 

d)  Temporary  works  are  often  taken  from  site  to 
site  and  re-used  and  it  is  important  to  consider 
the  robustness  of  components  in  their  design. 
However,  temporary  works  that  are  designed 
only  to  be  used  during  construction  shall  not 
be  removed  until  the  satisfactory  safety  criteria 
for  their  use  has  been  met. 

e)  Proper  planning  and  co-ordination  should  be 
done  in  respect  of  sequence  and  timely 
execution  of  temporary  works,  as  also  for 
ensuring  that  they  are  correctly  installed,  used, 
checked  and  maintained. 

f)  In  each  of  the  cases  of  temporary  works,  the 
person  organizing  the  temporary  works  should 
assess  the  soil  conditions  to  be  sure  that  it  is 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


21 


suitable  for  the  equipment  involved,  and  check 
that  any  assumptions  made  in  the  calculations 
for  the  standard  solution  are  valid  for  this 
particular  situation  and  the  conditions  on  site. 
On  a  simple  job,  the  supplier’s  data  will  allow 
an  experienced  person  to  consider  the 
necessary  issues  without  further  calculation. 

g)  Propping  using  standard  equipment  such  as 
screw  props  (acrows)  needs  careful 
consideration.  To  select  the  type,  size,  number 
and  decide  spacing,  information  is  needed 
about  the  loads  that  will  act  on  the  props.  This 
will  include  the  wall  above  and  the  additional 
load  from  any  other  floor  or  roof  beams,  etc, 
that  enter  the  wall  above  or  close  to  the 
opening.  Even  with  proprietary  equipment, 
the  support  system  shall  be  worked  out. 

h)  A  local  failure  within  the  temporary 
works  should  not  initiate  a  global  collapse  of 
the  structure.  Therefore,  additional  care  should 
be  taken  while  removing  temporary  works. 

The  different  types  of  temporary  works  can  be 
scaffolding,  crane  supports,  falsework,  formwork,  and 
trench  support.  Detailed  knowledge  about  each  type  of 
temporary  work  is  necessary  for  safe  construction.  The 
requirements  as  given  in  7.2  to  7.6  shall  be  satisfied  in 
case  of  temporary  works. 

Proprietary  equipment  supplier  should  be  identified  and 
approved.  It  should  be  ascertained,  whether  following 
has  been  performed: 

1)  They  have  designed  the  foundations, 

2)  Any  assumption  made  that  have  to  be 
confirmed/investigated, 

3)  Independent  checking  done  and  by  whom, 

4)  Status  of  drawings,  and 

5)  Procedures  checked  at  site. 

In  management  of  temporary  works,  the  owner/client 
has  to  ensure, 

i)  checks  on  competence  on  designers; 

ii)  steps  taken  to  ensure  co-operation  between  the 
permanent  and  temporary  works  designers; 

iii)  coordination  at  site  meetings;  and 

iv)  advise  clients  on  the  suitability  of  the  initial 
construction  phase  plan,  that  is,  the 
arrangements  for  controlling  significant  site 
risks. 

7.2  Scaffolding 

Scaffolding  includes  providing  a  temporary  safe 
working  platform  for  erection,  maintenance, 
construction,  repair,  access,  and  inspection.  Scaffolding 
and  their  erection  shall  be  in  accordance  with  the  good 
practice  [7(16)]. 


7.3  Tower  Cranes 

Tower  cranes  are  usually  supplied  on  a  hire  basis,  with 
the  client  being  responsible  for  the  design  and 
construction  of  the  base  upon  which  the  crane  is  erected. 
Details  of  loading  are  provided  by  the  crane  supplier 
and  the  base  is  most  commonly  designed  as  a  temporary 
structure,  though  sometimes  a  crane  base  is 
incorporated  into  the  permanent  structure  to  save  on 
cost  and  time. 

Loads  are  given  in  two  forms,  ‘in  service’  loads,  where 
the  crane  is  functioning  and  wind  speeds  are  restricted 
(that  is,  cranes  will  not  operate  at  high  wind  speeds), 
and  ‘out  of  service’  loads,  where  the  crane  is  not  being 
used  but  maximum  wind  speeds  may  occur. 

The  location  for  a  crane  should  be  carefully  selected 
to  provide  a  maximum  working  radius,  and  when  two 
cranes  are  being  used  on  the  same  site,  mast  heights 
and  jib  lengths  shall  be  considered. 

Cranes  should  typically  be  structured  around  two  rails 
at  their  base  between  4.5  m  and  1 0  m  apart  with  wheels 
in  each  corner.  Cranes  should  not  normally  be  tied 
down,  so  sufficient  kentledge  should  be  provided  so  as 
to  ensure  that  vertical  loading  from  the  crane  passes 
through  the  rails  and  into  the  foundation. 
The  foundation  shall  be  so  designed  that  the  unfactored 
loading  from  the  crane  and  the  unfactored  pressure  is 
less  than  the  allowable  bearing  pressure  of  the  soil. 

Various  foundation  types  can  be  selected  depending  on 
the  ground  conditions.  Where  possible  a  structural  fill 
can  be  compacted  and  used  to  support  a  crane  with  the 
load  spreading  through  layers  of  track  support  at  45° 
in  to  the  soil  strata  below.  When  loads  from  the  crane 
increase,  reinforced  concrete  foundations  may  be 
required.  This  can  involve  a  series  of  reinforced 
concrete  beams  used  to  support  line  loads  as  a  result  of 
the  crane  loading. 

When  ground  conditions  are  particularly  poor, 
pile  foundations  may  be  necessary.  The  design  shall 
ensure  that  reinforcement  at  the  top  of  the  pile  top 
should  not  cause  problems  for  positioning  the  mast  base 
section  of  the  crane. 

Tower  cranes  shall  embody  all  fundamental  principles 
of  design  in  accordance  with  the  good  practice  [7(  17)] 
so  as  to  secure  reliability  and  safety  in  operation.  The 
particular  requirements  for  controls  for  tower  cranes 
and  the  arrangement  of  basic  control  used  for 
positioning  loads  shall  be  in  accordance  with  the  good 
practice  [7(18)]. 

7.4  Falsework 

Falsework  involves  a  temporary  structure  used  to 


22 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


support  other  permanent  structures  until  they  can 
support  themselves.  Falsework  shall  be  designed  and 
erected  in  accordance  with  the  good  practice  [7(19)]. 

7.5  Formwork 

Formwork  is  the  term  used  for  a  temporary  mould  into 
which  concrete  is  poured  and  formed.  Traditional 
formwork  is  fabricated  using  timber,  but  it  can  also  be 
constructed  from  steel,  glass  fiber  reinforced  plastics 
and  other  materials. 

Timber  formwork  is  normally  constructed  on  site 
using  timber  and  plywood.  It  is  easy  to  produce, 
although  it  can  be  time  consuming  for  larger  structures. 
Re-usable  plastic  formwork  is  generally  used  for  quick 
pours  of  concrete.  The  formwork  is  assembled  either 
from  interlocking  panels  or  from  a  modular  system  and 
is  used  for  relatively  simple  concrete  structures.  It  is 
not  as  versatile  as  timber  formwork  due  to  the 
prefabrication  requirements  and  is  best  suited  for  low- 
cost,  repetitive  structures  such  as  mass  housing 
schemes. 

Stay-in-place  structural  formwork  is  generally 
assembled  on  site  using  prefabricated  fibre-reinforced 
plastic.  It  is  used  for  concrete  columns  and  piers  and 
stays  in  place,  acting  as  permanent  axial  and  shear 
reinforcement  for  the  structural  member.  It  also 
provides  resistance  to  environmental  damage  to  both 
the  concrete  and  reinforcing  bars.  Proprietary  systems 
are  used  to  support  vertical  formwork  while  concrete 
cures,  consisting  of  series  of  tubes  and  ties. 

When  selecting  formwork  the  type  of  concrete  and 
temperature  of  the  pour  are  important  considerations 
as  they  both  effect  the  pressure  exerted  on  the 
formwork.  Striking  of  formwork  shall  be  governed  by 
Part  6  ‘Structural  Design,  Section  5  Concrete: 
Subsection  5A  Plain  and  Reinforced  Concrete’  of  the 
Code. 

Fligh  quality  workmanship  and  inspection  are 
necessary  to  ensure  a  high  standard  of  work  including 
finish. 

7.6  Trench  Support 

A  trench  is  defined  as  an  excavation  when  its  length 
greatly  exceeds  its  depth.  Shallow  trenches  are  usually 
considered  to  be  less  than  6  m  deep  and  deep  trenches 
have  depth  greater  than  6  m.  Depending  on  the 
dimensions  of  a  trench,  excavation  can  either  be  carried 
out  by  hand  or  by  using  a  mechanical  digger.  Trenches 
are  commonly  required  to  allow  services,  pipelines 
or  foundations  to  be  laid. 

Water  ingress  into  the  trench  is  often  a  major  issue  and 
ground  water  table  locations  and  soil  strata  should  be 
investigated  before  any  extensive  excavation  takes 


place.  Over  short  periods  of  time,  for  relatively  shallow 
depths  most  soil  types  will  stand  almost  vertically 
without  any  problems.  Flowever,  trenches  other  than 
those  which  are  relatively  shallow  may  require  a  trench 
support  scheme.  Traditionally,  trenching  involved 
using  timber  to  support  horizontal  and  vertical  soil 
loads  and  this  technique  is  still  used  today.  Timber 
trenching  is  generally  used  for  low  risk,  narrow 
trenches,  shafts  or  headings.  The  timber  solutions 
require  good  workmanship  and  are  reasonably  labour- 
intensive;  however,  they  are  versatile  and  the 
equipment  required  is  easy  to  handle  and  transport. 

Trench  boxes  are  suitable  for  low-risk  situations  in 
stable,  dry  ground  and  can  be  placed  in  pre-excavated 
trenches  or  installed  using  the  ‘dig  and  push’  technique. 
The  system  requires  at  least  two  struts  at  each  panel 
for  stability  which  should  be  considered  when  access 
is  required  for  construction  work  or  piping. 

Trench  sheets  are  the  most  adaptable  of  the  systems 
available,  and  are  most  commonly  used  to  retain  poorer 
soil.  They  can  support  deeper  trenches  with  larger 
surcharges  and  provide  a  continuous  support.  They 
require  multiple  levels  of  strut  support  and  the 
slenderness  of  the  sheets  can  often  limit  the  depth  of 
the  trench  as  they  are  installed  by  light  machinery  and 
could  buckle  under  large  vertical  loads. 

While  making  deep  excavation  near  an  existing 
structure,  it  is  necessary  that  the  lateral  force  caused 
by  the  existing  structure  should  be  taken  care  of. 

Trench  supports  shall  be  provided  in  accordance  with 
the  good  practice  [7(20)]. 

8  STORAGE,  STACKING  AND  HANDLING 
PRACTICES 

8.1  General 

8.1.1  Planning  and  Storage  Layout 

8.1. 1.1  For  any  site,  there  should  be  proper  planning 
of  the  layout  for  stacking  and  storage  of  different 
materials,  components  and  equipment  with  proper 
access  and  proper  manoeuvrability  of  the  vehicles 
carrying  the  material.  While  planning  the  layout,  the 
requirements  of  various  materials,  components  and 
equipment  at  different  stages  of  construction  shall  be 
considered. 

8.1. 1.2  Materials  shall  be  segregated  as  to  kind,  size 
and  length  and  placed  in  neat,  orderly  piles  that  are 
safe  against  falling.  If  piles  are  high  they  shall  be 
stepped  back  at  suitable  intervals  in  height.  Piles  of 
materials  shall  be  arranged  so  as  to  allow  a  passageway 
of  not  less  than  1  m  width  in  between  the  piles  or  stacks 
for  inspection  or  removal.  All  passageways  shall  be 
kept  clear  of  dry  vegetation. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


23 


8. 1.1. 3  Materials  shall  be  stored,  stacked  and  handled 
in  such  a  manner  as  to  prevent  deterioration  or  intrusion 
of  foreign  matter  and  to  ensure  the  preservation  of  their 
quality  and  fitness  for  the  work. 

8. 1.1. 4  Materials  shall  be  stacked  on  well  drained,  firm 
and  unyielding  surface.  Materials  shall  not  be  stacked 
so  as  to  impose  any  undue  stresses  on  walls  or  other 
structures. 

8. 1.1. 5  Materials  shall  be  stacked  in  such  a  manner  as 
not  to  constitute  a  hazard  to  passerby.  At  such  places 
the  stacks  shall  have  suitable  warning  signs  in  day  time 
and  red  lights  on  and  around  them  at  night. 

8. 1.1. 6  Stairways,  passageways  and  gangways  shall  not 
become  obstructed  by  storage  of  building  materials, 
tools  or  accumulated  rubbish. 

8.1.2  Protection  Against  Atmospheric  Agencies 

Materials  stored  at  site,  depending  upon  the  individual 
characteristics,  shall  be  protected  from  atmospheric 
actions,  such  as  rain,  sun,  winds  and  moisture,  to  avoid 
deterioration. 

8.1.3  Protection  Against  Fire  and  Other  Hazards 

8.1.3. 1  Materials,  like  timber,  bamboo,  coal,  paints, 
etc,  shall  be  stored  in  such  a  way  that  there  may  not  be 
any  possibility  of  fire  hazards.  Inflammable  materials 
like  kerosene  and  petrol,  shall  be  stored  in  accordance 
with  the  relevant  rules  and  regulations  so  as  to  ensure 
the  desired  safety  during  storage.  Stacks  shall  not  be 
piled  so  high  as  to  make  them  unstable  under  fire 
fighting  conditions  and  in  general  they  shall  not  be  more 
than  4.5  m  in  height.  The  provisions  given  in  good 
practice  [7(21)]  shall  be  followed.  Explosives  like 
detonators  shall  be  stored  in  accordance  with  the 
existing  regulations  of  The  Explosives  Act,  1884. 

8. 1.3. 2  Materials  which  are  likely  to  be  affected  by 
subsidence  of  soil  like  precast  beams,  slabs  and  timber 
of  sizes  shall  be  stored  by  adopting  suitable  measures 
to  ensure  unyielding  supports. 

8.1.3.3  Materials  liable  to  be  affected  by  floods,  tides, 
etc,  shall  be  suitably  stored  to  prevent  their  being 
washed  away  or  damaged  due  to  floods,  tides,  etc. 

8.1.4  Manual  Handling 

When  heavy  materials  have  to  be  handled  manually 
each  workman  shall  be  instructed  by  his  foreman  or 
supervisor  for  the  proper  method  of  handling  such 
materials.  Each  workman  shall  be  provided  with 
suitable  equipment  for  his  personal  safety  as  necessary. 
All  workers  shall  wear  adequate  clothing  to  protect 
themselves  from  direct  sun-rays  and  other  irritants. 
Supervisors  shall  also  take  care  to  assign  enough  men 
to  each  such  job  depending  on  the  weight  and  the 
distance  involved. 


8.2  Storage,  Stacking  and  Handling  of  Materials 

8.2.1  The  storage,  stacking  and  handling  of  materials 
generally  used  in  construction  shall  be  as  given  in  8.2.2 
to  8.2.31,  which  have  been  summarized  in  the  form  of 
a  check  list  in  Annex  A.  Exposure  to  asbestos  fibres/ 
dust  is  known  to  be  harmful  to  health  of  human  beings. 
Prescribed  guidelines  in  accordance  with  good  practice 
[7(22)]  shall  be  followed  for  handling  and  usage  of 
asbestos  cement  products. 

8.2.2  Cement 

a)  Storage  and  stacking  —  Cement  shall  be  stored  at 
the  work  site  in  a  building  or  a  shed  which  is  dry,  leak- 
proof  and  as  moisture-proof  as  possible.  The  building 
or  shed  for  storage  should  have  minimum  number  of 
windows  and  close  fitting  doors  and  these  should  be 
kept  closed  as  far  as  possible. 

Cement  received  in  bags  shall  be  kept  in  such  a  way 
that  the  bags  are  kept  free  from  the  possibility  of  any 
dampness  or  moisture  coming  in  contact  with  them. 
Cement  bags  shall  be  stacked  off  the  floor  on  wooden 
planks  in  such  a  way  as  to  keep  them  about  150  mm  to 
200  mm  clear  above  the  floor.  The  floor  may  comprise 
lean  cement  concrete  or  two  layers  of  dry  bricks  laid 
on  a  well  consolidated  earth.  A  space  of  600  mm 
minimum  shall  be  left  around  between  the  exterior  walls 
and  the  stacks  (see  Fig.  3).  In  the  stacks  the  cement 
bags  shall  be  kept  close  together  to  reduce  circulation 
of  air  as  much  as  possible.  Owing  to  pressure  on  bottom 
layer  of  bags  sometimes  ‘warehouse  pack’  is  developed 
in  these  bags.  This  can  be  removed  easily  by  rolling 
the  bags  when  cement  is  taken  out  for  use.  Lumped 
bags,  if  any  should  be  removed  and  disposed  of. 

The  height  of  stack  shall  not  be  more  than  1 0  bags  to 
prevent  the  possibility  of  lumping  up  under  pressure. 
The  width  of  the  stack  shall  be  not  more  than  four  bags 
length  or  3  m.  In  stacks  more  than  8  bags  high,  the 
cement  bags  shall  be  arranged  alternately  length-wise 
and  cross-wise  so  as  to  tie  the  stacks  together  and 
minimise  the  danger  of  toppling  over.  Cement  bags  shall 
be  stacked  in  a  manner  to  facilitate  their  removal  and 
use  in  the  order  in  which  they  are  received;  a  table 
showing  date  of  receipt  of  cement  shall  be  put  on  each 
stack  to  know  the  age  of  cement. 

For  extra  safety  during  monsoon,  or  when  it  is  expected 
to  store  for  an  unusually  long  period,  the  stack  shall  be 
completely  enclosed  by  a  water  proofing  membrane 
such  as  polyethylene,  which  shall  close  on  the  top  of 
the  stack.  Care  shall  be  taken  to  see  that  the 
waterproofing  membrane  is  not  damaged  any  time 
during  the  use. 

Cement  in  gunny  bags,  paper  bags  and  polyethylene 
bags  shall  be  stored  separately. 


24 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


PLAN 


A  =  PLANKS 
B  =  WOODEN  BATTENS 
C  =  150  mm  THICK  LEAN  CEMENT 
CONCRETE  OR  DRY  BRICKS 
IN  TWO  LAYERS 

D  =  150  mm  THICK/CONSOLIDATED  EARTH 

Fig.  3  Typical  Arrangement  in  Cement  Godown 


In  case  cement  is  received  in  drums,  these  shall  be 
stored  on  plane  level  ground,  as  far  as  possible  near 
the  concrete  mixing  place.  After  taking  out  the  required 
quantity  of  cement,  the  lid  of  the  drum  shall  be  securely 
tied  to  prevent  ingress  of  moisture. 

In  case  cement  is  received  in  silos,  the  silos  shall  be 
placed  near  the  concrete  batching  plant.  Proper  access 
shall  be  provided  for  the  replacement  of  silos. 

Different  types  of  cements  shall  be  stacked  and  stored 
separately. 

b)  Handling  —  Hooks  shall  not  be  used  for  handling 


cement  bags  unless  specifically  permitted  by  the 
engineer-in-charge.  Bags  shall  be  removed  uniformly 
from  the  top  of  the  piles  to  avoid  tipping  of  the  stack. 

For  information  regarding  bulk  handling  of  cement 

(see  8.2.4). 

8.2.3  Lime 

8.2.3. 1  Quicklime  before  slaking 

a)  Storage  and  stacking — Quicklime  should  be 
slaked  as  soon  as  possible.  If  unavoidable  it 
may  be  stored  in  compact  heaps  having  only 
the  minimum  of  exposed  area.  The  heaps  shall 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


25 


be  stored  on  a  suitable  platform  and  covered 
to  avoid  direct  contact  with  rain  or  being 
blown  away  by  wind.  In  case  quick  lime  is 
stored  in  a  covered  shed,  a  minimum  space  of 
300  mm  should  be  provided  all-round  the 
heaps  to  avoid  bulging  of  walls. 

Unslaked  lime  shall  be  stored  in  a  place 
inaccessible  to  water  and  because  of  fire 
hazards,  shall  be  segregated  from  the 
combustible  materials. 

b)  Handling  —  See  8.2.4. 

8.2.3. 2  Hydrated  lime 

a)  Storage  and  stacking  —  Hydrated  lime  is 
generally  supplied  in  containers,  such  as  jute 
bags  lined  with  polyethylene  or  craft  paper 
bags.  It  should  be  stored  in  a  building  to 
protect  the  lime  from  dampness  and  to 
minimise  warehouse  deterioration. 

The  building  should  be  with  a  concrete  floor 
and  having  least  ventilation  to  eliminate 
draughts  through  the  walls  and  roof.  In 
general,  the  recommendations  given  in  8.2.2 
for  storing  of  cement  shall  be  applicable  for 
hydrated  lime.  When  air  movement  is  reduced 
to  a  practical  minimum,  hydrated  lime  can  be 
stored  for  up  to  three  months  without 
appreciable  change. 

b)  Handling  —  See  8.2.4. 

8.2.3.3  Dry  slaked  lime 

a)  Storage  and  stacking  —  The  lime  shall  be 
stored  in  a  dry  and  closed  godown. 

b)  Handling  —  See  8.2.4. 

8.2.4  Handling  of  Cement  and  Lime 

Workers,  handling  bulk  cement  or  lime  shall  wear 
protective  clothing,  respirators,  and  goggles;  shall  be 
instructed  in  the  need  of  cleanliness  to  prevent 
dermatitis,  and  shall  be  provided  with  hand  cream, 
petroleum  jelly,  or  similar  preparation  for  protection 
of  exposed  skin.  Workers  handling  cement,  who  are 
continually  exposed  to  it,  shall,  in  addition  to  the  above 
be  equipped  with  hand  gloves  and  dust  mask. 

Bulk  cement  stored  in  silos  or  bins  may  fail  to  feed  to 
the  ejection  system.  When  necessary  to  enter  a  silo  or 
bin  for  any  purpose,  the  ejection  system  employed  shall 
be  shut  down  and  locked  out  electrically  as  well  as 
mechanically.  When  necessary  for  a  workman  to  enter 
such  storage  area,  he  shall  wear  a  life-line,  with  another 
workman  outside  the  silo  or  hopper  attending  the  rope. 

8.2.5  Masonry  Units 

a)  Stones  —  Stones  of  different  sizes,  types  and 

26 


classification  shall  be  stored  separately.  Stones 
shall  be  stacked  on  dry  firm  ground  in  a  regular 
heap  not  more  than  1  m  in  height.  Veneering 
stones  shall  be  stacked  against  vertical  support 
on  a  firm  dry  ground  in  tiers,  upto  a  height  of 
1.2  m.  A  distance  of  about  0.8  m  shall  be  kept 
between  two  adjacent  stacks. 

b)  Bricks  —  Bricks  shall  be  stacked  in  regular 
tiers  as  and  when  they  are  unloaded  to 
minimise  breakage  and  defacement.  These 
shall  not  be  dumped  at  site.  In  the  case  of 
bricks  made  from  clays  containing  lime 
Kankar,  the  bricks  in  stack  should  be 
thoroughly  soaked  in  water  (docked)  to 
prevent  lime  bursting. 

Bricks  shall  be  stacked  on  dry  firm  ground. 
For  proper  inspection  of  quality  and  ease  in 
counting,  the  stacks  shall  be  50  bricks  long, 
10  bricks  high  and  not  more  than  4  bricks  in 
width,  the  bricks  being  placed  on  edge,  two  at 
a  time  along  the  width  of  the  stack.  Clear 
distance  between  adjacent  stacks  shall  not  be 
less  than  0.8  m.  Bricks  of  each  truck  load  shall 
be  put  in  one  stack.  Bricks  of  different  types, 
such  as,  clay  bricks,  clay  fly  ash  bricks,  fly 
ash  lime  bricks,  sand  lime  (calcium  silicate) 
bricks  shall  be  stacked  separately.  Bricks  of 
different  classifications  from  strength 
consideration  and  size  consideration  (such  as, 
conventional  and  modular)  shall  be  stacked 
separately.  Also  bricks  of  different  types,  such 
as,  solid,  hollow  and  perforated  shall  be 
stacked  separately. 

c)  Blocks  —  Blocks  are  available  as  hollow  and 
solid  concrete  blocks,  hollow  and  solid  light 
weight  concrete  blocks,  autoclaved  aerated 
concrete  blocks,  concrete  stone  masonry 
blocks  and  soil  based  blocks.  Blocks  shall  be 
unloaded  one  at  a  time  and  stacked  in  regular 
tiers  to  minimise  breakage  and  defacement. 
These  shall  not  be  dumped  at  site.  The  height 
of  the  stack  shall  not  be  more  than  1 .2  m,  the 
length  of  the  stack  shall  not  be  more  than 
3.0  m,  as  far  as  possible  and  the  width  shall 
be  of  two  or  three  blocks.  Normally  blocks 
cured  for  28  days  only  should  be  received  at 
site.  In  case  blocks  cured  for  less  than  28  days 
are  received,  these  shall  be  stacked  separately. 
All  blocks  should  be  water  cured  for  10  to  14 
days  and  air  cured  for  another  15  days;  thus 
no  blocks  with  less  than  28  days  curing  shall 
be  used  in  building  construction.  Blocks  shall 
be  placed  close  to  the  site  of  work  so  that  least 
effort  is  required  for  their  transportation.  The 
date  of  manufacture  of  the  blocks  shall  be 
suitably  marked  on  the  stacks  of  blocks 

NATIONAL  BUILDING  CODE  OF  INDIA  2016 


manufactured  at  factory  or  site. 

d)  Handling  —  Brick  stacks  shall  be  placed  close 
to  the  site  of  work  so  that  least  effort  is 
required  to  unload  and  transport  the  bricks 
again  by  loading  on  pallets  or  in  barrows. 
Unloading  of  building  bricks  or  handling  in 
any  other  way  likely  to  damage  the  comers  or 
edges  or  other  parts  of  bricks  shall  not  be 
permitted. 

8.2.6  Floors,  Wall  and  Roof  Tiles 

a)  Storage  and  stacking  —  Floor,  wall  and  clay 
roof  tiles  of  different  types,  such  as,  cement 
concrete  tiles  (plain,  coloured  and  terrazzo) 
and  ceramic  tiles  (glazed  and  unglazed)  shall 
be  stacked  on  regular  platform  as  far  as 
possible  under  cover  in  proper  layers  and  in 
tiers  and  they  shall  not  be  dumped  in  heaps. 
In  the  stack,  the  tiles  shall  be  so  placed  that 
the  mould  surface  of  one  faces  that  of  another. 
Height  of  the  stack  shall  not  be  more  than  one 
metre. 

Tiles  of  different  quality,  size  and  thickness 
shall  be  stacked  separately  to  facilitate  easy 
removal  for  use  in  work.  Tiles  when  supplied 
by  manufacturers  packed  in  wooden  crates 
shall  be  stored  in  crates.  The  crates  shall  be 
opened  one  at  a  time  as  and  when  required 
for  use. 

b)  Handling  —  Ceramic  tiles  and  roof  tiles  are 
generally  supplied  in  cartons  which  shall  be 
handled  with  care  to  avoid  breakage.  It  is 
preferable  to  transport  these  at  the  site  on 
platform  trolleys. 


a)  Storage  and  stacking  —  Aggregates  shall  be 
stored  at  site  on  a  hard  dry  and  level  patch  of 
ground.  If  such  a  surface  is  not  available,  a 
platform  of  planks  or  old  corrugated  iron 
sheets,  or  a  floor  of  bricks,  or  a  thin  layer  of 
lean  concrete  shall  be  made  so  as  to  prevent 
the  mixing  with  clay,  dust,  vegetable  and  other 
foreign  matter. 

Stacks  of  fine  and  coarse  aggregate  shall  be 
kept  in  separate  stock  piles  sufficiently 
removed  from  each  other  to  prevent  the 
material  at  the  edges  of  the  piles  from  getting 
intermixed.  On  a  large  job  it  is  desirable  to 
construct  dividing  walls  to  give  each  type  of 
aggregates  its  own  compartment.  Fine 
aggregates  shall  be  stacked  in  a  place  where 
loss  due  to  the  effect  of  wind  is  minimum. 

b)  Handling  —  When  withdrawals  are  made 
from  stock  piles,  no  overhang  shall  be 
permitted. 


Employees  required  to  enter  hoppers  shall  be 
equipped  with  safety  belts  and  life-lines, 
attended  by  another  person.  Machine  driven 
hoppers,  feeders,  and  loaders  shall  be  locked 
in  the  off  position  prior  to  entry,  electrically 
as  well  as  mechanically. 

8.2.8  Pulverized  Fuel  Ash/Fly  Ash/Silica 

a)  Storage  and  stacking  —  Fly  ash/Silica  fume 
shall  be  stored  in  such  a  manner  as  to  permit 
easy  access  for  proper  inspection  and 
identification  of  each  consignment.  Fly  ash  in 
bulk  quantities  shall  be  stored  in  stack  similar 
to  fine  aggregates,  avoiding  any  intrusion  of 
foreign  matter.  Fly  ash  in  bags  shall  be  stored 
in  stacks  not  more  than  10  bags  high.  Silica 
fume,  in  general,  shall  be  stored  similar  to 
cement/fly  ash  storage  depending  upon  the 
storage  requirements  in  bags/bulk  form. 

b)  Handling — See  8.2.4. 

8.2.9  Cinder 

Cinder  shall  be  stored  in  bulk  quantities  in  stacks  similar 
to  coarse  aggregates  avoiding  any  extrusion  of  foreign 
matter. 

8.2.10  Timber 

a)  Storage  and  stacking  —  Timber  shall  be 
stored  in  stacks  upon  well  treated  and  even 
surfaced  beams,  sleepers  or  brick  pillars  so 
as  to  be  above  the  ground  level  by  at  least 
150  mm  to  ensure  that  the  timber  will  not  be 
affected  by  accumulation  of  water  under  it. 
Various  members  shall  preferably  be  stored 
separately  in  different  lengths,  and  material 
of  equal  lengths  shall  be  piled  together  in 
layers  with  wooden  battens,  called  crossers, 
separating  one  layer  from  another.  The 
crossers  shall  be  of  sound  wood,  straight  and 
uniform  in  thickness.  In  case,  where  separate 
crossers  are  not  available  smaller  sections  of 
the  available  structural  timber  may  be 
employed  in  their  place.  In  any  layer  an  air 
space  of  about  25  mm  shall  be  provided 
between  adjacent  members.  The  longer  pieces 
shall  be  placed  in  the  bottom  layers  and  shorter 
pieces  in  the  top  layers  but  one  end  of  the  stack 
shall  be  in  true  vertical  alignment.  The  crossers 
in  different  layers  shall  be  in  vertical 
alignment.  The  most  suitable  width  and  height 
of  a  stack  are  recommended  to  be  about  1.5  m 
and  2.0  m.  Distance  between  adjacent  stacks 
is  recommended  to  be  at  least  450  mm.  In  case 
the  stacking  with  the  help  of  battens  is  not 
possible,  the  timber  may  be  close  piled  in 
heaps  on  raised  foundations  with  the 


8.2.7  Aggregate 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


27 


precautions  specified  above. 

The  stacks  shall  be  protected  from  hot  dry 
winds  or  direct  sun  and  rain.  Heavy  weights, 
such  as  metal  rails  or  large  sections  of  wood, 
are  recommended  to  be  placed  on  the  top  of 
the  stack  to  prevent  distortion  or  warping  of 
the  timber  in  the  stack.  In  case  timber  is  to  be 
stored  for  about  a  year  or  more,  to  prevent  end¬ 
cracking  in  the  material,  the  ends  of  all  members 
shall  be  coated  with  coal  tar,  aluminium  leaf 
paints  (hardened  gloss  oil),  microcrystalline 
wax  or  any  other  suitable  material. 

b)  Care  must  be  taken  that  handler  or  workers 
are  not  injured  by  rails,  straps,  etc,  attached 
to  the  used  timber.  This  applies  particularly 
to  planks  and  formwork  for  shuttering. 

8.2.11  Bamboo 

8.2.11.1  The  site  shall  be  properly  inspected  and  termite 
colonies  or  mounds,  if  detected,  shall  be  destroyed. 

All  refuse  and  useless  cellulosic  materials  shall  be 
removed  from  the  site.  The  ground  may  then  be 
disinfected  by  suitable  insecticides.  The  area  should 
have  good  drainage. 

8.2.11.2  Bamboo  may  preferably  be  stacked  on  high 
skids  or  raised  platform  at  least  300  mm  above  ground. 
Storage  under  cover  reduces  the  liability  to  fungal 
attack.  Good  ventilation  and  frequent  inspection  are 
important. 

8.2.11.3  Bamboo  dries  by  air-seasoning  under  cover 
in  the  storage  yards  from  6  to  12  weeks’  time. 

8.2.11.4  Prophylactic  treatment  of  bamboo  during 
storage  prevents  losses  due  to  fungi  and  insects  even 
under  open  storage.  Following  chemicals  have  been 
found  suitable  at  a  coverage  rate  of  24  litre  per  tonne: 

a)  Sodium  pentachlorophenate  :  1  percent 
solution. 

b)  Boric  acid  +  borax  (1:1)  :  2  percent  solution. 

c)  Sodium  pentachlorophenate  :  2.5  percent 
solution  +  boric  acid  +  borax  (5:1:1). 

A  mixture  of  these  compounds  yields  the  best  results. 

NOTE  —  For  better  protection  of  structural  bamboo  (if  stored 
outside),  repetition  of  the  treatment  after  four  to  six  months  is 
desirable. 

8.2.12  Partially  Prefabricated  Wall  and  Roof 
Components 

a)  Storage  and  stacking — The  wall  components 
comprise  blocks,  sills,  lintels,  etc.  The  blocks 
shall  be  stacked  in  accordance  with  8.2.5  (c). 
These  shall  be  stacked  on  plane  level  ground 
having  a  floor  of  bricks  or  a  thin  layer  of  lean 
concrete. 


The  roof  components  such  as  precast  RC 
joists,  prefabricated  brick  panels,  RC  planks, 
channel  units,  cored  units,  waffle  units, 
L-panel,  single  tee  and  double  tee  sections, 
ferrocement  panels,  etc  shall  be  unloaded  as 
individual  components.  These  shall  be  stacked 
on  plane  level  ground  having  a  floor  of  bricks 
or  a  thin  layer  of  lean  concrete.  RC  planks, 
prefabricated  brick  panels  and  ferrocement 
panels  shall  be  stacked  against  a  brick  masonry 
wall  in  slightly  inclined  position  on  both  sides 
of  the  wall.  Channel  units,  cored  units  and 
L-panels  shall  be  stacked  one  over  the  other 
up  to  five  tiers.  The  waffle  units  shall  be 
stacked  upside  down  as  individual  units.  The 
RC  joists,  single  tee  and  double  tee  sections 
shall  be  stacked  as  individual  units  one 
adjacent  to  the  other.  The  distance  between 
any  two  adjacent  stacks  shall  not  be  less  than 
450  mm. 

b)  Handling — The  components  shall  be  handled 
by  holding  the  individual  components  at 
specified  points  so  that  the  stresses  due  to 
handling  are  minimised. 

8.2.13  Steel 

a)  Storage  and  stacking  —  For  each 
classification  of  steel,  separate  areas  shall  be 
earmarked.  It  is  desirable  that  ends  of  bars  and 
sections  of  each  class  be  painted  in  distinct 
separate  colours.  Steel  reinforcement  shall  be 
stored  in  a  way  as  to  prevent  distortion  and 
corrosion.  It  is  desirable  to  coat  reinforcement 
with  cement  wash  before  stacking  to  prevent 
scaling  and  rusting. 

Bars  of  different  classification,  sizes  and 
lengths  shall  be  stored  separately  to  facilitate 
issues  in  such  sizes  and  lengths  as  to  minimise 
wastage  in  cut  from  standard  lengths. 

In  case  of  long  storage  or  in  coastal  areas, 
reinforcement  bars  shall  be  stacked  above 
ground  level  by  at  least  150  mm  and  a  coat  of 
cement  wash  shall  be  given  to  prevent  scaling 
and  rusting. 

Structural  steel  of  different  sections,  sizes  and 
lengths  shall  be  stored  separately.  It  shall  be 
stored  above  ground  level  by  at  least  150  mm 
upon  platforms,  skids  or  any  other  suitable 
supports  to  avoid  distortion  of  sections.  In  case 
of  coastal  areas  or  in  case  of  long  storage, 
suitable  protective  coating  of  cement  wash 
shall  be  given  to  prevent  scaling  and  rusting. 

b)  Handling  —  Tag  lines  shall  be  used  to  control 
the  load  in  handling  reinforcements  or 
structural  steel  when  a  crane  is  employed. 


28 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Heavy  steel  sections  and  bundles  shall  be 
lifted  and  carried  with  the  help  of  slings  and 
tackles  and  shall  not  be  carried  on  the 
shoulders  of  the  workers. 

8.2.14  Aluminium  Sections 

a)  Storage  and  stacking  —  Aluminium  sections 
of  different  classification,  sizes  and  lengths 
shall  be  stored  separately,  on  a  level  platform 
under  cover. 

b)  Handling — The  aluminium  sections  shall  not 
be  pulled  or  pushed  from  the  stack  nor  shall 
be  slid  over  each  other,  to  protect  the 
anodizing  layer. 

8.2.15  Doors,  Windows  and  Ventilators 

a)  Storage  and  stacking  —  Metal  and  plastic 
doors,  windows  and  ventilators  shall  be 
stacked  upright  (on  their  sills)  on  level  ground 
preferably  on  wooden  battens  and  shall  not 
come  in  contact  with  dirt  or  ashes.  If  received 
in  crates  they  shall  be  stacked  according  to 
manufacturer’s  instructions  and  removed  from 
the  crates  as  and  when  required  for  the  work. 
Metal  and  plastic  frames  of  doors,  windows 
and  ventilators  shall  be  stacked  upside  down 
with  the  kick  plates  at  the  top.  These  shall  not 
be  allowed  to  stand  for  long  in  this  manner 
before  being  fixed  so  as  to  avoid  the  door 
frames  getting  out  of  shape  and  hinges  being 
strained  and  shutters  drooping. 

During  the  period  of  storage  of  aluminium 
doors,  windows  and  ventilators,  these  shall  be 
protected  from  loose  cement  and  mortar  by 
suitable  covering,  such  as  tarpaulin.  The 
tarpaulin  shall  be  hung  loosely  on  temporary 
framing  to  permit  circulation  of  air  to  prevent 
moisture  condensation. 

All  timber  and  other  lignocellulosic  material 
based  frames  and  shutters  shall  be  stored  in  a 
dry  and  clean  covered  space  away  from  any 
infestation  and  dampness.  The  storage  shall 
preferably  be  in  well-ventilated  dry  rooms. 
The  storage  shall  preferably  be  in  well- 
ventilated  dry  rooms.  The  frames  shall  be 
stacked  one  over  the  other  in  vertical  stacks 
with  cross  battens  at  regular  distances  to  keep 
the  stack  vertical  and  straight.  These  cross 
battens  should  be  of  uniform  thickness  and 
placed  vertically  one  above  the  other.  The  door 
shutters  shall  be  stacked  in  the  form  of  clean 
vertical  stacks  one  over  the  other  and  at  least 
80  mm  above  ground  on  pallets  or  suitable 
beams  or  rafters.  The  top  of  the  stack  shall  be 


covered  by  a  protecting  cover  and  weighted 
down  by  means  of  scantlings  or  other  suitable 
weights.  The  shutter  stack  shall  rest  on  hard 
and  level  surface. 

If  any  timber  or  other  lignocellulosic  material 
based  frame  or  shutter  becomes  wet  during 
transit,  it  shall  be  kept  separate  from  the 
undamaged  material.  The  wet  material  may 
be  dried  by  stacking  in  shade  with  battens  in 
between  adjacent  boards  with  free  access  of 
dry  air.  Separate  stacks  shall  be  built  up  for 
each  size,  each  grade  and  each  type  of 
material.  When  materials  of  different  sizes, 
grades  and  types  are  to  be  stacked  in  one  stack 
due  to  shortage  of  space,  the  bigger  size  shall 
be  stacked  in  the  lower  portion  of  the  stacks. 
Suitable  pallets  or  separating  battens  shall  be 
kept  in  between  the  two  types  of  material. 
Precast  concrete  door  and  window  frames 
shall  be  stored  in  upright  position  adopting 
suitable  measures  against  risk  of  subsidence 
of  soil/support. 

b)  Handling  —  While  unloading,  shifting, 
handling  and  stacking  timber  or  other 
lignocellulosic  material  based,  metal  and 
plastic  door  and  window  frames  and  shutters, 
care  shall  be  taken  that  the  pieces  are  not 
dragged  one  over  the  other  as  it  may  cause 
damage  to  their  surface  particularly  in  case  of 
the  decorative  shutters.  The  pieces  should  be 
lifted  and  carried  preferably  flat  avoiding 
damage  to  comers  or  sides. 

8.2.16  Roofing  Materials 

8.2.16.1  Roofing  sheets  shall  be  stored  and  stacked  in 

such  a  manner  as  not  to  damage  them  in  any  way. 

8.2.16.2  Asbestos  cement  sheet 

a)  Storage  and  stacking  —  Asbestos  cement 
sheets  shall  be  stacked  horizontally  to  a  height 
of  not  more  than  1  m  on  a  firm  and  level 
ground,  with  timber  or  other  packing  beneath 
them.  If  stacked  in  exposed  position,  they  shall 
be  protected  from  damage  by  wind.  Asbestos 
cement  sheets  of  same  variety  and  size  shall 
be  stacked  together.  Damaged  sheets  shall  not 
be  stacked  with  sound  materials.  All  damaged 
sheets  shall  be  salvaged  as  early  as  possible. 

b)  Handling  —  Not  more  than  two  sheets  shall 
be  first  pushed  forward  along  the  valley  line 
say  about  one  fourth  of  the  sheet  length  and 
preferably  carried  by  two  workers.  Asbestos 
cement  sheets  shall  be  lowered  or  raised  gently 
and  not  thrown. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


29 


8.2.16.3  Corrugated  galvanized  iron  sheets  and 
aluminium  sheets 

a)  Storage  and  stacking  —  Corrugated 
galvanized  iron  sheets  and  aluminium  sheets 
shall  be  stacked  horizontally  to  a  height  of  not 
more  than  0.5  m  on  a  firm  and  level  ground, 
with  timber  or  other  packing  beneath  them. 
To  protect  them  from  dust  and  rain  water,  these 
shall  be  covered  with  tarpaulin  or  polyethylene 
sheets. 

b)  Handling  —  In  bulk  handling  of  CGI  sheets, 
workers  shall  be  provided  with  suitable  hand 
protection. 

8.2.16.4  Plastic  sheets  and  glass  reinforced  plastic 
(GRP)  sheets 

a)  Storage  and  stacking  —  Plastic  sheets  and 
glass  reinforced  plastic  (GRP)  sheets  shall  be 
stacked  under  a  shed  to  a  height  of  not  more 
than  0.5  m  on  a  firm  and  level  ground  with 
timber  or  other  packing  beneath  them. 

b)  Handling  —  Handling  shall  be  done  to  avoid 
any  damage  to  the  sheets. 

8.2.17  Boards 

8.2.17.1  Gypsum  boards 

a)  Storage  and  stacking — Gypsum  boards  shall 
be  stored  flat  in  a  covered  clean  and  dry  place. 

b)  Handling  —  See  8.2.17.2  (b). 

8.2.17.2  Plywood,  fibre  board,  particle  board,  block 
board,  etc 

a)  Storage  and  stacking — Plywood,  fibre  board, 
particle  board,  block  board,  etc,  shall  not  be 
stored  in  the  open  and  exposed  to  direct  sun 
and  rain.  The  boards  shall  be  stacked  on  a  flat 
dunnage,  on  the  top  of  which  a  wooden  frame 
shall  be  constructed  with  battens  of 
50  mm  x  25  mm  (Min)  in  such  a  way  that  it 
supports  all  four  edges  and  corners  of  the 
boards  with  intermediate  battens  placed  at 
suitable  intervals  to  avoid  warping.  If  required, 
the  stack  shall  be  adequately  raised  above 
ground  level  to  ensure  that  it  will  not  be 
affected  by  accumulation  of  water  under  it. 
The  board  shall  be  stacked  in  a  solid  block  in 
a  clear  vertical  alignment.  The  top  sheet  of 
each  stack  shall  be  suitably  weighed  down  to 
prevent  warping,  wherever  necessary. 

b)  Handling  —  The  board  shall  be  unloaded  and 
stacked  with  utmost  care  avoiding  damage  to 
the  comers  and  surface.  In  case  of  decorative 
plywood  and  decorative  boards,  the  surfaces 


of  which  are  likely  to  get  damaged  by  dragging 
one  sheet  over  another,  it  is  advisable  that 
these  are  lifted  as  far  as  possible  in  pairs  facing 
each  other. 

8.2.18  Plastic  and  Rubber  Flooring  Sheets  and  Tiles 

a)  Storage  and  stacking  —  Plastic  and  rubber 
sheets  have  tendency  to  break-down  during 
storage.  Plastic  and  rubber  sheets  shall  be 
stored  according  to  manufacturer’s 
instructions. 

The  coolest  store  room  available  shall  be 
utilized  for  the  storage  of  the  sheets.  The  store 
rooms  where  the  sheets  are  stored  shall  be  well 
ventilated  and  direct  light  should  not  be 
allowed  to  fall  on  them. 

The  sheets  shall  be  stored  away  from  electric 
generators,  electric  motors,  switchgears  and 
other  such  electrical  equipment  as  they 
produce  harmful  odour/gases. 

Contamination  of  the  sheets  with  vegetable 
and  mineral  oils;  greases;  organic  solvents; 
acids  and  their  fumes;  alkalies;  dust  and  grit 
shall  be  prevented.  Where  greasy 
contamination  occurs,  this  shall  be  removed 
immediately  with  petrol  and  the  sheets  and 
tiles  thoroughly  wiped  dry  and  dusted  with 
chalk. 

Undue  stretch  and  strain,  kinks,  sharp  bends 
or  folds  of  the  sheets  and  tiles  shall  be  avoided. 
In  case  of  long  storage,  the  sheets  shall  be 
turned  over  periodically  and  treated  with  chalk 
powder,  if  necessary. 

b)  Handling  —  While  handling  plastic  and 
rubber  sheets,  workers  shall  lift  the  sheets  and 
carry  them  flat  to  avoid  sharp  bends  or  folds 
of  the  sheets. 

8.2.19  Glass  Sheets 

a)  Storage  and  stacking  —  The  special  glasses 
shall  be  stored  and  handled  as  per 
manufacturer’s  instructions.  It  is  important 
that  all  glass  sheets  whether  stored  in  crates 
or  not  shall  be  kept  dry.  Suitable  covered 
storage  space  shall  be  provided  for  the  safe 
storage  of  the  glass  sheets.  The  glass  sheets 
shall  be  lifted  and  stored  on  their  long  edges 
and  shall  be  put  into  stacks  of  not  more  than 
25  panes,  supported  at  two  points  by  fillets  of 
wood  at  about  300  mm  from  each  end.  The 
first  pane  laid  in  each  stack  shall  be  so  placed 
that  its  bottom  edge  is  about  25  mm  from  the 
base  of  the  wall  or  other  support  against  which 
the  stack  rests.  The  whole  stack  shall  be  as 
close  and  as  upright  as  possible.  To  prevent 


30 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


slipping  on  smooth  floor,  the  floor  shall  be 
covered  with  gunny  bags.  The  glass  sheets  of 
different  sizes,  thickness  and  type  shall  be 
stacked  separately.  The  distance  between  any 
two  stacks  shall  be  of  the  order  of  400  mm. 

b)  Handling  —  Workers  handling  glass  panes, 
waste  glass  pieces  and  fibre  glass  shall  be 
provided  with  suitable  hand  protection.  In 
removing  glass  sheets  from  crates,  due  care 
shall  be  taken  to  avoid  damages.  Glass  edges 
shall  be  covered  or  otherwise  protected  to 
prevent  injuries  to  workers.  Special  glasses 
shall  be  stored  and  handled  as  per 
manufacturer’s  instructions. 

8.2.20  Cast  Iron,  Galvanized  Iron  and  Asbestos  Cement 

Pipes  and  Fittings 

a)  Storage  and  stacking  —  The  pipes  shall  be 
unloaded  where  they  are  required,  when  the 
trenches  are  ready  to  receive  them. 

Storage  shall  be  provided  at  the  bottom  layer 
to  keep  the  stack  stable.  The  stack  shall  be  in 
pyramid  shape  or  the  pipes  placed  lengthwise 
and  crosswise  in  alternate  layers.  The  pyramid 
stack  is  advisable  in  smaller  diameter  pipes 
for  conserving  space  in  storing  them.  The 
height  of  the  stack  shall  not  exceed  1.5  m. 
Each  stack  shall  contain  only  pipes  of  same 
class  and  size,  with  consignment  or  batch 
number  marked  on  it  with  particulars  or 
suppliers  wherever  possible. 

Cast  iron  detachable  joints  and  fittings  shall 
be  stacked  under  cover  and  separated  from 
the  asbestos  cement  pipes  and  fittings. 
Rubber  rings  shall  be  kept  clean,  away  from 
grease,  oil,  heat  and  light. 

b)  Handling  —  Pipes  in  the  top  layer  shall  be 
handled  first.  At  a  time  only  one  pipe  shall  be 
handled  by  two  labourers  while  carrying  to 
the  actual  site  and  shall  be  carried  on 
shoulders.  Fittings  shall  be  handled 
individually. 

8.2.21  Polyethylene  Pipes 

a)  Storage  and  stacking  —  Black  polyethylene 
pipes  may  be  stored  either  under  cover  or  in 
the  open.  Natural  polyethylene  pipes, 
however,  should  be  stored  under  cover  and 
protected  from  direct  sunlight. 

Coils  may  be  stored  either  on  edge  or  stacked 
flat  one  on  top  of  the  other,  but  in  either  case 
they  should  not  be  allowed  to  come  into 
contact  with  hot  water  or  steam  pipes  and 
should  be  kept  away  from  hot  surface. 
Straight  lengths  should  be  stored  on  horizontal 


racks  giving  continuous  support  to  prevent  the 
pipe  taking  on  a  permanent  set.  Storage  of 
pipes  in  heated  areas  exceeding  27°C  should 
be  avoided. 

b)  Handling — Removal  of  pipe  from  a  pile  shall 
be  accomplished  by  working  from  the  ends  of 
the  pipe. 

8.2.22  Unplasticized  PVC  Pipes 

a)  Storage  and  stacking  —  Pipes  should  be 
stored  on  a  reasonably  flat  surface  free  from 
stones  and  sharp  projections  so  that  the  pipe 
is  supported  throughout  its  length.  The  pipe 
should  be  given  adequate  support  at  all  times. 
In  storage,  pipe  racks  should  be  avoided.  Pipe 
should  not  be  stacked  in  large  piles  especially 
under  warm  temperature  conditions  as  the 
bottom  pipes  may  distort  thus  giving  rise  to 
difficulty  in  jointing.  Socket  and  spigot  pipes 
should  be  stacked  in  layers  with  sockets  placed 
at  alternate  ends  of  the  stacks  to  avoid  lopsided 
stacks. 

It  is  recommended  not  to  store  a  pipe  inside 
another  pipe.  On  no  account  should  pipes  be 
stored  in  a  stressed  or  bend  condition  or  near 
a  source  of  heat.  Pipes  should  not  be  stacked 
more  than  1.5  m  high.  Pipes  of  different  sizes 
and  classes  should  be  stacked  separately. 

In  tropical  conditions,  pipes  should  be  stored 
in  shade.  In  very  cold  weather,  the  impact 
strength  of  PVC  is  reduced  making  it  brittle. 
The  ends  of  pipe  should  be  protected  from 
abrasion  particularly  those  specially  prepared 
for  jointing  either  spigot  or  socket  solvent 
welded  joints  or  soldered  for  use  with 
couplings. 

If  due  to  unsatisfactory  storage  or  handling,  a 
pipe  becomes  kinked,  the  damaged  portion 
should  be  cut  out  completely.  Kinking  is  likely 
to  occur  only  on  very  thin  walled  pipes. 

b)  Handling  —  Great  care  shall  be  exercised  in 
handling  these  pipes  in  wintry  conditions  as 
these  become  brittle  in  very  cold  weather. 

8.2.23  Pipes  of  Conducting  Materials 

a)  Storage  and  stacking  —  Pipes  shall  be  stacked 
on  solid  level  sills  and  contained  in  a  manner 
to  prevent  spreading  or  rolling  of  the  pipe. 
Where  quantity  storage  is  necessary,  suitable 
packing  shall  be  placed  between  succeeding 
layers  to  reduce  the  pressure  and  resulting 
spreading  of  the  pile. 

In  stacking  and  handling  of  pipes  and  other 
conducting  materials,  the  following  minimum 
safety  distances  shall  be  ensured  from  the 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


31 


overhead  power  lines: 

1)  11  kV  and  below  :  1.40  m 

2)  Above  11  and  below  33  kV  :  3.60  m 

3)  Above  33  and  below  132  kV  :  4.70  m 

4)  Above  132  and  below  275  kV  :  5.70  m 

5)  Above  275  and  below  400  kV  :  6.50  m 
b)  Handling  —  Removal  of  pipes  from  a  pile 

shall  be  accomplished  by  working  from  the 
ends  of  the  pipe.  During  transportation,  the 
pipes  shall  be  so  secured  as  to  ensure  against 
displacement. 

8.2.24  Piles  and  Poles 

a)  Storage  and  stacking  —  Piles  and  poles  shall 
be  carefully  stacked  on  solid,  level  sills  so  as 
to  prevent  rolling  or  spreading  of  the  pile. 
The  storage  area  shall  be  maintained  free  of 
vegetation  and  flammable  materials. 

b)  Handling  —  When  placing  piles  or  poles  on 
the  stack,  workers  shall  work  from  the  ends 
of  the  piles/poles.  Similar  precautions  shall 
be  observed  in  removal  of  piles/poles  from 
the  stack.  Tag  lines  shall  be  used  to  control 
piles  and  poles  when  handling  for  any  purpose. 

In  stacking  and  handling  of  piles  and  poles,  precautions 
as  laid  down  in  8.2.18  (a)  shall  be  followed. 

8.2.25  Paints,  Varnishes  and  Thinners 

a)  Storage  and  stacking  —  Paints,  varnishes, 
lacquers,  thinners  and  other  flammable 
materials  shall  be  kept  in  properly  sealed  or 
closed  containers.  The  containers  shall  be  kept 
in  a  well  ventilated  location,  free  from 
excessive  heat,  smoke,  sparks  or  flame.  The 
floor  of  the  paint  stores  shall  be  made  up  of 
1 00  mm  thick  loose  sand. 

Paint  materials  in  quantities  other  than 
required  for  daily  use  shall  be  kept  stocked 
under  regular  storage  place. 

Where  the  paint  is  likely  to  deteriorate  with 
age,  the  manner  of  storage  shall  facilitate 
removal  and  use  of  lots  in  the  same  order  in 
which  they  are  received. 

Temporary  electrical  wirings/fittings  shall  not 
be  installed  in  the  paint  store.  When  electric 
lights,  switches  or  electrical  equipment  are 
necessary,  they  shall  be  of  explosion  proof 
design. 

b)  Handling —  Adequate  ventilation  to  prevent 
the  accumulation  of  flammable  vapours  to 
hazardous  levels  of  concentration  shall  be 
provided  in  all  areas  where  painting  is  done. 


When  painting  is  done  in  confined  spaces  where 
flammable  or  explosive  vapours  may  develop,  any 
necessary  heat  shall  be  provided  through  duct  work 
remote  from  the  source  of  flame. 

Sources  of  ignition,  such  as  open  flame  and  exposed 
heating  elements,  shall  not  be  permitted  in  area  or  rooms 
where  spray  painting  is  done  nor  shall  smoking  be 
allowed  there. 

Care  should  be  taken  not  to  use  any  naked  flame  inside 
the  paint  store.  Buckets  containing  sand  shall  be  kept 
ready  for  use  in  case  of  fire.  Fire  extinguishers  when 
required  shall  be  of  foam  type  conforming  to  accepted 
standards  [7(23)]  {see  also  good  practice  [7(24)]}. 

Each  workman  handling  lead  based  paints  shall  be 
issued  Vi  litre  milk  per  day  for  his  personal 
consumption. 

8.2.26  Bitumen,  Road  Tar,  Asphalt,  etc 

a)  Storage  and  stacking  -  Drums  or  containers 
containing  all  types  of  bitumen,  road  tar, 
asphalt,  etc,  shall  be  stacked  vertically  on  their 
bottoms  in  up  to  3  tiers.  Leaky  drums  shall  be 
segregated.  Empty  drums  shall  be  stored  in 
pyramidal  stacks  neatly  in  rows. 

b)  Handling  —  See  9.13.3.1.2  and  9.13.3.4, 

8.2.27  Bituminous  Roofing  Felts 

a)  Storage  and  stacking  —  Bituminous  roofing 
felts  shall  be  stored  away  from  other 
combustible  materials  and  shall  be  kept  under 
shade. 

b)  Handling  —  Bituminous  roofing  felts  should 
be  handled  in  a  manner  to  prevent  cracking 
and  other  damages. 

8.2.28  Flammable  Materials 

a)  Storage  and  stacking  —  In  addition  to  the 
requirements  as  laid  down  in  8.1.3,  the 
following  provisions  shall  also  apply: 

1)  Outdoor  storage  of  drums  requires  some 
care  to  avoid  contamination  because 
moisture  and  dirt  in  hydraulic  brake  and 
transmission  fluid,  gasoline,  or  lubricants 
may  cause  malfunction  or  failure  of 
equipment,  with  possible  danger  to 
personnel.  The  storage  area  should  be  free 
of  accumulations  of  spilled  products, 
debris  and  other  hazards. 

2)  Compressed  gases  and  petroleum 
products  shall  not  be  stored  in  the  same 
building  or  close  to  each  other.  Storage 
of  petroleum  products  should  be  as  per 
Petroleum  Rules,  2002,  as  amended  from 
time-to-time. 


32 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


b)  Handling  —  Petroleum  products  delivered  to 
the  job  site  and  stored  there  in  drums  shall  be 
protected  during  handling  to  prevent  loss  of 
identification  through  damage  to  drum 
markings,  tags,  etc.  Unidentifiable  petroleum 
products  may  result  in  improper  use,  with 
possible  fire  hazard,  damage  to  equipment  or 
operating  failure. 

Workers  shall  be  required  to  guard  carefully  against 
any  part  of  their  clothing  becoming  contaminated  with 
flammable  fluids.  They  shall  not  be  allowed  to  continue 
work  when  their  clothing  becomes  so  contaminated. 

8.2.29  Water 

Water  to  be  stored  for  construction  purposes  shall  be 
stored  in  proper  tanks  to  prevent  any  ingress  of  organic 
impurities.  The  aggregate  capacity  of  storage  tanks  shall 
be  determined  after  taking  into  account  the 
requirements  of  firefighting. 

8.2.30  Sanitary  Appliances 

a)  Storage  and  stacking  —  All  sanitary 
appliances  shall  be  carefully  stored  under 
cover  to  prevent  damage.  When  accepting  and 
storing  appliances,  consideration  shall  be 
given  to  the  sequence  of  removal  from  the 
store  to  the  assembly  positions.  Vitreous 
fittings  shall  be  stacked  separately  from  the 
metal  ones. 

b)  Handling  —  Bigger  sanitary  appliances  shall 
be  handled  one  at  a  time.  Traps,  water  seals 
and  gullies  shall  be  handled  separately.  While 
handling  sanitary  fittings  they  shall  be  free 
from  any  oil  spilling,  etc.  The  hands  of  the 
workers  shall  also  be  free  from  any  oily 
substance.  Before  lowering  the  appliances  in 
their  position  the  supporting  brackets, 
pedestals,  etc,  shall  be  checked  for  their 
soundness  and  then  only  the  fixtures  be 
attached. 

8.2.31  Other  Materials 

Polymeric  materials  such  as  coatings,  sheeting, 
reflective  surfacing/sheeting,  etc,  shall  be  stored  as  per 
the  manufacturers’  instructions.  Special  precautions 
shall  be  taken  in  case  of  storage,  handling  and  usage  of 
toxic  materials. 

Small  articles  like  screws,  bolts,  nuts,  door  and  window 
fittings,  polishing  stones,  protective  clothing,  spare 
parts  of  machinery,  linings,  packings,  water  supply  and 
sanitary  fittings,  and  electrical  fittings,  insulation  board, 
etc,  shall  be  kept  in  suitable  and  properly  protected 
containers  or  store  rooms.  Valuable  small  materials  shall 
be  kept  under  lock  and  key. 


8.2.32  Special  Considerations 

8.2.32.1  Materials  constantly  in  use  shall  be  relatively 
nearer  to  the  place  of  use. 

8.2.32.2  Heavy  units  like  precast  concrete  members 
shall  be  stacked  near  the  hoist  or  the  ramp. 

8.2.32.3  Materials  which  normally  deteriorate  during 
storage  shall  be  kept  constantly  moving,  by  replacing 
old  materials  with  fresh  stocks.  Freshly  arrived 
materials  shall  never  be  placed  over  materials  which 
had  arrived  earlier. 

8.2.32.4  Appropriate  types  of  fire  extinguishers  shall 
be  provided  at  open  sites  where  combustible  materials 
are  stored  and  for  each  storage  shed/room  where 
flammable/combustible  materials  are  stored.  For 
guidance  regarding  selection  of  the  appropriate  types 
of  fire  extinguishers  reference  may  be  made  to  good 
practice  [7(24)].  It  is  desirable  that  a  minimum  of  two 
extinguishers  are  provided  at  each  such  location. 

8.2.32.5  Workers  handling  excavated  earth  from 
foundation,  particularly  if  the  site  happens  to  be 
reclaimed  area  or  marshy  area  or  any  other  infected 
area,  shall  be  protected  against  infection  affecting  their 
exposed  body  portions. 

8.2.32.6  House  keeping 

Stairways,  walkways,  scaffolds,  and  access  ways  shall 
be  kept  free  of  materials,  debris  and  obstructions.  The 
engineer-in-charge/the  foreman  shall  initiate  and  carry 
out  a  programme  requiring  routine  removal  of  scrap 
and  debris  from  scaffolds  and  walkways. 

8.2.32.7  Where  stacking  of  the  materials  is  to  be  done 
on  road  side  berms  in  the  street  and  other  public  place, 
the  owner  shall  seek  permission  from  the  Authority  for 
such  stacking  and  also  for  removing  the  remnants  of 
the  same  after  the  construction  is  over,  so  as  to  avoid 
any  hazard  to  the  public. 

8.3  Unloading  Rail/Road  Wagons  and  Motor 
Vehicles 

8.3.1  Loading  and  unloading  from  rail/road  wagons 

8.3. 1.1  Appropriate  warning  signals  shall  be  displayed 
to  indicate  that  the  wagons  shall  not  be  coupled  or 
moved. 

8.3. 1.2  The  wheels  of  wagons  shall  always  be  sprigged 
or  chained  while  the  wagons  are  being  unloaded.  The 
brakes  alone  shall  not  be  depended  upon. 

8.3. 1.3  Special  level  bars  shall  preferably  be  used  for 
moving  rail  wagons  rather  than  ordinary  crow  bars. 

8.3. 1.4  Where  gangplanks  are  used  between  wagons 
and  platforms  of  piles  (heaps),  cleats  at  lower  end  of 


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33 


gangplank,  or  pin  through  end  of  gangplanks,  shall  be 
used  to  prevent  sliding.  If  gangplank  is  on  a  gradient, 
cleats  or  abrasive  surface  shall  be  provided  for  the  entire 
length. 

8.3. 1.5  When  rail/road  wagons  are  being  loaded  or 
unloaded  near  passageways  or  walkways,  adequate 
warning  signals  shall  be  placed  on  each  end  of  the 
wagon  to  warn  pedestrians. 

8.3.2  Loading  and  Unloading  from  Motor  Vehicles 

8.3.2. 1  The  motor  vehicles  shall  be  properly  blocked 
while  being  loaded  or  unloaded;  brakes  alone  shall  not 
be  depended  upon  to  hold  them. 

8. 3. 2. 2  When  motor  vehicles  are  being  loaded  or 
unloaded  near  passageways  or  walkways,  adequate 
warning  signs  shall  be  placed  on  each  end  of  the  vehicle 
to  warn  the  pedestrians. 

8.3. 2. 3  Adequate  lighting  shall  be  provided  while 
loading/unloading. 

8.3.3  Handling  Heavy/Long  Items 

8.3.3. 1  Loading  and  unloading  of  heavy  items,  shall, 
as  far  as  possible,  be  done  with  cranes  or  gantries.  The 
workman  shall  stand  clear  of  the  material  being  moved 
by  mechanical  equipment.  The  slings  and  the  ropes  used 
shall  be  of  adequate  load  carrying  capacity,  so  as  not 
to  give  way  and  result  in  accidents. 

8.3.3.2  While  heavy  and  long  components  are  being 
manually  loaded  into  motor  vehicle,  wagons,  trailer, 
etc,  either  wooden  sleepers  or  steel  rails  of  sufficient 
length  and  properly  secured  in  position  shall  be  put  in 
a  gentle  slope  against  the  body  of  the  wagon/vehicle  at 
3  or  4  places  for  loading.  These  long  items  shall  be 
dragged,  one  by  one,  gently  and  uniformly  along  these 
supports  by  means  of  ropes,  being  pulled  by  men  with 
feet  properly  anchored  against  firm  surface.  As  soon 
as  the  items  come  on  the  floor  of  the  vehicle,  the  same 
may  be  shifted  by  crowbars  and  other  suitable  leverage 
mechanism,  but  not  by  hands  to  avoid  causing  accident 
to  the  workers. 

8.3.3.3  Similar  procedure  as  outlined  under  8.3.3.2  shall 
be  followed  for  manual  unloading  of  long  or  heavy 
items. 

SECTION  4  SAFETY  IN  CONSTRUCTION 

9  SAFETY  IN  CONSTRUCTION  OF  ELEMENTS 
OF  A  BUILDING 

9.1  General 

9.1.1  The  provisions  of  this  section  shall  apply  to  the 
erection/alteration  of  the  various  parts  of  a  building  or 
similar  structure.  The  construction  of  the  different 
elements  shall  conform  to  6.4. 


9.1.2  Other  Laws 

Nothing  herein  stated  shall  be  construed  to  nullify  any 
rules,  regulations,  safety  standards  or  statutes  of  the 
local  state  governments  or  those  contained  in  the 
various  Acts  of  the  Government  of  India.  The  specific 
rules,  regulations  and  acts  pertaining  to  the  protection 
of  the  public  or  workers  from  health  and  other  hazards, 
wherever  specified  by  the  Local/State  Authority  or  in 
the  Acts  of  the  Government  take  precedence  over 
whatever  is  herein  specified  in  case  of  a  doubt  or 
dispute. 

9.1.3  Safety  Management 

9.1.3. 1  The  safety  of  personnel  engaged  in  building 
construction  should  be  ensured  through  a  well  planned 
and  well  organized  mechanism  by  employing  the 
guidelines  given  in  good  practice  [7(12)]. 

9.1.3.2  Notwithstanding  the  guidelines  given  in  9.1.3. 1, 
all  provisions  given  in  relevant  Act/Rules/Regulations 
as  amended  from  time  to  time  shall  be  followed;  in  this 
regard,  reference  shall  also  be  made  to  the  Building 
and  other  Construction  Workers  (Regulation  of 
Employment  and  Conditions  of  Service)  Act,  1996  and 
the  rules/regulations  framed  thereunder. 

9.2  Temporary  Construction,  Use  of  Side  Walls  and 
Temporary  Encroachments 

9.2.1  Temporary  Construction 

The  plans  and  specifications  of  temporary 
constructions,  which  are  likely  to  interfere  with  facilities 
or  right  of  way  provided  by  the  Authority,  shall  be 
submitted  to  the  Authority  for  approval  showing  clearly 
the  layout,  design  and  construction. 

9.2. 1.1  Temporary  structure  referred  to  in  9.2.1  shall 
apply  to  the  following  types  of  structures  : 

a)  Structures  with  roof  or  walls  made  of  straw, 
hay,  ulugrass,  golpatta,  hogle,  darma,  mat, 
canvas  cloth  or  other  like  materials  not 
adopted  for  permanent  or  continuous 
occupancy. 

b)  Site-work  sheds,  truck-runways,  trestles,  foot¬ 
bridges,  etc. 

9.2.2  For  detailed  information  regarding  fire  safety 
aspects  in  respect  of  construction,  location, 
maintenance  and  use  of  temporary  structures 
[mentioned  in  9.2.1.1(a)]  including  pandals  used  by 
public  for  outdoor  assembly,  reference  may  be  made 
to  good  practice  [7(25)]. 

9.2.3  Special  permits  shall  be  obtained  for  the  storage 
of  the  materials  on  side  walks  and  highways.  It  shall  be 
ensured  that  the  material  dump  or  the  storage  shed  does 
not  create  a  traffic  hazard,  nor  it  shall  interfere  with 
the  free  flow  of  the  pedestrian  traffic.  Special  permits 


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shall  also  be  obtained  for  the  use  of  water  and  electricity 
from  the  public  facilities.  Whenever  such  utilities  are 
made  use  of,  adequate  safety  precautions  regarding 
drainage  and  elimination  of  contamination  and  hazards 
from  electricity  shall  be  taken. 

9.2.4  In  order  to  ensure  safety  for  the  adjoining 
property,  adequate  temporary  protective  guards  are  to 
be  provided.  In  case  these  protective  devices  project 
beyond  the  property,  the  consent  of  the  Authority  and 
that  of  the  owner  of  the  adjoining  property  shall  be 
obtained. 

9.3  Testing 

9.3.1  Tests 

No  structure,  temporary  support,  scaffolding  or  any 
construction  equipment  during  the  construction  or 
demolition  of  any  building  or  structure  shall  be  loaded 
beyond  the  allowable  loads  and  working  stresses  as 
provided  for  in  Part  6  ‘Structural  Design’  of  the  Code 
{see  also  good  practices  [7(26)]}. 

9.3. 1.1  Whenever  any  doubt  arises  about  the  structural 
adequacy  of  a  scaffolding,  support  or  any  other 
construction  equipment,  it  shall  be  tested  to  two  and  a 
half  times  the  superimposed  dead  and  imposed  loads 
to  which  the  material  or  the  equipment  is  subjected  to 
and  the  member/material  shall  sustain  the  test  load 
without  failure  if  it  is  to  be  accepted. 

9.3.2  Notwithstanding  the  test  mentioned  above,  if  any 
distress  in  any  member  is  visible,  the  member  shall  be 
rejected. 

9.4  Inspection  and  Rectification  of  Hazardous 
Defects 

9.4.1  Inspection 

The  Authority  shall  inspect  the  construction  equipment 
and  if  during  the  inspection,  it  is  revealed  that  unsafe/ 
illegal  conditions  exist,  the  Authority  shall  intimate  the 
owner  and  direct  him  to  take  immediate  remedial 
measures  to  remove  the  hazard/violation. 

9.4.2  Rectification 

The  owner  shall  proceed  to  rectify  the  defect,  hazardous 
condition  or  violation  within  24  h  of  the  receipt  of  the 
notice  from  the  Authority.  The  Authority  shall  have  full 
powers  to  rectify  the  unsafe  condition  and  all  expenses 
incurred  in  this  connection  is  payable  by  the  owner  of 
the  property.  Illegal  encroachments  and  non-payment 
of  money  due,  in  respect  of  the  rectification  of  unsafe 
conditions  may  vest  a  lien  on  the  property  with  the 
Authority  (see  also  Part  2  ‘Administration’  of  the  Code). 

9.4.3  When  the  strength  and  adequacy  of  any  scaffold 


or  other  construction  equipment  is  in  doubt  or  when 
any  complaint  is  made,  the  Authority  shall  get  the  same 
inspected  before  use. 

9.5  Foundations 

9.5.1  General 

The  distribution  of  the  supporting  foundation  shall  be 
such  as  to  avoid  any  harmful  differential  settlement  of 
the  structure.  The  type  and  design  of  the  foundation 
adopted  shall  ensure  safety  to  workers  during 
construction  and  residents  of  the  neighbouring  property. 
Sufficient  care  shall  be  taken  in  areas,  where  withdrawal 
of  ground  water  from  surrounding  areas  could  result  in 
damages  to  such  foundations.  During  the  construction 
of  the  foundation,  it  shall  be  ensured  that  the  adjoining 
properties  are  not  affected  by  any  harmful  effects. 

9.5.2  Adjoining  Properties 

The  person  causing  excavation  shall,  before  starting 
the  work,  give  adequate  notices  in  writing  to  the  owner 
of  the  adjoining  properties,  safety  of  which  is  likely  to 
be  affected  due  to  excavation.  After  having  given  such 
notices,  wherein  details  regarding  the  type  of  protective 
works  that  are  anticipated  to  be  incorporated  in  the 
excavation  are  shown,  written  permission  shall  be 
obtained  for  such  excavation  from  the  adjoining 
property  owners.  Where  necessary,  the  person  causing 
excavation  shall  make  adequate  provision  to  protect 
the  safety  of  adjacent  property.  If  on  giving  such  notices 
and  the  precautionary  measures  having  been  approved 
by  the  Authority,  the  adjoining  property  owner  still 
refuses  to  give  necessary  facilities  to  the  person  causing 
excavation  for  protecting/providing  both  temporary  and 
permanent  supports  to  such  property,  the  responsibility 
for  any  damage  to  the  adjoining  property  shall  be  that 
of  the  adjoining  property  owner.  The  person  causing 
excavation  shall  be  absolved  of  responsibility  for  any 
loss  of  property  or  life  in  the  adjoining  property. 

9. 5. 2.1  Protection  to  neighbouring  structures  and 
adjoining  services 

In  driven  piles,  vibration  is  set  up  which  may  cause 
damage  to  adjoining  structures  or  service  lines 
depending  on  the  nature  of  soil  condition  and  the 
construction  standard  of  such  structures  and  service 
lines.  Possible  extent  of  all  such  damages  shall  be 
ascertained  in  advance  and  operation  and  mode  of 
driving  shall  be  planned  with  appropriate  measures  to 
ensure  safety. 

Wherever  in  the  vicinity  of  a  site  where  bored  or  driven 
piling  works  are  to  be  carried  out  there  are  old  structures 
which  are  likely  to  be  damaged,  tell-tales  shall  be  fixed 
on  such  structures  to  watch  their  behaviour  and  timely 
precautions  taken  against  any  undesirable  effect. 

In  case  of  bored  piles,  measures  shall  be  taken  to  ensure, 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


35 


that  there  is  no  appreciable  movement  of  soil  mass  into 
the  borehole  which  may  cause  subsidence  to  any 
existing  foundation  in  the  close  proximity.  In  wet  holes 
where  such  possibilities  are  likely  to  be  there  the  same 
shall  be  minimised  by  approved  technique  and  the 
operation  should  be  planned. 

9.5.3  During  construction,  inspection  shall  be  made  by 
the  engineer-in-charge  to  ensure  that  all  protective 
works  carried  out  to  safe-guard  the  adjoining  property 
are  sufficient  and  in  good  order  to  ensure  safety 
(see  Part  2  ‘Administration’  of  the  Code). 

9.5.4  Before  carrying  out  any  excavation  work/pile 
driving,  the  position,  depth  and  size  of  underground 
structures,  such  as  water  pipes,  mains,  cables  or  other 
services  in  the  vicinity  to  the  proposed  work,  may  be 
obtained  from  the  Authority  to  prevent  accidents  to 
workers  engaged  in  excavation  work  and  calamities  for 
the  general  public. 

Prior  to  commencement  of  excavation  detailed  data  of 
the  type  of  soils  that  are  likely  to  be  met  with  during 
excavation  shall  be  obtained  and  the  type  of  protective 
works  by  way  of  shoring  timbering,  etc,  shall  be  decided 
upon  for  the  various  strata  that  are  likely  to  be 
encountered  during  excavation.  For  detailed  information 
regarding  safety  requirements  during  excavation 
reference  may  be  made  to  good  practice  [7(20)]. 

9.6  General  Requirements  and  Common  Hazards 
During  Excavation 

9.6.1  Location  of  Machinery  and  Tools 

Excavating  machinery  consisting  of  both  heavy  and 
light  types  shall  be  kept  back  from  the  excavation  site 
at  a  distance  which  would  be  safe  for  such  type  of 
equipment.  Heavy  equipment,  such  as  excavating 
machinery  and  road  traffic  shall  be  kept  back  from  the 
excavated  sites  at  a  distance  of  not  less  than  the  depth 
of  trench  or  at  least  6  m  for  trench  deeper  than  6  m. 
Care  shall  also  be  taken  to  keep  excavating  tools  and 
materials  far  away  from  the  edge  of  trench  to  prevent 
such  items  being  inadvertently  knocked  into  the  trench. 

9.6.2  Excavated  Materials 

Excavated  materials  shall  be  kept  back  from  the  edges 
of  the  trench  to  provide  clear  berm  of  safe  width.  Where 
this  is  not  feasible,  the  protective  works  designed  for 
the  trenches  shall  take  into  consideration,  the  additional 
load  due  to  overburden  of  materials. 

9.6.2. 1  Other  surcharges 

Proximity  of  buildings,  piles  of  lumber,  crushed  rocks, 
sand  and  other  construction  materials,  large  trees,  etc, 
may  impose  surcharges  on  the  side  of  the  trench  to  cause 
sliding,  etc.  Under  these  conditions  additional 
protective  works  shall  be  provided  to  support  the  sides 
of  the  trench. 


9.6.3  Type  of  Strata 

Adequate  precautions,  depending  upon  the  type  of  strata 
met  with  during  excavation  (like  quick  sand,  loose  fills 
and  loose  boulder)  shall  be  taken  to  protect  the  workers 
during  excavation.  Effect  of  climatic  variations  and 
moisture  content  variations  on  the  materials  under 
excavation  shall  be  constantly  watched  and  precautions 
taken,  where  necessary,  immediately  to  prevent 
accidents  at  work  site. 

9.6.4  Overhang  and  Slopes 

During  any  excavation,  sufficient  slopes  to  excavated 
sides  by  way  of  provision  of  steps  or  gradual  slopes 
shall  be  provided  to  ensure  the  safety  of  men  and 
machine  working  in  the  area. 

9.6.5  Blasting  for  foundation  of  building  is  prohibited 
unless  special  permission  is  obtained  from  the 
Authority.  Where  blasting  technique  has  to  be  resorted 
to,  prior  inspection  for  the  stability  of  slopes  shall  be 
carried  out.  After  blasting,  overhangs  or  loose  boulders 
shall  be  cleared  by  expert  workers  carrying  out  blasting 
prior  to  continuation  of  the  excavation  by  normal 
working  parties. 

9. 6. 5.1  Burrowing  or  mining  or  what  is  known  as 
‘gophering’  shall  not  be  allowed.  In  any  trench  where 
such  methods  have  been  followed,  the  cavities  felt  shall 
be  eliminated  by  cutting  back  the  bare  slope  before 
removing  any  further  material  from  the  section  of  the 
trench. 

9.6.6  Health  Hazards 

Where  gases  or  fumes  are  likely  to  be  present  in 
trenches,  sufficient  mechanical  ventilation,  to  protect 
the  health  and  safety  of  persons  working  there,  shall  be 
provided.  If  necessary,  the  personnel  working  there, 
shall  be  provided  with  respiratory  protective  equipment 
when  work  in  such  unhealthy  conditions  has  to  be 
carried  out.  The  precautionary  measures  provided  shall 
be  inspected  by  the  local  health  authorities  prior  to 
commencement  of  the  work. 

9.6.7  Safety  of  Materials 

Materials  required  for  excavation,  like  ropes,  planks 
for  gangways  and  walkways,  ladders,  etc,  shall  be 
inspected  by  the  engineer-in-charge  who  shall  ensure 
that  no  accident  shall  occur  due  to  the  failure  of  such 
materials  (see  Part  5  ‘Building  Materials'  of  the  Code). 

9.6.8  Fencing  and  Warning  Signals 

Where  excavation  is  going  on,  for  the  safety  of  public 
and  the  workers,  fencing  shall  be  erected,  if  there  is 
likelihood  of  the  public  including  cattle  frequenting  the 
area.  Sufficient  number  of  notice  boards  and  danger 
sign  lights  shall  be  provided  in  the  area  to  avoid  any 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


member  of  public  from  inadvertently  falling  into  the 
excavation.  When  excavations  are  being  done  on  roads, 
diversion  of  the  roads  shall  be  provided  with  adequate 
notice  board  and  lights  indicating  the  diversion  well 
ahead.  Where  necessary,  recourse  may  be  had  for 
additional  precautionary  measures  by  way  of  watchmen 
to  prevent  accident  to  the  general  public,  especially 
during  hours  of  darkness. 

9.6.9  Effect  of  Freezing  and  Thawing 

Due  to  expansion  of  water  when  freezing,  rock 
fragments,  boulders,  etc,  are  frequently  loosened. 
Therefore,  the  side  walls  of  the  excavation  shall  be 
constantly  watched  for  signs  of  cracks  during  a  thaw. 
When  depending  in  whole  or  in  part  on  freezing  to 
support  the  side  walls,  great  care  shall  be  taken  during 
thaws  to  provide  suitable  bracing  or  remedy  the 
condition  by  scaling  of  the  loose  material  from  the  sides. 

9.6.10  Vibrations  from  Nearby  Sources 

Vibration  due  to  adjacent  machinery,  vehicles,  rail¬ 
roads,  blasting,  piling  and  other  sources  require 
additional  precautions  to  be  taken. 

9.6.11  Precautions  While  Using  Petroleum  Powered 
Equipment 

At  the  site  of  excavation,  where  petroleum  powered 
equipment  is  used,  petroleum  vapours  are  likely  to 
accumulate  at  lower  levels  and  may  cause  fire  explosion 
under  favourable  circumstances.  Care  should,  therefore, 
be  taken  to  avoid  all  sources  of  ignition  in  such  places. 

9.7  Piling  and  Other  Deep  Foundations 

9.7.1  General 

9.7. 1.1  Safety  programme 

All  operations  shall  be  carried  out  under  the  immediate 
charge  of  a  properly  qualified  and  competent  foreman 
who  shall  also  be  responsible  for  the  safety 
arrangements  of  the  work. 

9. 7. 1.2  For  work  during  night,  lighting  of  at  least 
100  lux  intensity  shall  be  provided  at  the  work  site. 

9.7.1.3  Barricading/fencing  shall  be  provided,  wherever 
necessary,  around  the  working  area  or  the  watchmen 
provided  to  prevent  onlookers  from  trespassing  into 
the  construction  sites.  In  case  of  digging  a  bore  hole, 
precautions  shall  be  taken  that  it  is  properly  barricaded 
and  is  not  left  open  to  avoid  accidental  fall  into  the 
bore  well. 

9. 7. 1.4  The  working  area  shall  be  investigated  to 
ascertain  the  presence  of  any  buried  obstruction  and 
actual  position  of  all  service  lines  passing  through  the 
work  site  shall  be  known  before  the  work  commences. 
Particular  attention  shall  be  given  in  case  live  electrical 


cables  pass  underground,  which  may  interfere  within 
the  depth  of  the  foundation. 

9.7. 1.5  The  safety  provisions  shall  be  brought  to  the 
notice  of  all  concerned  and  matters  needing  special 
attention  shall  be  displayed  at  a  prominent  place  at  the 
work  spot. 

9.7. 1.6  All  necessary  personal  protective  equipment  like 
full  body  harnesses,  safety  helmets  and  safety  shoes, 
as  considered  suitable,  shall  be  kept  available  for  the 
use  of  persons  employed  on  the  site  and  maintained  in 
condition  suitable  for  immediate  use. 

9.7. 1.7  A  first-aid  kit  shall  be  maintained  at  the  site 
near  the  place  of  work,  to  comply  with  the  requirements 
and  provisions  for  the  work. 

9.7. 1.8  Those  engaged  in  mixing  and  stacking  of  cement 
bags  or  any  other  material  injurious  to  human  body 
shall  be  provided  with  protective  wear  suitable  for  the 
purpose.  Welders  engaged  in  the  work  of  welding  shall 
use  welding  goggles/shields,  helmets  and  gloves. 

9. 7. 1.9  Every  crane  driver  or  hoisting  appliance 
operator  shall  be  competent  to  the  satisfaction  of  the 
engineer-in-charge  and  no  person  under  the  age  of 
21  years  should  be  in-charge  of  any  hoisting  machine 
including  any  scaffolding  winch,  or  give  signals  to 
operator.  Crane  driver  and  hoisting  appliance  operator 
shall  posses  the  knowledge  of  inherent  risks  involved 
in  the  operation  of  lifting  appliances  by  undergoing  a 
formal  training  at  any  institution  of  national  importance 
acceptable  to  the  employer  and  is  medically  examined 
periodically  including  in  compliance  to  the  requirement 
as  may  be  specified  in  the  Building  and  other 
Construction  Workers 1  (Regulation  of  Employment  and 
Conditions  of  Service  Central)  Rules,  1998. 

9.7.1.10  Working  in  compressed  air,  in  case  of  deep 
foundations,  requires  several  precautions  to  be  observed 
to  safeguard  the  workers  against  severe  hazards  to  life, 
compressed  air  disease  and  related  ailments.  For 
detailed  information  regarding  safety  requirements, 
reference  may  be  made  to  good  practice  [7(27)]. 

9.7.2  Piling  Rig 

9.7.2. 1  There  are  numerous  types  ofpiling  rigs  in  piling 
work,  depending  on  the  need  for  the  site  conditions. 
While  utilizing  specialized  rigs  the  instructions  issued 
by  the  suppliers  shall  be  kept  in  view. 

9.7.2.1.1  Pile  drivers  shall  not  be  erected  in  dangerous 
proximity  to  electric  conductors. 

9.7.2. 1.2  If  two  pile  drivers  are  erected  at  one  place 
these  shall  be  separated  by  a  distance  at  least  equal  to 
the  longest  leg  in  either  rig. 

9.7. 2.2  The  frame  of  any  rig  shall  be  structurally  safe 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


37 


for  all  anticipated  dead,  live  or  wind  loads.  Whenever 
there  is  any  doubt  about  the  structural  strength,  suitable 
test  shall  be  carried  out  by  the  foreman  and  the  results 
of  the  test  recorded.  No  pile-driving  equipment  shall 
be  taken  into  use  until  it  has  been  inspected  and  found 
to  be  safe. 

9. 7.2.3  Pile  drivers  shall  be  firmly  supported  on  heavy 
timber  sills,  concrete  beds  or  other  secure  foundation. 
If  necessary,  to  prevent  danger,  pile  drivers  shall  be 
adequately  guyed. 

When  the  rig  is  not  in  use,  extra  precautionary  measures 
for  stability,  such  as  securing  them  with  minimum  four 
guys,  shall  be  adopted  to  prevent  any  accidents  due  to 
wind,  storm,  gales  and  earthquake. 

9. 1.2  A  Access  to  working  platforms  and  the  top  pulley 
shall  be  provided  by  ladders.  Working  platforms  shall 
be  protected  against  the  weather. 

9.7.2.4.1  In  tall  driven  piling  rigs  or  rigs  of  similar 
nature  where  a  ladder  is  necessary  for  regular  use,  the 
ladder  shall  be  securely  fastened  and  extended  for  the 
full  height  of  the  rig.  The  ladder  shall  also  be  maintained 
in  good  condition  at  all  times. 

9.7.2. 5  Exposed  gears,  fly  wheels,  etc,  shall  be  fully 
enclosed.  Boilers,  hoisting  drums  and  brakes  shall  be 
kept  in  good  condition  and  sheltered  from  weather, 
wherever  possible. 

9.7.2.6  Pile  driving  equipment  in  use  shall  be  inspected 
by  a  competent  engineer  at  regular  intervals  not 
exceeding  three  months.  Also  a  register  shall  be 
maintained  at  the  site  of  work  for  recording  the  results 
of  such  inspections.  Pile  lines  and  pulley  blocks  shall 
be  inspected  by  the  foreman  before  the  beginning  of 
each  shift  for  any  excess  wear  or  any  other  defect. 

9. 7. 2. 6.1  Defective  parts  of  pile  drivers,  such  as 
sheaves,  mechanism  slings  and  hose  shall  be  repaired 
by  only  competent  person  and  duly  inspected  by 
foreman-in-charge  of  the  rig  and  the  results  recorded 
in  the  register.  No  steam  or  air  equipment  shall  be 
repaired  while  it  is  in  operation  or  under  pressure. 
Hoisting  ropes  on  pile  drivers  shall  be  made  of 
galvanized  steel. 

9 .7.2.7  All  bolts  and  nuts  which  are  likely  to  be  loosened 
due  to  vibration  during  pile  driving  shall  be  checked 
regularly  and  tightened. 

9.7.2. 8  Steam  and  air  lines  shall  be  controlled  by  easily 
accessible  shut-off  valves.  These  lines  shall  consist  of 
armoured  hose  or  its  equivalent.  The  hose  of  steam  and 
air  hammers  shall  be  securely  lashed  to  the  hammer  so 
as  to  prevent  it  from  whipping  if  a  connection  breaks. 
Couplings  of  sections  of  hose  shall  be  additionally 
secured  by  ropes  or  chains. 

9. 1.2.9  When  not  in  use,  the  hammer  shall  be  in  dropped 


position  and  shall  be  held  in  place  by  a  cleat,  timber  or 
any  other  suitable  means. 

9.7.2.10  For  every  hoisting  machine  and  for  every  chain 
ring  hook,  shackle,  swivel  and  pulley  block,  used  in 
hoisting  or  as  means  of  suspension,  the  safe  working 
loads  shall  be  ascertained.  In  case  of  doubt  actual  testing 
shall  be  carried  out  and  the  working  load  shall  be  taken 
as  half  of  the  tested  load.  Every  hoisting  machine  and 
all  gears  referred  to  above  shall  be  plainly  marked  with 
the  safe  working  load.  In  case  of  a  hoisting  machine 
having  a  variable  safe  working  load,  each  safe  working 
load  together  with  the  conditions  under  which  it  is 
applicable  shall  be  clearly  indicated.  No  part  of  any 
machine  or  any  gear  shall  be  loaded  beyond  the  safe 
working  load  except  for  the  purpose  of  testing. 

All  hoisting  appliances  should  be  fitted  with  automatic 
safe  load  indicator,  boom  angle  indicator,  swing  alarm, 
back  horn,  over  lift  boom  alarm.  A  register  shall  be 
maintained  containing  a  system  of  identification  of  all 
tools  and  tackles,  their  date  of  purchase,  safe  working 
load  and  date  of  examination  by  competent  person.  All 
loads  shall  have  tag-lines  attached  in  order  to  ensure 
that  the  load  can  be  controlled  at  all  times. 

9.7.2.11  Motor  gearing,  transmission,  electrical  wiring 
and  other  dangerous  parts  of  hoisting  appliances  should 
be  provided  with  efficient  safeguards.  Hoisting 
appliances  shall  be  provided  with  such  means  as  will 
reduce,  to  the  minimum,  the  risk  of  accidental  descent 
of  the  load  and  adequate  precautions  shall  be  taken  to 
reduce  to  the  minimum,  the  risk  of  any  part  of 
suspended  load  becoming  accidentally  displaced.  When 
workers  are  employed  on  electrical  installations  which 
are  already  energized,  insulating  mats  and  wearing 
apparel,  such  as  gloves,  etc,  as  may  be  necessary,  shall 
be  provided.  Sheaves  on  pile  drivers  shall  be  guarded 
so  that  workers  may  not  be  drawn  into  them. 

When  loads  have  to  be  inclined,  they  shall  be 
adequately  counter-balanced  and  the  tilting  device  shall 
be  secured  against  slipping. 

9.7.2.12  Adequate  precautions  shall  be  taken  to  prevent 
a  pile  driver  from  overturning,  if  a  wheel  breaks. 

9.7.2.13  Adequate  precautions  shall  be  taken  by 
providing  stirrups  or  by  other  effective  means,  to 
prevent  the  rope  from  coming  out  of  the  top  pulley  or 
wheel. 

9.7.2.14  Adequate  precautions  shall  be  taken  to  prevent 
the  hammer  from  missing  the  pile. 

9.7.2.15  If  necessary  to  prevent  danger,  long  piles  and 
heavy  sheet  piling  should  be  secured  against  falling. 

9.7.2.16  Wherever  steam  boilers  are  used,  the  safety 
regulations  of  boiler  shall  be  strictly  followed  and  safety 


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valves  shall  be  adjusted  to  0.07  N/mm2  in  excess  of 
working  pressure  accurately. 

9.7.2.17  Where  electricity  is  used  as  power  for  piling 
rig,  only  armoured  cable  conforming  to  the  relevant 
Indian  Standard  shall  be  used  and  the  cable  shall  be 
thoroughly  waterproofed. 

9.7.3  Operation  of  Equipment 

9.7.3. 1  Workers  employed  in  the  vicinity  of  pile  drivers 
shall  wear  helmets  conforming  to  accepted 
standard  [7(28)]. 

9.7.3.2  Piles  shall  be  prepared  at  a  distance  at  least 
equal  to  twice  the  length  of  the  longest  pile  from  the 
pile  driver. 

9.7.3.3  Piles  being  hoisted  in  the  rig  should  be  so  slung 
that  they  do  not  have  to  be  swung  round,  and  may  not 
inadvertently,  swing  or  whip  round.  A  hand  rope  shall 
be  fastened  to  a  pile  that  is  being  hoisted  to  control  its 
movement.  While  a  pile  is  being  guided  into  position 
in  the  leads,  workers  shall  not  put  their  hands  or  arms 
between  the  pile  and  the  inside  guide  or  on  top  of  the 
pile,  but  shall  use  a  rope  for  guiding. 

9.7.3.4  While  a  pile  is  being  hoisted  all  workers  not 
actually  engaged  in  the  operation  shall  keep  at  a  distance 
which  ensures  safety.  Piles  shall  not  be  slewed  over 
public  areas  without  stopping  the  pedestrians  and  road 
traffic  first. 

9.7.3.5  Before  a  wood  pile  is  hoisted  into  position  it 
shall  be  provided  with  an  iron  ring  or  cap  over  the 
driving  end  to  prevent  brooming. 

9.7.3.6  When  creosoted  wood  piles  are  being  driven, 
adequate  precautions  shall  be  taken,  such  as  the 
provision  of  personal  protective  equipment  and  barrier 
creams  to  prevent  workers  receiving  eye  or  skin  injuries 
from  splashes  of  creosote. 

9.7.3. 7  When  piles  are  driven  at  an  inclination  to  the 
vertical,  if  necessary  to  prevent  danger,  these  should 
rest  in  a  guide. 

9.7.3. 8  No  steam  or  air  line  shall  be  blown  down  until 
all  workers  are  at  a  safe  distance. 

9.7.4  Sheet  Piling 

9.7.4. 1  If  necessary  to  prevent  danger  from  wind  or 
other  sources,  a  hand  rope  shall  be  used  to  control  the 
movement  of  steel  sheet  sections  that  are  being 
transported. 

9.7.4.2  Workers  who  have  to  sit  on  a  steel  sheet  section 
to  interlock  sheets  shall  be  provided  with  stirrups  or 
other  devices  to  afford  them  a  safe  seat.  Workers  shall 
not  stand  or  sit  on  sheet  piling  while  it  is  being  released 
from  the  slings,  lowered  or  moved  into  position. 

9.7.4.3  Workers  handling  sheets  should  wear  gloves. 


9. 7. 4. 4  If  necessary  to  prevent  danger  from 
displacement  by  the  current,  steel  sheet  sections  shall 
be  braced  until  they  are  firmly  in  position.  If  necessary 
to  prevent  danger  from  undercutting  of  the  cofferdam 
by  the  current  a  substantial  berm  shall  be  installed 
upstream. 

9.7.4.5  Adequate  pumping  facilities  shall  be  available 
at  cofferdams  to  keep  them  clear  of  water.  Also  adequate 
means  of  escape,  such  as  ladders  and  boats  shall  be 
provided  at  cofferdams  for  the  protection  of  workers 
in  case  of  flooding. 

9. 7.4. 6  Adequate  supplies  of  life-saving  equipment 
shall  be  provided  for  workers  employed  on  cofferdams. 

9.7.4. 7  When  sheet  sections  are  being  removed,  their 
movements  shall  be  controlled  by  cables  or  other 
effective  means. 

9.8  Walls 

9.8.1  General 

Depending  on  the  type  of  wall  to  be  constructed  the 
height  of  construction  per  day  shall  be  restricted  to 
ensure  that  the  newly  constructed  wall  does  not  come 
down  due  to  lack  of  strength  in  the  lower  layers. 
Similarly,  in  long  walls  adequate  expansion/crumple 
joints  shall  be  provided  to  ensure  safety. 

9.8.2  Scaffold 

Properly  designed  and  constructed  scaffolding  built  by 
competent  workers  shall  be  provided  during  the 
construction  of  the  walls  to  ensure  the  safety  of  workers. 
The  scaffolding  may  be  of  timber,  metal  or  bamboo 
sections  and  the  materials  in  scaffolding  shall  be 
inspected  for  soundness,  strength,  etc,  at  site  by  the 
engineer-in-charge  prior  to  erection  of  scaffolds.  Steel 
scaffolds  intended  for  use  in  normal  building 
construction  work  shall  conform  to  accepted  standard 
[7(29)].  Bamboo  and  timber  scaffolds  shall  be  properly 
tied  to  the  junctions  with  coir  ropes  of  sufficient  strength 
or  mechanical  joints  to  ensure  that  joints  do  not  give 
way  due  to  the  load  of  workers  and  material.  Joining 
the  members  of  scaffolds  only  with  nails  shall  be 
prohibited  as  they  are  likely  to  get  loose  under  normal 
weathering  conditions.  In  the  erection  or  maintenance 
of  tall  buildings,  scaffoldings  shall  be  of  non¬ 
combustible  material  especially  when  the  work  is  being 
done  on  any  building  in  occupation.  After  initial 
construction  of  the  scaffolding,  frequent  inspections  of 
scaffolding  shall  be  carried  out  regularly.  The  platforms, 
gangways  and  runways  provided  on  the  scaffoldings 
shall  be  of  sufficient  strength  and  width  to  ensure  safe 
passage  for  the  workers  working  on  the  scaffolding. 
The  joints  provided  in  these  gangways,  platforms,  etc, 
shall  be  such  as  to  ensure  a  firm  foot-hold  to  the 
workers.  Where  necessary,  cross  bars  shall  be  provided 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


39 


to  the  full  width  of  gangway  or  runway  to  facilitate 
safe  walking.  For  detailed  information  regarding  safety 
requirements  for  erection,  use  and  dismantling  of 
scaffolds,  reference  may  be  made  to  good  practices 
[7(30)]. 

9.8.2. 1  The  engineer-in-charge  shall  ensure  by  frequent 
inspections  that  gangways  of  scaffolding  have  not 
become  slippery  due  to  spillage  of  material.  Loose 
materials  shall  not  be  allowed  to  remain  on  the 
gangways.  Where  necessary,  because  of  height  or 
restricted  width,  hand-rails  shall  be  provided  on  both 
sides.  Workers  shall  not  be  allowed  to  work  on  the 
scaffolding  during  bad  weather  and  high  winds. 

9.8.2.2  In  the  operations  involved  in  the  erection  or 
maintenance  of  outside  walls,  fittings,  etc,  of  tall 
buildings,  it  is  desirable  to  use  one  or  more  net(s)  for 
the  safety  of  the  workers  when  the  workers  are  required 
to  work  on  scaffoldings. 

9.8.3  Ladders 

All  ladders  shall  be  constructed  of  sound  materials  and 
shall  be  capable  of  carrying  their  intended  loads  safely. 
The  ladders  shall  have  not  only  adequate  strength  but 
rigidity  as  well.  If  a  ladder  shows  tendency  to  spring,  a 
brace  shall  be  attached  to  its  middle  and  supported  from 
some  other  non-yielding  fixed  object.  No  ladder  having 
a  missing  or  defective  rung  or  one  which  depends  for 
its  support  solely  on  nails,  shall  be  used.  Ladders  shall 
not  be  used  as  guys,  braces  or  skids  or  for  any  other 
purpose  for  which  they  are  not  intended.  They  shall 
not  be  used  in  horizontal  position  as  runways.  They 
shall  not  be  overcrowded.  Wherever  possible,  ladders 
shall  not  be  spliced.  Where  splicing  is  unavoidable,  it 
shall  be  done  only  under  the  supervision  of  engineer- 
in-charge.  Ladders  leading  to  landings  or  walkways 
shall  extend  at  least  1  m  above  the  landing  and  shall  be 
secured  at  the  upper  end.  To  prevent  slipping,  a  ladder 
shall  be  secured  at  the  bottom  end.  If  this  cannot  be 
done,  a  person  shall  be  stationed  at  the  base  whenever 
it  is  in  use.  As  a  further  precaution,  the  pitch  at  which  a 
lean-to-ladder  is  used  shall  be  such  that  the  horizontal 
distance  of  its  foot  from  the  vertical  plane  of  its  top 
shall  be  not  more  than  one  quarter  of  its  length.  If  the 
surface  of  the  floor  on  which  the  ladder  rests  is  smooth 
or  sloping,  the  ladder  shall  be  provided  with  non-slip 
bases.  If  the  use  of  a  ladder  is  essential  during  strong 
winds,  it  shall  be  securely  lashed  in  position.  No  ladder 
shall  be  placed  or  leant  against  window  pane,  sashes 
or  such  other  unsafe  or  yielding  objects,  nor  placed  in 
front  of  doors  opening  towards  it.  If  set  up  in  driveways, 
passageways  or  public  walkways,  it  shall  be  protected 
by  suitable  barricades.  When  ascending  or  descending, 
the  user  shall  face  the  ladder,  use  both  his  hands  and 
place  his  feet  near  the  ends  of  the  rungs  rather  than 
near  the  middle.  It  is  dangerous  to  lean  more  than  30  cm 


to  side  in  order  to  reach  a  larger  area  from  a  single 
setting  of  the  ladder.  Instead,  the  user  shall  get  down 
and  shift  the  ladder  to  the  required  position. 

Metal  ladders  shall  not  be  used  around  electrical 
equipment  or  circuits  of  any  kind  where  there  is  a 
possibility  of  coming  in  contact  with  the  current.  Metal 
ladders  shall  be  marked  with  signs  reading  ‘CAUTION — 
DO  NOT  USE  NEAR  ELECTRICAL  EQUIPMENT’. 

Wooden  ladders  shall  be  inspected  at  least  once  in  a 
month  for  damage  and  deterioration.  Close  visual 
inspection  is  recommended  in  preference  to  load 
testing.  This  condition  is  particularly  applicable  to  rope 
and  bamboo  ladders  wherein  fraying  of  ropes  and 
damage  to  bamboo  is  likely  to  occur  due  to  materials 
falling  on  them.  When  a  ladder  has  been  accidentally 
dropped  it  shall  be  inspected  by  the  engineer-in-charge 
prior  to  re-use.  Overhead  protection  shall  be  provided 
for  workers  under  ladder.  For  detailed  information 
regarding  safety  requirements  for  use  of  ladders, 
reference  may  be  made  to  good  practice  [7(31)]. 

9.8.4  Opening  in  Walls 

Whenever  making  of  an  opening  in  the  existing  wall  is 
contemplated,  adequate  supports  against  the  collapse 
or  cracking  of  the  wall  portion  above  or  roof  or 
adjoining  walls  shall  be  provided. 

9.8.4. 1  Guarding  of  wall  openings  and  holes 

Wall  opening  barriers  and  screens  shall  be  of  such 
construction  and  mounting  that  they  are  capable  of 
withstanding  the  intended  loads  safely.  For  detailed 
information  reference  may  be  made  to  good  practice 
[7(32)].  Every  wall  opening  from  which  there  is  a  drop 
of  more  than  1  200  mm  shall  be  guarded  by  one  of  the 
following: 

a)  Rail,  roller,  picket  fence,  half  door  or 
equivalent  barrier  —  The  guard  may  be 
removable  but  should  preferably  be  hinged  or 
otherwise  mounted  so  as  to  be  conveniently 
replaceable.  Where  there  is  danger  to  persons 
working  or  passing  below  on  account  of  the 
falling  materials,  a  removable  toe  board  or  the 
equivalent  shall  also  be  provided.  When  the 
opening  is  not  in  use  for  handling  materials, 
the  guards  shall  be  kept  in  position  regardless 
of  a  door  on  the  opening.  In  addition,  a  grab 
handle  shall  be  provided  on  each  side  of  the 
opening.  The  opening  should  have  a  sill  that 
projects  above  the  floor  level  at  least  25  mm. 

b)  Extension  platform,  into  which  materials  may 
be  hoisted  for  handling,  shall  be  of  full  length 
of  the  opening  and  shall  have  side  rails  or 
equivalent  guards. 

9.8.4.2  Every  chute  wall  opening  from  which  there  is  a 


40 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


drop  of  more  than  1  200  mm  shall  be  guarded  by  one 
or  more  of  the  barriers  specified  in  9.8.4. 1  or  as  required 
by  the  conditions. 

9.8.5  Projection  from  Walls 

Whenever  projections  cantilever  out  of  the  walls, 
temporary  formwork  shall  be  provided  for  such 
projections  and  the  same  shall  not  be  removed  till  walls 
over  the  projecting  slabs  providing  stability  load  against 
overturning  are  completely  constructed. 

9.9  Common  Hazards  During  Walling 

9.9.1  Lifting  of  Materials  for  Construction 

Implements  used  for  carrying  materials  to  the  top  of 
scaffoldings  shall  be  of  adequate  strength  and  shall  not 
be  overloaded  during  the  work.  Where  workers  have 
to  work  below  scaffoldings  or  ladder,  overhead 
protection  against  the  falling  materials  shall  be 
provided.  Care  shall  be  taken  in  carrying  large  bars, 
rods,  etc,  during  construction  of  the  walls  to  prevent 
any  damage  to  property  or  injury  to  workers. 

9.9.2  Haulage  of  Materials 

9.9.2. 1  In  case  of  precast  columns,  steel  beams,  etc, 
proper  precautions  shall  be  taken  to  correctly  handle, 
use  and  position  them  with  temporary  arrangement  of 
guys  till  grouting  of  the  base. 

9.9.2.2  Manila  or  sisal  rope  shall  not  be  used  in  rainy 
season  for  hoisting  of  heavy  materials  as  they  lose  their 
strength  with  alternate  wetting  and  drying. 

9.9.3  Electical  Hazards 

No  scaffolding,  ladder,  working  platform,  gangway 
runs,  etc,  shall  exist  within  3  m  from  any  uninsulated 
electric  wire. 

9.9.4  Fire  Hazards 

Gangways  and  the  ground  below  the  scaffolding  shall 
be  kept  free  from  readily  combustible  materials 
including  waste  and  dry  vegetation  at  all  times. 

Where  extensive  use  of  blow  torch  or  other  flame  is 
anticipated  scaffoldings,  gangways,  etc,  shall  be 
constructed  with  fire  resistant  materials.  A  portable  dry 
powder  extinguisher  of  3  kg  capacity  shall  be  kept 
handy. 

9.9.5  Mechanical  Hazards 

Care  shall  be  taken  to  see  that  no  part  of  scaffolding  or 
walls  is  struck  by  truck  or  heavy  moving  equipment 
and  no  materials  shall  be  dumped  against  them  to 
prevent  any  damage.  When  such  scaffoldings  are  in  or 
near  a  public  thoroughfare,  sufficient  warning  lights 
and  boards  shall  be  provided  on  the  scaffoldings  to 
make  them  clearly  visible  to  the  public. 


9.9.6  Fragile  Materials 

During  glazing  operations,  adequate  precautions  shall 
be  taken  to  ensure  that  the  fragments  of  fragile  materials 
do  not  cause  any  injury  to  workers  or  general  public  in 
that  area  by  way  of  providing  covering  to  such  material, 
side  protection  at  work  site,  etc. 

9.10  Roofing 

9.10.1  Prevention  of  accidental  falling  of  workers 
during  the  construction  of  roofs  shall  be  ensured  by 
providing  platforms,  catch  ropes,  etc.  If  the  materials 
are  to  be  hoisted  from  the  ground  level  to  the  roof  level, 
adequate  precautions  shall  be  taken  by  way  of  correct 
technique  of  handling,  hoists  of  sufficient  strength  to 
cater  for  the  quantity  of  stores  to  be  hoisted  and 
prevention  of  overloading  such  hoists  or  buckets, 
prevention  of  overturning  of  hoists  or  buckets.  Where 
in  a  multi-storeyed  building,  the  floor  of  one  storey  is 
to  be  used  for  storage  of  materials  for  the  construction 
of  roofs,  it  shall  be  ensured  that  the  quantum  of  stores 
kept  on  the  floor  along  with  the  load  due  to  personnel 
engaged  in  the  construction  work  shall  not  exceed  the 
rated  capacity  of  the  floors. 

9.10.2  While  roofing  work  is  being  done  with 
corrugated  galvanized  iron  or  asbestos  cement  sheets, 
it  shall  be  ensured  that  joints  are  kept  secured  in  position 
and  do  not  slip,  thus  causing  injury  to  workers.  Workers 
should  not  be  allowed  to  walk  on  asbestos  cement  sheets 
but  should  be  provided  with  walking  boards.  While 
working  with  tiles,  it  shall  be  ensured  that  they  are  not 
kept  loose  on  the  roof  site  resulting  in  falling  of  tiles 
on  workers  in  lower  area.  In  slopes  of  more  than  30°  to 
the  horizontal,  the  workers  shall  use  ladders  or  other 
safety  devices  to  work  on  the  roof. 

9.10.3  If  any  glass  work  is  to  be  carried  out  in  the  roof, 
it  shall  be  ensured  that  injury  to  passerby  due  to 
breaking  of  glass  is  prevented.  During  wet  conditions, 
the  workers  shall  be  allowed  to  proceed  to  work  on  a 
sloping  roof,  only  if  the  engineer-in-charge  has  satisfied 
himself  that  the  workers  are  not  likely  to  slip  due  to 
wet  conditions. 

9.10.4  Flat  Roof 

In  any  type  of  flat  roof  construction,  any  formwork 
provided  shall  be  properly  designed  and  executed  to 
ensure  that  it  does  not  collapse  during  construction. 
During  actual  construction  of  roof,  frequent  inspection 
of  the  formwork  shall  be  carried  out  to  ensure  that  no 
damage  has  occurred  to  it. 

9.10.5  While  using  reinforcement  in  roofs,  it  shall  be 
ensured  that  enough  walking  platforms  are  provided  in 
the  reinforcement  area  to  ensure  safe  walking  to  the 
concreting  area.  Loose  wires  and  unprotected  rod  ends 
shall  be  avoided. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


41 


9.10.6  Guarding  of  Floor  Openings  and  Floor  Floles 

9.10.6.1  Every  temporary  floor  opening  shall  have 
railings,  or  shall  be  constantly  attended  by  someone. 
Every  floor  hole  into  which  persons  can  accidentally 
fall  shall  be  guarded  by  either, 

a)  a  railing  with  toe  board  on  all  exposed  sides; 
or 

b)  a  floor  hole  cover  of  adequate  strength  and  it 
should  be  hinged  in  place.  When  the  cover  is 
not  in  place,  the  floor  hole  shall  be  constantly 
attended  by  someone  or  shall  be  protected  by 
a  removable  railing. 

9.10.6.2  Every  stairway  floor  opening  shall  be  guarded 
by  a  railing  on  all  exposed  sides,  except  at  entrance  to 
stairway.  Every  ladder  way  floor  opening  or  platform 
shall  be  guarded  by  a  guard  railing  with  toe  board  on 
all  exposed  sides  (except  at  entrance  to  opening),  with 
the  passage  through  the  railing  either  provided  with  a 
swinging  gate  or  so  offset  that  a  person  cannot  walk 
directly  into  the  opening. 

9.10.6.3  Guarding  of  open-side  floors  and  platform 

Every  open-sided  floor  or  platform  1  200  mm  or  more 
above  adjacent  floor  or  ground  level  shall  be  guarded 
by  a  railing  (or  the  equivalent)  on  all  open  sides,  except 
where  there  is  entrance  to  ramp,  stair-way,  or  fixed 
ladder.  The  railing  shall  be  provided  with  a  toe  board 
beneath  the  open  sides  wherever, 

a)  persons  may  pass; 

b)  there  is  moving  machinery;  or 

c)  there  is  equipment  with  which  falling  materials 
could  create  a  hazard. 

For  detailed  information,  reference  may  be  made  to 
good  practice  [7(32)]. 

9.11  Additional  Safety  Requirements  for  Erection 
of  Concrete  Framed  Structures  (High-Rise 
Buildings) 

9.11.1  Handling  of  Plant 

9.11.1.1  Mixers 

All  gears,  chains  and  rollers  of  mixers  shall  be  properly 
guarded.  If  the  mixer  has  a  charging  skip  the  operator 
shall  ensure  that  the  workers  are  out  of  danger  before 
the  skip  is  lowered.  Railings  shall  be  provided  on  the 
ground  to  prevent  anyone  walking  under  the  skip  while 
it  is  being  lowered. 

All  cables,  clamps,  hooks,  wire  ropes,  gears  and 
clutches,  etc,  of  the  mixer,  shall  be  checked  and  cleaned, 
oiled  and  greased,  and  serviced  once  a  week.  A  trial 
run  of  the  mixer  shall  be  made  and  defects  shall  be 
removed  before  operating  a  mixer. 


When  workers  are  cleaning  the  inside  of  the  drums, 
operating  power  of  the  mixer  shall  be  locked  in  the  off 
position  and  all  fuses  shall  be  removed  and  a  suitable 
notice  hung  at  the  place. 

9.11.1.2  Cranes 

Crane  rails  where  used  shall  be  installed  on  firm  ground 
and  shall  be  properly  secured.  In  case  of  tower  cranes, 
it  shall  be  ensured  that  the  level  difference  between  the 
two  rails  remains  within  the  limits  prescribed  by  the 
manufacturer  to  safeguard  against  toppling  of  the  crane. 
Requirements  for  tower  cranes  as  given  in  7.3  shall 
also  be  complied  with. 

Electrical  wiring  which  can  possibly  touch  the  crane 
or  any  member  being  lifted  shall  be  removed,  or  made 
dead  by  removing  the  controlling  fuses  and  in  their 
absence  controlling  switches. 

All  practical  steps  shall  be  taken  to  prevent  the  cranes 
being  operated  in  dangerous  proximity  to  a  live 
overhead  power  line.  In  particular,  no  member  of  the 
crane  shall  be  permitted  to  approach  within  the 
minimum  safety  distances  as  laid  down  in  8.2.23  (a). 

If  it  becomes  necessary  to  operate  the  cranes  with 
clearances  less  than  those  specified  above,  it  shall  be 
ensured  that  the  overhead  power  lines  shall  invariably 
be  shut  off  during  the  period  of  operation  of  cranes. 
Location  of  any  underground  power  cables  in  the  area 
of  operation  shall  also  be  ascertained  and  necessary 
safety  precautions  shall  be  taken. 

Cranes  shall  not  be  used  at  a  speed  which  causes  the 
boom  to  swing. 

A  crane  shall  be  thoroughly  examined  at  least  once  in  a 
period  of  6  months  by  a  competent  person  who  shall 
record  a  certificate  of  the  check. 

The  operator  of  the  crane  shall  follow  the  safe  reach  of 
the  crane  as  shown  by  the  manufacturer. 

No  person  shall  be  lifted  or  transported  by  the  crane 
on  its  hook  or  boom. 

Toe  boards  and  limit  stops  should  be  provided  for  wheel 
barrows  on  the  loading/unloading  platforms.  Material 
should  be  loaded  securely  with  no  projections. 

Concrete  buckets  handled  by  crane  or  overhead 
cableway  shall  be  suspended  from  deep  throated  hooks, 
preferably  equipped  with  swivel  and  safety  latch.  In 
the  concrete  buckets,  both  bottom  drop  type  and  side 
drop  type,  closing  and  locking  of  the  exit  door  of  the 
bucket  shall  always  be  checked  by  the  man-in-charge 
of  loading  concrete  in  the  bucket  to  avoid  accidental 
opening  of  the  exit  door  and  consequent  falling  of 
concrete. 

Interlocking  or  other  safety  devices  should  be  installed 


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at  all  stopping  points  of  the  hoists.  The  hoists  shaft 
way  should  be  fenced  properly. 

When  the  bucket  or  other  members  being  lifted  are  out 
of  sight  of  the  crane  operator,  a  signalman  shall  be 
posted  in  clear  view  of  the  receiving  area  and  the  crane 
operator. 

A  standard  code  of  hand  signals  shall  be  adopted  in 
controlling  the  movements  of  the  crane,  and  both  the 
driver  and  the  signaller  shall  be  thoroughly  familiar 
with  the  signals. 

The  driver  of  the  crane  shall  respond  to  signals  only 
from  the  appointed  signaler  but  shall  obey  stop  signal 
at  any  time  no  matter  who  gives  it. 

If  a  travelling  gantry  crane  is  operating  over  casting 
beds,  a  warning  signal  which  sounds  automatically 
during  travel  should  be  provided  to  avoid  accidents  to 
workers  crossing  or  standing  in  the  path  of  the  moving 
loads. 

9.11.1.3  Trucks 

When  trucks  are  being  used  on  the  site,  traffic  problems 
shall  be  taken  care  of.  A  reasonably  smooth  traffic 
surface  shall  be  provided.  If  practicable,  a  loop  road 
shall  be  provided  to  permit  continuous  operation  of 
vehicles  and  to  eliminate  their  backing.  If  a  continuous 
loop  is  not  possible,  a  turnout  shall  be  provided. 
Backing  operations  shall  be  controlled  by  a  signalman 
positioned  so  as  to  have  a  clear  view  of  the  area  behind 
the  truck  and  to  be  clearly  visible  to  the  truck  driver. 
Movement  of  workers  and  plant  shall  be  routed  to  avoid 
crossing,  as  much  as  possible,  the  truck  lanes. 

9.11.1.4  Concrete  pumps  (Air  compressor  operated) 

Safety  requirements  in  accordance  with  good  practice 
[7(33)]  shall  be  followed. 

9.11.2  Formwork 

9.11.2.1  Formwork  shall  be  designed  after  taking  into 
consideration  spans,  setting  temperature  of  concrete, 
dead  load  and  working  load  to  be  supported  and  safety 
factor  for  the  materials  used  for  formwork  {see  also 
with  good  practice  [7(26)]}. 

9.11.2.2  All  timber  formwork  shall  be  carefully 
inspected  before  use  and  members  having  cracks  and 
excessive  knots  shall  be  discarded. 

9.11.2.3  As  timber  centering  usually  takes  an  initial  set 
when  vertical  load  is  applied,  the  design  of  this 
centering  shall  make  allowance  for  this  factor. 

9.11.2.4  The  vertical  supports  shall  be  adequately 
braced  or  otherwise  secured  in  position  that  these  do 
not  fall  when  the  load  gets  released  or  the  supports  are 
accidently  hit. 


9.11.2.5  Tubular  steel  centering  shall  be  used  in 
accordance  with  the  manufacturer’s  instructions.  When 
tubular  steel  and  timber  centering  is  to  be  used  in 
combination  necessary  precautions  shall  be  taken  to 
avoid  any  unequal  settlement  under  load. 

9.11.2.6  A  thorough  inspection  of  tubular  steel  centering 
is  necessary  before  its  erection  and  members  showing 
evidence  of  excessive  resting,  kinks,  dents  or  damaged 
welds  shall  be  discarded.  Buckled  or  broken  members 
shall  be  replaced.  Care  shall  also  be  taken  that  locking 
devices  are  in  good  working  order  and  that  coupling 
pins  are  effectively  aligned  to  frames. 

9.11.2.7  After  assembling  the  basic  unit,  adjustment 
screws  shall  be  set  to  their  approximate  final  adjustment 
and  the  unit  shall  be  level  and  plumb  so  that  when 
additional  frames  are  installed  the  tower  shall  be  in 
level  and  plumb.  The  centering  frames  shall  be  tied 
together  with  sufficient  braces  to  make  a  rigid  and  solid 
unit.  It  shall  be  ensured  that  struts  and  diagonals  braces 
are  in  proper  position  and  are  secured  so  that  frames 
develop  full  load  carrying  capacity.  As  erection 
progresses,  all  connecting  devices  shall  be  in  place  and 
shall  be  fastened  for  full  stability  of  joints  and  units. 

9.11.2.8  In  case  of  timber  posts,  vertical  joints  shall  be 
properly  designed.  The  connections  shall  normally  be 
with  bolts  and  nuts.  Use  of  rusted  or  spoiled  threaded 
bolts  and  nuts  shall  be  avoided. 

9.11.2.9  Unless  the  timber  centering  is  supported  by  a 
manufacturer’s  certificate  about  the  loads  it  can  stand, 
centering  shall  be  designed  by  a  competent  engineer. 

9.11.2.10  Centering  layout  shall  be  made  by  a  qualified 
engineer  and  shall  be  strictly  followed.  The  bearing 
capacity  of  the  soil  shall  be  kept  in  view  for  every 
centering  job.  The  effect  of  weather  conditions  as  dry 
clay  may  become  very  plastic  after  a  rainfall  and  show 
marked  decrease  in  its  bearing  capacity. 

9.11.2.11  Sills  under  the  supports  shall  be  set  on  firm 
soil  or  other  suitable  material  in  a  pattern  which  assures 
adequate  stability  for  all  props.  Care  shall  be  taken  not 
to  disturb  the  soil  under  the  supports.  Adequate  drainage 
shall  be  provided  to  drain  away  water  coming  due  to 
rains,  washing  of  forms  or  during  the  curing  of  the 
concrete  to  avoid  softening  of  the  supporting  soil  strata. 

9.11.2.12  All  centering  shall  be  finally,  inspected  to 
ensure  that, 

a)  footings  or  sills  under  every  post  of  the 
centering  are  sound. 

b)  all  lower  adjustment  screws  or  wedges  are 
sung  against  the  legs  of  the  panels. 

c)  all  upper  adjustment  screws  or  heads  of  jacks 
are  in  full  contact  with  the  formwork. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


43 


d)  panels  are  plumb  in  both  directions. 

e)  all  cross  braces  are  in  place  and  locking 
devices  are  in  closed  and  secure  position. 

f)  In  case  of  Chhajas  and  balconies,  the  props 
shall  be  adequate  to  transfer  the  load  to  the 
supporting  point. 

9.11.2.13  During  pouring  of  the  concrete,  the  centering 
shall  be  constantly  inspected  and  strengthened,  if 
required,  wedges  below  the  vertical  supports  tightened 
and  adjustment  screws  properly  adjusted  as  necessary. 
Adequate  protection  of  centering  shall  be  secured  from 
moving  vehicles  or  swinging  loads. 

While  pouring  concrete,  it  should  be  placed  in  such  a 
manner  that  the  load  should  be  transmitted  to  the 
support  of  formwork  uniformly  without  causing  high 
eccentric  load. 

Caution  shall  be  exercised  to  avoid  heap  storage  of 
bricks/sand  in  roof/floor  slab  as  it  may  lead  to  failure 
of  slab. 

9.11.2.14  Forms  shall  not  be  removed  earlier  than  as 
laid  down  in  the  specifications  and  until  it  is  certain 
that  the  concrete  has  developed  sufficient  strength  to 
support  itself  and  all  loads  that  will  be  imposed  on  it. 
Only  workers  actually  engaged  in  removing  the 
formwork  shall  be  allowed  in  the  area  during  these 
operations.  Those  engaged  in  removing  the  formwork 
shall  wear  helmets,  gloves  and  heavy  soled  shoes  and 
approved  safety  belts  if  adequate  footing  is  not  provided 
above  2  m  level.  While  cutting  any  tying  wires  in 
tension,  care  shall  be  taken  to  prevent  backlash  which 
might  hit  a  workman. 

9.11.2.14.1  The  particular  order  in  which  the  supports 
are  to  be  dismantled  should  be  followed  according  to 
the  instructions  of  the  site  engineer. 

9.11.3  Ramps  and  Gangways 

9.11.3.1  Ramps  and  gangways  shall  be  of  adequate 
strength  and  evenly  supported.  They  shall  either  have 
a  sufficiently  flat  slope  or  shall  have  cleats  fixed  to  the 
surface  to  prevent  slipping  of  workers.  Ramps  and 
gangways  shall  be  kept  free  from  grease,  mud,  snow  or 
other  slipping  hazards  or  other  obstructions  leading  to 
tripping  and  accidental  fall  of  a  workman. 

9.11.3.1.1  Ramps  and  gangways  meant  for  transporting 
materials  shall  have  even  surface  and  be  of  sufficient 
width  and  provided  with  skirt  boards  on  open  sides. 

9.11.4  Materials  Hoists 

9.11.4.1  The  hoist  should  be  erected  on  a  firm  base, 
adequately  supported  and  secured.  All  materials 
supporting  the  hoist  shall  be  appropriately  designed 
and  strong  enough  for  the  work  intended  and  free  from 
defects. 


9.11.4.2  The  size  of  the  drum  shall  match  the  size  of 
the  rope.  Not  less  than  two  full  turns  of  rope  shall  remain 
on  the  drum  at  all  times.  Ropes  shall  be  securely 
attached  to  the  drum. 

9.11.4.3  All  ropes,  chains  and  other  lifting  gear  shall 
be  properly  made  of  sound  materials,  free  from  defects 
and  strong  enough  for  the  work  intended.  They  shall 
be  examined  by  a  competent  person  who  shall  clearly 
certify  the  safe  working  load  on  each  item  and  the 
system. 

9.11.4.4  Hoistways  shall  be  protected  by  a  substantial 
enclosure  at  ground  level,  at  all  access  points  and 
wherever  persons  may  be  struck  by  any  moving  part. 

9.11.4.5  Gates  at  access  points  should  be  at  least  2  m 
high,  wherever  possible.  Gates  shall  be  kept  closed  at 
all  times  except  when  required  open  for  immediate 
movement  of  materials  at  that  landing  place. 

9.11.4.6  All  gates  shall  be  fitted  with  electronic  or 
mechanical  interlocks  to  prevent  movement  of  the  hoist 
in  the  event  of  a  gate  being  opened. 

9.11.4.7  Winches  used  for  hoists  shall  be  so  constructed 
that  a  brake  is  applied  when  the  control  lever  or  switch 
is  not  held  in  the  operating  position  (dead-man’s 
handle). 

9.11.4.8  The  hoist  tower  shall  be  tied  to  a  building  or 
structure  at  every  floor  level  or  at  least  every  3  m.  The 
height  of  the  tower  shall  not  exceed  6  m  after  the  last 
tie  or  a  lesser  height  as  recommended  by  the 
manufacturer.  All  ties  on  a  hoist  tower  shall  be  secured 
using  right  angled  couples. 

9.11.4.9  The  hoist  shall  be  capable  of  being  operated 
only  from  one  position  at  a  time.  It  shall  not  be  operated 
from  the  cage.  The  operator  shall  have  a  clear  view  of 
all  levels  or,  if  he  has  not,  a  clear  and  distinct  system  of 
signaling  shall  be  employed. 

9.11.4.10  All  hoist  platform  shall  be  fitted  with  guards 
and  gates  to  a  height  of  at  least  1  m,  to  prevent  materials 
rolling/falling  from  the  platform. 

9.11.4.11  Where  materials  extend  over  the  height  of 
the  platform  guards,  a  frame  shall  be  fitted  and  the 
materials  secured  to  it  during  hoisting/lowering.  Care 
should  be  taken  to  ensure  that  neither  the  frame  nor 
materials  interfere  or  touch  any  part  of  the  hoisting 
mechanism. 

9.11.4.12  The  platform  of  a  goods  hoist  shall  carry  a 
notice  stating, 

a)  the  safe  working  load;  and 

b)  that  passengers  shall  not  ride  on  the  hoist. 

9.11.4.13  All  hoist  operators  shall  be  adequately  trained 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


and  competent,  and  shall  be  responsible  for  ensuring 
that  the  hoist  is  not  overloaded  or  otherwise  misused. 

9.11.4.14  All  hoists  shall  be  tested  and  thoroughly 
examined  by  a  competent  person  before  use  on  a  site, 
after  substantial  alteration,  modification  or  repair  of 
hoists,  and  at  least  every  6  months. 

9.11.4.15  Every  hoist  shall  be  inspected  at  least  once 
each  week  by  a  competent  person  and  a  record  of  these 
inspections  kept. 

9.11.5  Prestressed  Concrete 

9.11.5.1  In  pre-stressing  operations,  operating, 
maintenance  and  replacement  instructions  of  the 
supplier  of  the  equipment  shall  be  strictly  adhered  to. 

9.11.5.2  Extreme  caution  shall  be  exercised  in  all 
operations  involving  the  use  of  stressing  equipment  as 
wires/ strands  under  high  tensile  stresses  become  a  lethal 
weapon. 

9.11.5.3  During  the  jacking  operation  of  any  tensioning 
element(s)  the  anchor  shall  be  kept  turned  up  close  to 
anchor  plate,  wherever  possible,  to  avoid  serious 
damage,  if  a  hydraulic  line  fails. 

9.11.5.4  Pulling-headers,  bolts  and  hydraulic  jacks/ 
rams  shall  be  inspected  for  signs  of  deformation  and 
failure.  Threads  on  bolts  and  nuts  should  be  frequently 
inspected  for  diminishing  cross  section.  Choked  units 
shall  be  carefully  cleaned. 

9.11.5.5  Care  shall  be  taken  that  no  one  stands  in  line 
with  the  tensioning  elements  and  jacking  equipment 
during  the  tensioning  operations  and  that  no  one  is 
directly  over  the  jacking  equipment  when  deflection  is 
being  done.  Signs  and  barriers  shall  be  provided  to 
prevent  workers  from  working  behind  the  jacks  when 
the  stressing  operation  is  in  progress. 

9.11.5.6  Necessary  shields  should  be  put  up 
immediately  behind  the  prestressing  jacks  during 
stressing  operations. 

9.11.5.7  Wedges  and  other  temporary  anchoring  devices 
shall  be  inspected  before  use. 

9.11.5.8  The  prestressing  jacks  shall  be  periodically 
examined  for  wear  and  tear. 

9.11.5.9  Prestressing  shall  be  done  in  accordance  with 
Part  6  ‘Structural  Design,  Section  5  Plain,  Reinforced 
and  Prestressed  Concrete,  Subsection  5B  Prestressed 
Concrete’  of  the  Code. 

9.11.6  Erection  of  Prefabricated  Members 

9.11.6.1  A  spreader  beam  shall  be  used  wherever 
possible  so  that  the  cable  can  be  as  perpendicular  to 
the  members  being  lifted  as  practical.  The  angle 
between  the  cable  and  the  members  to  be  lifted  shall 
not  be  less  than  60°. 


9.11.6.2  The  lifting  wires  shall  be  tested  for  double  the 
load  to  be  handled  at  least  once  in  six  months.  The  guy 
line  shall  be  of  adequate  strength  to  perform  its  function 
of  controlling  the  movement  of  members  being  lifted. 

9.11.6.3  Temporary  scaffolding  of  adequate  strength 
shall  be  used  to  support  precast  members  at 
predetermined  supporting  points  while  lifting  and 
placing  them  in  position  and  connecting  them  to  other 
members. 

9.11.6.4  After  erection  of  the  member,  it  shall  be  guyed 
and  braced  to  prevent  it  from  being  tipped  or  dislodged 
by  accidental  impact  when  setting  the  next  member. 

9.11.6.5  Precast  concrete  units  shall  be  handled  at 
specific  picking  points  and  with  specific  devices. 
Girders  and  beams  shall  be  braced  during  transportation 
and  handled  in  such  a  way  as  to  keep  the  members 
upright.  Lifting,  handling  and  installation  of 
prefabricated  members  shall  be  in  accordance  with 
Part  6  ‘Structural  Design,  Section  7  Prefabrication  and 
Systems  Building:  Subsection  7A  Prefabricated 
Concrete’  of  the  Code. 

9.11.6.6  Methods  of  assembly  and  erection  specified 
by  the  designer,  shall  be  strictly  adhered  to  at  site. 
Immediately  on  erecting  any  unit  in  position,  temporary 
connections  or  supports  as  specified  shall  be  provided 
before  releasing  the  lifting  equipment.  The  permanent 
structural  connections  shall  be  established  at  the  earliest 
opportunity. 

9.11.7  Heated  Concrete 

When  heaters  are  being  used  to  heat  aggregates  and 
other  materials  and  to  maintain  proper  curing 
temperatures,  the  heaters  shall  be  frequently  checked 
for  functioning  and  precautions  shall  be  taken  to  avoid 
hazards  in  using  coal,  liquid,  gas  or  any  other  fuel. 

9.11.8  Structural  Connections 

9.11.8.1  When  reliance  is  placed  on  bond  between 
precast  and  in-situ  concrete  the  contact  surface  of  the 
precast  units  shall  be  suitably  prepared  in  accordance 
with  the  specifications. 

9.11.8.2  The  packing  of  joints  shall  be  carried  out  in 
accordance  with  the  assembly  instructions. 

9.11.8.3  Levelling  devices,  such  as  wedges  and  nuts 
which  have  no  load  bearing  function  in  the  completed 
structure  shall  be  released  or  removed  as  necessary  prior 
to  integrating  the  joints. 

9.11.8.4  If  it  becomes  necessary  to  use  electric  power 
for  in-situ  work,  the  same  should  be  stepped  down  to  a 
safe  level  as  far  as  possible. 

9.11.9  Workers  working  in  any  position  where  there  is 
a  falling  hazard  shall  wear  safety  belts  or  other  adequate 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


45 


protection  shall  be  provided. 

9.12  Additional  Safety  Requirements  for  Erection 
of  Structural  Steel  Work 

9.12.1  Safety  Organization 

The  agency  responsible  for  erecting  the  steel  work 
should  analyze  the  proposed  erection  scheme  for  safety; 
the  erection  scheme  should  cover  safety  aspects  right 
from  the  planning  stage  up  to  the  actual  execution  of 
the  work. 

9.12.2  Safety  of  Workpersons 

9.12.2.1  General 

While  engaging  persons  for  the  job  the  supervisor 
should  check  up  and  make  sure  that  they  are  skilled  in 
the  particular  job  they  have  to  perform. 

The  helmets  shall  be  worn  properly  and  at  all  times 
during  the  work  and  shall  conform  to  the  accepted 
standard  [7(28)]. 

The  safety  goggles  shall  be  used  while  performing 
duties  which  are  hazardous  to  eye  like  drilling,  cutting 
and  welding.  The  goggles  used  shall  conform  to  the 
accepted  standard  [7(34)]  and  should  suit  individual 
workers. 

The  welders  and  gas  cutters  shall  be  equipped  with 
proper  protective  equipment  like  gloves,  safety  boots, 
aprons  and  hand  shields  [see  accepted  standard  7(35)]. 
The  filter  glass  of  the  hand  shield  shall  conform  to  the 
accepted  standard  [7(34)]  and  should  be  suitable  to  the 
eyes  of  the  particular  worker. 

When  the  work  is  in  progress,  the  area  shall  be  cordoned 
off  by  barricades  to  prevent  persons  from  hitting  against 
structural  components,  or  falling  into  excavated 
trenches  or  getting  injured  by  falling  objects. 

Warning  signs  shall  be  displayed  where  necessary  to 
indicate  hazards,  for  example  (a)  ‘440  V’,  (b)  ‘DO  NOT 
SMOKE’,  (c)  ‘MEN  WORKING  AHEAD’,  etc.  Hand 
lamps  shall  be  of  low  voltage  preferably  24  V  to  prevent 
electrical  hazards. 

All  electrically  operated  hand  tools  shall  be  provided 
with  double  earthing. 

9.12.2.2  Anchors  for  guys  or  ties  shall  be  checked  for 
proper  placement.  The  weight  of  concrete  in  which  the 
anchors  are  embedded  shall  be  checked  for  uplift  and 
sliding.  Split-end  eye  anchors  shall  only  be  used  in 
good,  solid  rock.  The  first  load  lifted  by  a  guy  derrick 
shall  be  kept  at  a  small  height  for  about  10  min  and  the 
anchors  immediately  inspected  for  any  signs  or 
indications  of  failure. 

9.12.2.3  When  a  number  of  trusses  or  deep  girders  are 
loaded  in  one  car  or  on  one  truck,  all  but  one  being 


lifted  shall  be  tied  back  unless  they  have  been  tied  or 
braced  to  prevent  their  falling  over  and  endangering 
men  unloading. 

9.12.2.4  The  erection  gang  shall  have  adequate  supply 
of  bolts,  washers,  rivets,  pins,  etc,  of  the  correct  size. 
Enough  number  of  bolts  shall  be  used  in  connecting 
each  piece  using  a  minimum  of  two  bolts  in  a  pattern 
to  ensure  that  the  joint  will  not  fail  due  to  dead  load 
and  erection  loads.  All  splice  connections  in  columns, 
crane  girders,  etc,  shall  be  completely  bolted  or  riveted 
or  welded  as  specified  in  the  drawing  before  erection. 

9.12.2.5  Girders  and  other  heavy  complicated  structural 
members  may  require  special  erection  devices  like 
cleats  and  hooks,  which  can  be  shop  assembled  and 
bolted  or  riveted  or  welded  to  the  piece  and  may  be 
left  permanently  in  the  place  after  the  work. 

9.12.2.6  If  a  piece  is  laterally  unstable  when  picked  at 
its  centre,  use  of  a  balance  beam  is  advisable,  unless  a 
pair  of  bridles  slings  can  be  placed  far  enough  apart, 
for  them  to  act  as  safe  lifting  points.  The  top  flange  of 
a  truss,  girder  or  long  beam  may  be  temporarily 
reinforced  with  a  structural  member  laid  flat  on  top  of 
the  member  and  secured  temporarily. 

9.12.2.7  On  deep  girders,  and  even  on  some  trusses,  a 
safety  ‘bar’  running  their  full  length  will  aid  the  riggers, 
fitters  and  others  employed  on  the  bottom  flange  or 
bottom  chord  to  work  with  greater  safety.  This  can  be 
a  single  16  mm  diameter  wire  rope  through  vertical 
stiffeners  of  such  members  about  1  m  above  the  bottom 
flange  and  clamped  at  the  ends  with  wire  rope  clamps. 
If  the  holes  cannot  be  provided,  short  eye  bolts  can  be 
welded  to  the  webs  of  the  girder  at  intervals  to  be 
removed  and  the  surface  chipped  or  ground  to  leave  it 
smooth  after  all  work  on  the  piece  has  been  completed. 

9.12.2.8  Safety  belts  shall  always  be  available  at  work 
spot  to  be  used,  whenever  necessary.  The  rope  shall  be 
chemically  treated  to  resist  dew  and  rotting.  These  shall 
not  be  tied  on  sharp  edges  of  steel  structures.  They  shall 
be  tied  generally  not  more  than  2  m  to  3  m  away  from 
the  belt. 

9.12.2.9  On  a  guy  derrick  or  climbing  crane  job,  the 
tool  boxes  used  by  the  erection  staff  shall  be  moved  to 
the  new  working  floor  each  time  the  rig  is  changed.  On 
a  mobile  crane  job,  the  boxes  shall  be  moved  as  soon 
as  the  crane  starts  operating  in  a  new  area  not  too  far 
away  for  the  men  to  reach  the  boxes  conveniently.  While 
working  a  tall  and  heavy  guy  derrick,  it  is  advisable  to 
control  tension  in  guys  by  hand  winches  to  avoid  jerks, 
which  may  cause  an  accident. 

9.12.2.10  The  proper  size,  number  and  spacing  of  wire 
rope  clamps  shall  be  used,  depending  on  the  diameter 
of  the  wire  rope.  They  shall  be  properly  fixed  in 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


accordance  with  the  procedure  given  in  the  accepted 
standard  [7(36)].  They  shall  be  checked  as  soon  as  the 
rope  has  been  stretched,  as  the  rope,  especially  if  new, 
tends  to  stretch  under  the  applied  load,  which  in  turn 
may  cause  it  to  shrink  slightly  in  diameter.  The  clamps 
shall  then  be  promptly  tightened  to  take  care  of  this 
new  condition.  In  addition,  the  clamps  shall  be 
inspected  frequently  to  be  sure  that  they  have  not 
slipped  and  are  tight  enough. 

9.12.2.11  When  the  men  can  work  safely  from  the  steel 
structure  itself,  this  is  preferable  to  hanging  platforms 
or  scaffolds,  as  it  eliminates  additional  operations, 
which  in  turn,  reduces  the  hazard  of  an  accident.  To 
aid  men  working  on  floats  or  scaffolds,  as  well  as  men 
in  erection  gangs,  or  other  gangs  using  small  material, 
such  as  bolts  and  drift  pins,  adequate  bolt  baskets  or 
similar  containers  with  handles  of  sufficient  strength 
and  attachment  to  carry  the  loaded  containers,  shall  be 
provided.  The  men  should  be  trained  to  use  such 
containers,  and  to  keep  small  tools  gathered  up  and 
put  away  in  tool  boxes  when  not  in  use.  Material  shall 
not  be  dumped  overboard  when  a  scaffold  is  to  be 
moved.  Rivet  heaters  shall  have  safe  containers  or 
buckets  for  hot  rivets  left  over  at  the  end  of  the  day. 

9.12.2.12  During  the  erection  of  tall  buildings,  it  is 
desirable  to  use  nylon  nets  of  sufficient  width  at  a  height 
of  3  m  to  4  m  from  ground  to  provide  safety  to  people. 
The  safety  net  should  be  made  from  man-made  or 
machine-made  fibre  ropes  which  are  UV  stabilized  and 
conforming  to  the  accepted  standard  [7(37)]. 

9.12.2.13  Safety  against  fire 

A  fire  protection  procedure  is  to  be  set  up  if  there  is  to 
be  any  flame  cutting,  burning,  heating,  riveting  or  any 
operation  that  could  start  a  fire.  For  precautions  to  be 
observed  during  welding  and  cutting  operations, 
reference  may  be  made  to  good  practice  [7(38)].  The 
workers  should  be  instructed  not  to  throw  objects  like 
hot  rivets,  cigarette  stubs,  etc,  around.  Sufficient  fire 
extinguishers  shall  be  placed  at  strategic  points. 
Extinguishers  shall  always  be  placed  in  cranes,  hoists, 
compressors  and  similar  places.  Where  electrical 
equipment  are  involved,  CO,  or  dry  powder  extinguishers 
shall  be  provided  {see  also  good  practice  [7(24)]}. 

9.12.2.14  Riding  on  a  load,  tackle  or  runner  shall  be 
prohibited. 

9.12.2.15  The  load  shall  never  be  allowed  to  rest  on 
wire  ropes.  Ropes  in  operation  should  not  be  touched. 
Wire  rope  with  broken  strand  shall  not  be  used  for 
erection  work.  Wire  ropes/manila  ropes  conforming  to 
acceptable  standards  [7(39)]  shall  be  used  for  guying. 

9.12.2.16  Lifting  appliances 

Precautions  as  laid  down  in  9.11.1.2  shall  be  followed. 


9.12.2.17  Slinging 

Chains  shall  not  be  joined  by  bolting  or  wiring  links 
together.  They  shall  not  be  shortened  by  tying  knots.  A 
chain  in  which  the  links  are  locked,  stretched  or  do  not 
move  freely  shall  not  be  used.  The  chain  shall  be  free 
of  kinks  and  twists.  Proper  eye  splices  shall  be  used  to 
attach  the  chain  hooks. 

Pulley  blocks  of  the  proper  size  shall  be  used  to  allow 
the  rope  free  play  in  the  sheave  grooves  and  to  protect 
the  wire  rope  from  sharp  bends  under  load.  Idle  sling 
should  not  be  carried  on  the  crane  hook  alongwith  a 
loaded  sling.  When  idle  slings  are  carried  they  shall  be 
hooked. 

While  using  multilegged  slings,  each  sling  or  leg  shall 
be  loaded  evenly  and  the  slings  shall  be  of  sufficient 
length  to  avoid  a  wide  angle  between  the  legs. 

9.12.2.18  Riveting  operations 

9.12.2.18.1  Handling  rivets 

Care  shall  be  taken  while  handling  rivets  so  that  they 
do  not  fall,  strike  or  cause  injury  to  men  and  material 
below.  Rivet  catchers  shall  have  false  wooden  bottoms 
to  prevent  rivets  from  rebounding. 

9.12.2.18.2  Riveting  dollies 

Canvas,  leather  or  rope  slings  shall  be  used  for  riveting 
dollies.  Chain  shall  not  be  used  for  the  purpose. 

9.12.2.18.3  Riveting  hammers 

Snaps  and  plungers  of  pneumatic  riveting  hammers 
shall  be  secured  to  prevent  the  snap  from  dropping  out 
of  place.  The  nozzle  of  the  hammer  shall  be  inspected 
periodically  and  the  wire  attachment  renewed  when 
born. 

9.12.2.18.4  Fire  protection 

The  rivet  heating  equipment  should  be  as  near  as 
possible  to  the  place  of  work.  A  pail  of  water  shall 
always  be  kept  ready  for  quenching  the  fire  during 
riveting  operations  and  to  prevent  fires  when  working 
near  inflammable  materials. 

9.12.2.19  Welding  and  gas  cutting 

9.12.2.19.1  For  safety  and  health  requirements  in 
electric  gas  welding  and  cutting  operations,  reference 
may  be  made  to  good  practice  [7(40)].  The 
recommendations  given  in  9.12.2.19.2  to  9.12.2.19.4 
are  also  applicable. 

9.12.2.19.2  All  gas  cylinders  shall  be  used  and  stored 
in  the  upright  position  only  and  shall  be  conveyed  in 
trolleys.  While  handling  by  cranes  they  shall  be  carried 
in  cages.  The  cylinders  shall  be  marked  ‘full’  or  ‘empty’ 
as  the  case  may  be.  Gas  cylinders  shall  be  stored  away 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


47 


from  open  flames  and  other  sources  of  heat.  Oxygen 
cylinders  shall  not  be  stored  near  combustible  gas,  oil, 
grease  and  similar  combustible  materials.  When  the 
cylinders  are  in  use,  cylinder  valve  key  or  wrench  shall 
be  placed  in  position.  Before  a  cylinder  is  moved, 
cylinder  valve  shall  be  closed.  All  cylinder  valves  shall 
be  closed  when  the  torches  are  being  replaced  or 
welding  is  stopped  for  some  reason.  The  cylinder  valve 
and  connections  shall  not  be  lubricated. 

9.12.2.19.3  Gas  cutting  and  welding  torches  shall  be 
lighted  by  means  of  special  lighters  and  not  with 
matches.  The  cables  from  welding  equipment  should 
be  placed  in  such  a  way  that  they  are  not  run  over  by 
traffic.  Double  earthing  shall  be  provided.  Before 
undertaking  welding  operations  near  combustible 
materials,  suitable  blanketing  shall  be  provided  and  fire 
extinguishers  kept  nearby.  Welding  shall  not  be 
undertaken  in  areas  where  inflammable  liquids  and 
gases  are  stored. 

9.12.2.19.4  Gas  lines  and  compressed  air  lines  shall 
be  identified  by  suitable  colour  codes  for  easy 
identification,  to  avoid  confusion  and  to  prevent  fire 
and  explosion  hazards. 

9.12.3  Safety  of  Structure 

9.12.3.1  General 

The  structure  itself  should  be  safeguarded  during  its 
erection.  The  first  truss  of  the  roof  system  shall  be  guyed 
on  each  side  before  the  hoisting  rope  is  detached  from 
it.  After  the  subsequent  trusses  and  roof  purlins  are 
erected,  protective  guides  shall  be  firmly  established 
and  the  required  wind  bracings  shall  be  erected  to 
prevent  the  whole  structure  being  blown  over  by  a 
sudden  gale  at  night.  Bracing  and  guying  precautions 
shall  be  taken  on  every  structure  until  it  is  complete. 
Guying  shall  be  specifically  done  for  trusses  and 
structural  components  which  after  their  erection  form 
an  erection  device.  On  structures  used  for  temporary 
material  storage  overloading  shall  be  avoided. 

9.12.3.1.1  Erection  of  columns  shall  be  immediately 
followed  by  vertical  bracing  between  columns  before 
the  roof  structure  is  erected. 

9.13  Miscellaneous  Items 

9.13.1  Staircase  Construction 

While  staircase  is  under  construction,  depending  on 
the  type  of  construction,  namely,  concrete  or  brickwork, 
etc,  suitable  precautions  shall  be  taken  by  way  of 
support,  formworks,  etc,  to  prevent  any  collapse. 
Workers  or  any  other  person  shall  not  be  allowed  to 
use  such  staircases  till  they  are  tested  and  found  fit  for 
usage  by  the  Authority/engineer-in-charge.  Till  the 
pennanent  handrails  are  provided,  temporary  provisions 


like  ropes,  etc,  shall  be  provided  on  staircases  prior  to 
commencement  of  use  of  such  staircases. 

9.13.2  Lift  Wells 

Till  the  installation  of  the  lift  is  completed,  lift  wells 
shall  be  protected  with  check  boards  or  railings  together 
with  notice  boards,  danger  lights,  etc,  to  prevent  persons 
accidentally  falling  into  the  wells.  The  handrails 
provided  shall  be  capable  of  withstanding  pressure 
exerted  due  to  normal  bumping  of  an  individual  against 
the  same. 

9.13.3  Construction  Involving  the  Use  of  Hot 
Bituminous  Tar  Materials 

9.13.3.1  Safety’  programme 

9.13.3.1.1  General 

On  all  major  works,  an  experienced  and  competent 
foreman  or  supervisor  shall  be  placed  in-charge  of  the 
work,  and  shall  be  made  responsible  for  the  strict 
observance  of  the  safety  rules.  He  shall  stock  the 
necessary  protective  equipment,  fire  extinguishing 
equipment,  first-aid  kit,  etc.  He  shall  also  keep  a  record 
of  the  accidents  taking  place  on  any  particular  job,  with 
reasons  thereof,  and  shall  suggest  suitable  remedial 
measures  to  the  management  for  prevention  thereof. 

9.13.3.1.2  Protective  covering 

Workers  engaged  on  jobs  involving  handling  of  hot 
bitumen,  tar,  and  bituminous  mixtures  shall  use 
protective  wears,  such  as  boots  and  gloves,  preferably 
of  asbestos  or  otherwise  of  rubber;  goggles  and  helmet. 
No  workers  shall  be  permitted  to  handle  such  materials 
without  wearing  the  needed  protective  covering. 

9.13.3.1.3  Fire  fighting  arrangements 

When  heating  and  handling  of  hot  bituminous  materials 
is  to  be  done  in  the  open,  sufficient  stocks  of  clean  dry 
sand  or  loose  earth  shall  be  made  available  at  the  work 
site  to  cope  with  any  resultant  fires.  When  neither  such 
materials  are  available,  nor  are  any  suitable  type  of  fire 
extinguishers  provided  at  the  work  site  in  the  open, 
and  reliance  has  to  be  on  using  water  for  fighting  any 
fire,  the  water  supply  available  should  be  in  abundance 
and  the  water  shall  be  applied  to  the  fire  in  the  form  of 
spray.  When  heating  of  bituminous  materials  is  carried 
out  in  enclosed  spaces,  sufficient  number  of  properly 
maintained  dry  powder  fire  extinguisher  or  foam 
extinguisher  conforming  to  accepted  standards  [7(23)] 
shall  be  kept  in  readiness  on  the  work  site. 

9.13.3.2  Sprayer,  spreader/paver 

9.13.3.2.1  Sprayer 

The  sprayer  shall  be  provided  with  a  fire  resisting 
screen.  The  screen  shall  have  an  observation  window. 


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Piping  for  hot  tar  and  bitumen  shall  be  adequately 
insulated  to  protect  workers  from  injury  by  bums. 
Flexible  piping  work  under  positive  pressure  shall  be 
of  metal  which  shall  be  adequately  insulated.  Workers 
shall  not  stand  facing  the  wind  directions  while  spraying 
hot  binder,  lest  it  may  fall  on  them  causing  bums. 

9.13.3.2.2  Spreader/Paver 

Spreaders  in  operation  shall  be  protected  by  signals, 
signs  or  other  effective  means.  People  should  be  warned 
against  walking  over  hot  mixture  laid.  Gravel  spreaders 
shall  always  keep  a  safe  distance  from  sprayer.  Elevated 
platforms  on  spreaders  shall  be  protected  by  suitable 
railing  and  be  provided  with  an  access  ladder. 

9.13.3.3  Equipment  for  heating  of  bitumen  and  tars 

9.13.3.3.1  Tanks,  vats,  kettles,  pots,  drums  and  other 
vessels  for  heating  tar,  bitumen  and  other  bituminous 
materials  shall  be, 

a)  adequately  resistant  to  damage  by  heat, 
transportation,  etc; 

b)  capable  of  holding  a  full  load  without  danger 
of  collapse,  bursting  or  distortion; 

c)  provided  with  a  close  fitting  cover  suitable  for 
smothering  a  fire  in  the  vessel  or  protection 
from  rain;  and 

d)  leak  proof,  and  provided  with  suitable  outlets 
which  can  be  controlled  for  taking  out  the  hot 
material. 

9.13.3.3.2  Suitable  indicator  gauges  shall  be  used  to 
ascertain  level  and  temperature  of  the  material  in  the 
boiler.  On  no  account  shall  workers  be  allowed  to  peep 
into  the  boiler  for  this  purpose.  For  ascertaining  levels, 
in  small  plants,  dipstick  may  also  be  used. 

9.13.3.3.3  Gas  and  oil-fired  bitumen  and  tar  kettles  or 
pots  shall  be  equipped  with  burners,  regulators  and 
safety  devices  of  types  approved  by  the  Authority, 
bleating  appliances  for  vessels  shall  distribute  the  heat 
uniformly  over  the  heating  surface  so  as  to  avoid 
overheating.  In  case  of  bituminous  mixtures  using 
mineral  aggregates  filler  together  with  bitumen,  it  is 
preferable  to  have  some  means  for  stirring  as  well.  Only 
vessels  heated  by  electricity  shall  be  used  inside 
buildings.  Tar  boilers  shall  never  be  used  on 
combustible  roof. 

9.13.3.3.4  Buckets  for  hot  bitumen,  bituminous 
materials  of  tar  shall  have, 

a)  the  bail  or  handle  firmly  secured;  and 

b)  a  second  handle  near  the  bottom  for  tipping. 

9.13.3.3.5  Bitumen  or  tar  boilers  mounted  on  wheels 
for  easy  transport  or  towing  shall  preferably  be  provided 
with  hand  pumps  for  spraying  purposes. 


9.13.3.3.6  Vessels  in  operation  shall  be  kept  at  a  safe 
distance  from  combustible  materials.  When  vessels  are 
used  in  confined  spaces,  the  gases,  fumes  and  smoke 
generated  shall  be  removed  by  exhaust  ventilation  or 
by  forced  ventilations.  Vessels  that  are  being  heated 
shall  not  be  left  unattended.  Pieces  of  bituminous 
material  shall  not  be  thrown  into  the  hot  vessels  so  as 
to  cause  splashing.  Covers  shall  be  kept  closed  when 
vessels  are  not  in  use.  Containers  shall  not  be  filled 
with  hot  bitumen  or  tar  to  a  level  that  might  cause  danger 
when  they  are  carried  or  hoisted.  Enough  space  shall 
be  left  in  vessels  for  expansion  of  binder,  when  heated. 

9.13.3.3.7  Bitumen/tar  shall  be  kept  dry  and  to  avoid 
fire  due  to  foaming,  boiler  shall  have  a  device  that 
prevents  foam  from  reaching  the  burners  or  anti¬ 
foaming  agents  shall  be  used  to  control  the  same. 
Alternatively,  to  avoid  fire  due  to  foaming,  the  heating 
shall  be  at  low  temperature  till  the  water  entrapped,  if 
any,  is  completely  evaporated.  Any  water  present  in 
the  boiler  shall  also  be  drained  before  using  it  for 
heating  binders.  No  open  light  shall  be  used  for 
ascertaining  the  level  of  binder  in  boilers.  If  a  burner 
goes  out,  the  fuel  supply  shall  be  cut  off  and  the  heating 
tube  shall  be  thoroughly  blown  out  by  the  fan  so  as  to 
prevent  a  back  fire. 

9.13.3.3.8  Cutbacks  shall  not  be  heated  over  an  open 
flame  unless  a  water  jacket  is  used.  While  they  are  being 
heated  the  vessel  shall  be  kept  open. 

9.13.3.3.9  Piping  shall  not  be  warmed  with  burning  rags 
and  instead  blow-lamps  or  similar  devices  shall  be  used. 

9.13.3.3.10  Spilled  bitumen  or  tar  shall  be  promptly 
cleaned  up  around  boilers. 

9.13.3.3.11  Inspection  openings  shall  not  be  opened 
while  there  is  any  pressure  in  the  boiler. 

9.13.3.3.12  When  tanks  are  cleaned  by  steam,  adequate 
precautions  shall  be  taken  to  prevent  any  build  up  of 
pressure. 

9.13.3.4  Handling  bitumen/tar 

Bitumen/tar  shall  not  be  heated  beyond  the  temperature 
recommended  by  the  manufacturer  of  the  product. 
While  discharging  heated  binder  from  the  boiler, 
workers  shall  not  stand  opposite  to  the  jet  so  as  to  avoid 
the  possibility  of  hot  binder  falling  on  them.  The 
container  shall  be  handled  only  after  closing  the  control 
valve.  While  handling  hot  bitumen/tar,  workers  shall 
exercise  scrupulous  care  to  prevent  accidental  spillage 
thereof.  The  buckets  and  cans  in  which  the  hot  material 
is  carried  from  boiler  shall  be  checked  before  use  to 
ensure  that  they  are  intact  and  safe.  Mops  and  other 
applicators  contaminated  with  bituminous  materials 
shall  not  be  stored  inside  buildings. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


49 


9.13.3.5  Bitumen  plants 

Safety  requirements  shall  be  in  accordance  with  good 
practice  [7(41)]. 

9.13.4  Timber  Structure 

Preventive  measures  against  hazards  in  work  places 
involving  construction  of  timber  structures  shall  be 
taken  in  accordance  with  good  practice  [7(42)]. 

9.14  Finishes 

9.14.1  Painting,  Polishing  and  Other  Finishes 

Only  the  quantity  of  paint,  thinner  and  polish  required 
for  the  day’s  work  should  be  kept  at  the  work  spot. 

9.14.1.1  All  containers  of  paint,  thinner  and  polish 
which  are  not  in  actual  use  should  be  closed  with  tight 
fitting  lids  and  kept  at  a  safe  place  away  from  the  actual 
work  site. 

9.14.1.2  A  5  kg  dry  powder  fire  extinguisher 
conforming  to  the  accepted  standard  [7(43)]  shall  be 
kept  handy. 

9.14.1.3  Metal  receptacles  with  pedal  operated  metal 
lids  shall  be  kept  handy  at  the  work  site  for  depositing 
used  cotton  rags/waste.  The  contents  of  such  receptacles 
shall  be  disposed  off  before  the  end  of  each  day’s  work 
at  a  safe  place,  preferably  by  burning  under  proper 
supervision. 

9.14.1.4  All  containers  of  paint  shall  be  removed  from 
the  work  site  and  deposited  in  the  paint  store  before 
the  close  of  day’s  work.  Used  paint  brushes  shall  be 
cleaned  and  deposited  in  the  store  along  with  the 
containers. 

9.14.1.5  Some  paints/polishing  and  finishing  materials 
are  injurious  to  the  health  of  workers.  Adequate 
protective  clothing,  respiratory  equipment,  etc,  shall 
be  provided  for  the  use  of  workers  during  such 
operations  where  necessary. 

9.15  Fragile  Fixtures 

It  shall  be  ensured  that  sufficient  number  of  workers 
and  equipment  are  provided  to  carry  the  fragile  fixtures 
like  sanitary  fittings,  glass  panes,  etc,  to  prevent  injury 
to  workers  due  to  accidental  dropping  of  such  fixtures. 

9.16  Safety  in  Special  Operations 

Safety  in  compressed  air  work,  drilling,  blasting  and 
welding  operations  shall  be  in  accordance  with  good 
practices  [7(44)]. 

9.17  Electrical  Installations  and  Lifts 

9.17.1  Temporary  Electrical  Wiring 

9.17.1.1  Frayed  and/or  bare  wires  shall  not  be  used  for 
temporary  electrical  connections  during  construction. 

50 


All  temporary  wiring  shall  be  installed  and  supervised 
by  a  competent  electrician.  Adequate  protection  shall 
be  provided  for  all  electrical  wiring  laid  on  floor  which 
may  have  to  be  crossed  over  by  construction  machinery 
or  by  the  workers.  All  flexible  wiring  connecting  the 
electrical  appliances  shall  have  adequate  mechanical 
strength  and  shall  preferably  be  enclosed  in  a  flexible 
metal  sheath.  Overhead  wires/cables  shall  be  so  laid 
that  they  leave  adequate  head  room. 

9.17.1.2  All  electrical  circuits,  other  than  those  required 
for  illumination  of  the  site  at  night,  shall  be  switched 
off  at  the  close  of  day’s  work.  The  main  switch  board 
from  which  connections  are  taken  for  lighting,  power 
operated  machinery,  etc,  shall  be  located  in  an  easily 
accessible  and  prominent  place.  No  articles  of  clothing 
nor  stores  shall  be  kept  at  the  back  of  or  over  the  board 
or  anywhere  near  it.  One  3  kg/4.5  kg  C02  extinguisher 
or  one  5  kg  dry  powder  extinguisher  conforming  to  the 
accepted  standard  [7(43)]  shall  be  provided  near  the 
switch  board. 

9.7. 1.3  Requirements  as  given  in  12  of  Part  8  ‘Building 
Services,  Section  2  Electrical  and  Allied  Installations’ 
of  the  Code  shall  also  be  complied  with. 

9.17.2  Permanent  Electrical  Installations 

Besides  the  fire  safety  measures  for  electrical 
installations  covered  under  9.17.1,  safety  in  electric 
installations  in  buildings  and  installations  of  lifts  shall 
be  in  accordance  with  12  of  Part  8  ‘Building  Services, 
Section  2  Electrical  and  Allied  Installations’  of  the 
Code,  and  Part  8  ‘Building  Services,  Section  5 
Installation  of  Lifts,  Escalators  and  Moving  Walks’  of 
the  Code,  respectively. 

9.18  General  Safety  Requirements  for  Workplace 

9.18.1  Sanitation 

a)  Adequate  toilet  facilities  shall  be  provided  for 
the  workers  within  easy  access  of  their  place 
of  work.  The  total  number  to  be  provided  shall 
be  not  less  than  one  per  30  employees  in  any 
one  shift. 

b)  Toilet  facilities  shall  be  provided  from  the  start 
of  building  operations,  and  connection  to  a 
sewer  shall  be  made  as  soon  as  practicable. 

c)  Every  toilet  shall  be  so  constructed  that  the 
occupant  is  sheltered  from  view  and  protected 
from  the  weather  and  falling  objects. 

d)  Toilet  facilities  shall  be  maintained  in  a 
sanitary  condition.  A  sufficient  quantity  of 
disinfectant  shall  be  provided.  Natural  or 
artificial  illumination  shall  be  provided. 

NATIONAL  BUILDING  CODE  OF  INDIA  2016 


e)  An  adequate  supply  of  drinking  water  shall 
be  provided,  and  unless  connected  to  a 
municipal  water  supply,  samples  of  the  water 
shall  be  tested  at  frequent  intervals  by  the 
Authority. 

9.18.2  Fire  Protection 

9.18.2.1  In  addition  to  the  provision  of  fire  extinguishers, 
as  specified  in  this  part  of  the  Code,  other  fire  extinguishing 
equipment  shall  also  be  provided  and  conveniently  located 
within  the  building  under  construction  or  on  the  building 
site,  as  required  by  the  Authority. 

9.18.2.1.1  All  fire  extinguishers  shall  be  maintained  in 
a  serviceable  condition  at  all  times  in  accordance  with 
good  practice  [7(24)]  and  all  necessary  guidelines 
regarding  fire  protection  at  workplaces  followed  in 
accordance  with  good  practice  [7(21)]. 

9.18.2.1.2  It  shall  be  ensured  that  all  workers  and 
supervisory  staff  are  fully  conversant  with  the  correct 
operation  and  use  of  fire  extinguishers  provided  at  the 
construction  site. 

9.18.2.1.3  Telephone  number  of  local  fire  brigade 
should  be  prominently  displayed  near  each  telephone 
provided  at  construction  site. 

9.18.2.1.4  Watch  and  ward  services  should  be  provided 
at  construction  sites  during  holidays  and  nights. 

9.18.2.2  Access  shall  be  provided  and  maintained  at 
all  times  to  all  fire  fighting  equipment,  including  fire 
hose,  extinguishers,  sprinkler  valves  and  hydrants. 

9.18.2.2.1  Approach  roads  for  fire  fighting  should  be 
planned,  properly  maintained  and  kept  free  from 
blockage.  Width  of  approach  road  should  be  not  less 
than  5  m  to  facilitate  fire  fighting  operations. 

9.18.2.2.2  Emergency  plan  and  fire  order  specifying 
the  individual  responsibility  in  the  event  of  fire  should 
be  formulated  and  mock  drills  should  be  practised 
periodically  in  case  of  large  and  important  construction 
sites  to  ensure  upkeep  and  efficiency  of  fire  fighting 
appliances. 

9.18.2.2.3  Periodical  inspection  should  be  carried  out 
to  identify  any  hazard  and  proper  records  maintained 
and  follow  up  action  taken. 

9.18.2.2.4  Evacuation  facilities  and  fire  exits  should 
be  provided  at  all  locations  susceptible  to  fire  hazards. 

9.18.2.3  Where  the  building  plans  require  the 
installation  of  fixed  fire  fighting  equipment,  such  as 
hydrants,  stand  pipes,  sprinklers  and  underground  water 
mains  or  other  suitable  arrangements  for  provision  of 
water  shall  be  installed,  completed  and  made  available 
for  permanent  use  as  soon  as  possible,  but  in  any  case 
not  later  than  the  stage  at  which  the  hydrants,  etc,  are 


required  for  use  as  specified  in  9.18.2.3.1  to  9.18.2.3.4, 

9.18.2.3.1  A  stand  pipe  system  (landing  valves), 
permanent  in  nature  shall  be  installed  and  made 
available  before  the  building  has  reached  the  height  of 
15m  above  the  grade,  and  carried  up  with  each  floor. 

9.18.2.3.2  The  standpipe  (landing  valve/intemal  fire 
hydrant)  and  its  installation  shall  conform  to  the 
accepted  standards  [7(45)]. 

9.18.2.3.3  The  standpipe  shall  be  carried  up  with  each 
floor  and  securely  capped  at  the  top.  Top  hose  outlets, 
should  at  all  times,  be  not  more  than  one  floor  below 
the  floor  under  construction. 

9.18.2.3.4  A  substantial  box,  preferably  of  metal,  should 
be  provided  and  maintained  near  each  hose  outlet.  The 
box  should  contain  adequate  lengths  of  hose  to  reach 
all  parts  of  the  floor  as  well  as  a  short  branch  fitted 
with  12  mm  or  20  mm  nozzle. 

9.18.2.4  Close  liaison  shall  be  maintained  with  the  local 
Fire  Brigade,  during  construction  of  all  buildings  above 
15  m  in  height  and  special  occupancies,  like 
educational,  assembly,  institutional,  industrial,  storage, 
hazardous  and  mixed  occupancies  with  any  of  the 
aforesaid  occupancies  having  area  more  than  500  m2 
on  each  floor. 

9.18.2.5  It  is  desirable  that  telephone  system  or  other 
means  of  inter-communication  system  be  provided 
during  the  construction  of  all  buildings  over  15  m  in 
height  or  buildings  having  a  plinth  area  in  excess 
of  1  000  m2. 

9.18.2.6  All  work  waste,  such  as  scrap  timber,  wood 
shavings,  sawdust,  paper,  packing  materials  and  oily 
waste  shall  be  collected  and  disposed  of  safely  at  the 
end  of  each  day’s  work.  Particular  care  shall  be  taken 
to  remove  all  waste  accumulation  in  or  near  vertical 
shaft  openings  like  stairways,  lift-shaft,  etc. 

9.18.2.7  An  independent  water  storage  facility  shall  be 
provided  before  the  commencement  of  construction 
operations  for  fire-fighting  purposes.  It  shall  be 
maintained  and  be  available  for  use  at  all  times. 

9.18.2.8  Fire  cut-offs 

Fire  walls  and  exit  stairways  required  for  a  building 
should  be  given  construction  priority.  Where  fire  doors, 
with  or  without  automatic  closing  devices,  are  stipulated 
in  the  building  plans  they  should  be  hung  as  soon  as 
practicable  and  before  any  significant  quantity  of 
combustible  material  is  introduced  in  the  building. 

9.18.2.8.1  As  the  work  progresses,  the  provision  of 
permanent  stairways,  stairway  enclosures,  fire  walls  and 
other  features  of  the  completed  structure  which  will 
prevent  the  horizontal  and  vertical  spread  of  fire  should 
be  ensured. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


51 


9.18.3  Clothing 

9.18.3.1  It  shall  be  ensured  that  the  clothes  worn  by 
the  workers  be  not  of  such  nature  as  to  increase  the 
chances  of  their  getting  involved  in  accident  to 
themselves  or  to  others.  As  a  rule,  wearing  of  Chaddars 
or  loose  garments  shall  be  prohibited. 

9.18.3.2  Workers  engaged  in  processes  which  splash 
liquid  or  other  materials  which  will  injure  the  skin  shall 
have  enough  protective  clothing  to  cover  the  body. 

9.18.3.3  Individuals  engaged  in  work  involving  use  of 
naked  flames  (such  as  welding)  shall  not  wear  synthetic 
fibre  or  similar  clothing  which  increases  the  risk  of  fire 
hazards. 

9.18.4  Safety  Measures  Against  Fall  Prevention 

Persons  working  at  heights  may  use  safety  belts  and 
harnesses.  Provision  of  cat-walks,  wire  mesh,  railings 
reduces  chances  of  fall-ladder  and  scaffoldings, 
stagings,  etc,  should  be  anchored  on  firm  footing  and 
should  be  secured  and  railing  should  be  provided  as 
far  as  possible.  All  accesses  should  be  barricaded  to 
prevent  accidental  fall.  For  details  as  fall  prevention 
reference  may  be  made  to  good  practice  [7(46)]. 

9.18.5  Falling  Materials  Hazard  Prevention 

Preventive  measures  against  falling  materials  hazards 
in  work  places  shall  be  taken  in  accordance  with  good 
practice  [7(47)]. 

9.18.6  Disposal  of  Debris 

Preventive  measures  against  hazards  relating  to  disposal 
of  debris  shall  be  taken  in  accordance  with  [7(48)]. 

9.19  Construction  Machinery 

9.19.1  Specification  and  requirements  of  construction 
machinery  used  in  construction  or  demolition  work  shall 
conform  to  accepted  standards  [7(49)]. 

9.19.2  For  safety  requirements  for  working  with 
construction  machinery,  reference  may  be  made  to  good 
practice  [7(50)]. 

9.19.3  Petroleum  powered  air  compressors,  hoists, 
derricks,  pumps,  etc,  shall  be  so  located  that  the 
exhausts  are  well  away  from  combustible  materials. 
Where  the  exhausts  are  pipes  to  outside  the  building 
under  construction,  a  clearance  of  at  least  150  mm  shall 
be  maintained  between  such  piping  and  combustible 
material. 

9.19.4  Earthing/grounding  of  electrically  powered 
equipment/tools  shall  be  ensured.  Also  all  electric 
powered  equipment  should  be  switched  off  from  mains, 
after  completion  of  day’s  job. 


10  SAFETY  IN  DEMOLITION  OF  BUILDINGS 

10.1  The  safety  requirements  for  carrying  out 
demolition/dismantling  work  shall  be  as  given  in  10.2 
to  10.15. 

10.2  Planning 

Before  beginning  the  actual  work  of  demolition  a 
careful  study  shall  be  made  of  the  structure  which  is  to 
be  pulled  down  and  also  of  all  its  surroundings.  This 
shall,  in  particular,  include  study  of  the  manner  in  which 
the  various  parts  of  the  building  to  be  demolished  are 
supported  and  how  far  the  stage  by  stage  demolition 
will  affect  the  safety  of  the  adjoining  structure.  A 
definite  plan  of  procedure  for  the  demolition  work, 
depending  upon  the  manner  in  which  the  loads  of  the 
various  structural  parts  are  supported,  shall  be  prepared 
and  approved  by  the  engineer-in-charge  and  this  shall 
be  followed  as  closely  as  possible,  in  actual  execution 
of  the  demolition  work.  Before  the  commencement  of 
each  stage  of  demolition,  the  foreman  shall  brief  the 
workers  in  detail  regarding  the  safety  aspects  to  be  kept 
in  view. 

It  should  be  ensured  that  the  demolition  operations  do 
not,  at  any  stage,  and  endanger  the  safety  of  the 
adjoining  buildings.  Moreover,  the  nuisance  effect  of 
the  demolishing  work  on  the  use  of  the  adjacent 
buildings  should  be  kept  to  the  minimum. 

No  structure  or  part  of  the  structure  or  any  floor  or 
temporary  support  or  scaffold,  side  wall  or  any  device 
for  equipment  shall  be  loaded  in  excess  of  the  safe 
carrying  capacity,  in  its  then  existing  condition. 

Electrical  installations  for  demolition  sites  shall  be  in 
accordance  with  12  of  Part  8  ‘Building  Services, 
Section  2  Electrical  and  Allied  Installations’  of  the 
Code. 

10.3  Precautions  Prior  to  Demolition 

10.3.1  On  every  demolition  job,  danger  signs  shall  be 
conspicuously  posted  all  around  the  structure  and  all 
doors  and  openings  giving  access  to  the  structure  shall 
be  kept  barricaded  or  manned  except  during  the  actual 
passage  of  workers  or  equipment.  Flowever,  provisions 
shall  be  made  for  at  least  two  independent  exits  for 
escape  of  workers  during  any  emergency. 

10.3.2  During  nights,  red  lights  shall  be  placed  on  or 
about  all  the  barricades. 

10.3.3  Where  in  any  work  of  demolition  it  is  imperative, 
because  of  danger  existing,  to  ensure  that  no 
unauthorized  person  shall  enter  the  site  of  demolition 
during  the  outside  hours;  a  watchman  should  be 
employed.  In  addition  to  watching  the  site  he  shall  also 
be  responsible  for  maintaining  all  notices,  lights  and 
barricades. 


52 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


10.3.4  All  the  necessary  safety  appliances  shall  be 
issued  to  the  workers  and  their  use  explained.  It  shall 
be  ensured  that  the  workers  are  using  all  the  safety 
appliances  while  at  work. 

10.3.5  The  power  on  all  electrical  service  lines  shall 
be  shut  off  and  all  such  lines  cut  or  disconnected  at  or 
outside  the  property  line,  before  the  demolition  work 
is  started.  Prior  to  cutting  of  such  lines,  the  necessary 
approval  shall  be  obtained  from  the  electrical 
authorities  concerned.  The  only  exception  will  be  any 
power  lines  required  for  demolition  work  itself. 

10.3.6  All  gas,  water  steam  and  other  service  lines  shall 
be  shut  off  and  capped  or  otherwise  controlled  at  or 
outside  the  building  line,  before  demolition  work  is 
started. 

10.3.7  All  the  mains  and  meters  of  the  building  shall 
be  removed  or  protected  from  damage. 

10.3.8  If  a  structure  to  be  demolished  has  been  partially 
wrecked  by  fire,  explosion  or  other  catastrophe,  the 
walls  and  damaged  roofs  shall  be  shored  or  braced 
suitably. 

10.3.9  Protection  of  the  Public 

10.3.9.1  Safety  distances  to  ensure  safety  of  the  public 
shall  be  clearly  marked  and  prominently  sign  posted. 
Every  sidewalk  or  road  adjacent  to  the  work  shall  be 
closed  or  protected.  All  main  roads,  which  are  open  to 
the  public,  shall  be  kept  open  to  the  public  clear  and 
unobstructed  at  all  times.  Diversions  for  pedestrians 
shall  be  constructed,  where  necessary  for  safety. 

10.3.9.2  If  the  structure  to  be  demolished  is  more  than 
two  storeyed  or  7.5  m  high,  measured  from  the  side 
walk  or  street  which  cannot  be  closed  or  safely  diverted, 
and  the  horizontal  distance  from  the  inside  of  the 
sidewalk  to  the  structure  is  4.5  m  or  less,  a  substantial 
sidewalk  shed  shall  be  constructed  over  the  entire  length 
of  the  sidewalk  adjacent  to  the  structure,  of  sufficient 
width  with  a  view  to  accommodating  the  pedestrian 
traffic  without  causing  congestion.  The  side  walk  shed 
shall  be  lighted  sufficiently  to  ensure  safety  at  all  times. 
For  detailed  information  reference  may  be  made  to  good 
practice  [7(51)]. 

A  toe  board  of  at  least  1  m  high  above  the  roof  of  the 
shed  shall  be  provided  on  the  outside  edge  and  ends  of 
the  sidewalk  shed.  Such  boards  may  be  vertical  or 
inclined  outward  at  not  more  than  45°. 

Except  where  the  roof  of  a  sidewalk  shed  solidly  abuts 
the  structure,  the  face  of  the  sidewalk  shed  towards  the 
building  shall  be  completely  closed  by  providing 
sheeting/planking  to  prevent  falling  material  from 
penetrating  into  the  shed. 

The  roof  of  sidewalk  sheds  shall  be  capable  of 


sustaining  a  load  of  73  N/mm2.  Only  in  exceptional 
cases,  say  due  to  lack  of  other  space,  the  storing  of 
material  on  a  sidewalk  shed  may  be  permitted  in  which 
case  the  shed  shall  be  designed  for  a  load  of  146  N/mm2. 
Roof  of  sidewalk  shed  shall  be  designed  taking  into 
account  the  impact  of  the  falling  debris.  By  frequent 
removal  of  loads  it  shall  be  ensured  that  the  maximum 
load,  at  any  time,  on  the  roof  of  work  shed  is  not  more 
than  6  000  N/m2.  The  height  of  sidewalk  shed  shall  be 
such  as  to  give  a  minimum  clearance  of  2.4  m. 

Sidewalk  shed  opening,  for  loading  purposes,  shall  be 
kept  closed  at  all  time  except  during  actual  loading 
operations. 

The  deck  flooring  of  the  sidewalk  shed  shall  consist  of 
plank  of  not  less  than  50  mm  in  thickness  closely  laid 
and  deck  made  watertight.  All  members  of  the  shed 
shall  be  adequately  braced  and  connected  to  resist 
displacement  of  members  or  distortion  of  framework. 

10.3.9.3  When  the  horizontal  distance  from  the  inside 
of  the  sidewalk  to  the  structure  is  more  than  4.5  m  and 
less  than  7.5  m,  a  sidewalk  shed  or  fence  or  a  substantial 
railing  shall  be  constructed  on  the  inside  of  the  sidewalk 
or  roadway  along  the  entire  length  of  the  demolition 
side  of  the  property  with  movable  bars  as  may  be 
necessary  for  the  proper  execution  of  the  work. 

NOTE  —  For  guidance  on  management  of  pedestrians/cyclists/ 
vehicles  near  road  construction  sites,  reference  may  be  made 
to  IRC  SP  55  :  2014  ‘Guidelines  on  traffic  management  in  work 
zones’. 

10.4  Precautions  During  Demolition 

10.4.1  Prior  to  commencement  of  work,  all  material  of 
fragile  nature  like  glass  shall  be  removed. 

10.4.2  All  openings  shall  be  boarded  up. 

10.4.3  Dust  shall  be  controlled  by  suitable  means  to 
prevent  harm  to  workers. 

10.4.4  Stacking  of  materials  or  debris  shall  be  within 
safe  limits  of  the  structural  member.  Additional 
supports,  where  necessary,  shall  be  given. 

10.4.5  Adequate  natural  or  artificial  lighting  and 
ventilation  shall  be  provided  for  the  workers. 

10.5  Sequence  of  Demolition  Operations 

10.5.1  The  demolition  work  shall  be  proceeded  with  in 
such  a  way  that, 

a)  it  causes  the  least  damage  and  nuisance  to  the 
adjoining  building  and  the  members  of  the 
public;  and 

b)  it  satisfies  all  safety  requirements  to  avoid  any 
accidents. 

10.5.2  All  existing  fixtures  required  during  demolition 


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operations  shall  be  well  protected  with  substantial 
covering  to  the  entire  satisfaction  of  the  rules  and 
regulations  of  the  undertakings  or  they  shall  be 
temporarily  relocated. 

10.5.3  Before  demolition  work  is  started,  glazed  sash, 
glazed  doors  and  windows,  etc,  shall  be  removed.  All 
fragile  and  loose  fixtures  shall  be  removed.  The  lath 
and  all  loose  plaster  shall  be  stripped  off  throughout 
the  entire  building.  This  is  advantageous  because  it 
reduces  glass  breakage  and  also  eliminates  a  large 
amount  of  dust  producing  material  before  more 
substantial  parts  of  the  buildings  are  removed. 

10.5.4  All  well  openings  which  extend  down  to  floor 
level  shall  be  barricaded  to  a  height  of  not  less  than 
one  metre  above  the  floor  level.  This  provision  shall 
not  apply  to  the  ground  level  floor. 

10.5.5  All  floor  openings  and  shafts  not  used  for 
material  chutes  shall  be  floored  over  and  be  enclosed 
with  guard  rails  and  toe  boards. 

10.5.6  The  demolition  shall  always  proceed 
systematically  storey  by  storey  in  descending  order.  All 
work  in  the  upper  floor  shall  be  completed  and 
approved  by  the  engineer-in-charge  prior  to  disturbance 
to  any  supporting  member  on  the  lower  floor. 
Demolition  of  the  structure  in  sections  may  be  permitted 
in  exceptional  cases,  if  proper  precautions  are  ensured 
to  prevent  injuries  to  persons  and  damage  to  property. 

10.6  Walls 

10.6.1  While  walls  of  sections  of  masonry  are  being 
demolished,  it  shall  be  ensured  that  they  are  not  allowed 
to  fall  as  single  mass  upon  the  floors  of  the  building 
that  are  being  demolished  so  as  to  exceed  the  safe 
carrying  capacity  of  the  floors.  Overloading  of  floors 
shall  be  prevented  by  removing  the  accumulating  debris 
through  chutes  or  by  other  means  immediately.  The 
floor  shall  be  inspected  by  the  engineer-in-charge  before 
undertaking  demolition  work  and  if  the  same  is  found 
to  be  incapable  to  carry  the  load  of  the  debris,  necessary 
additional  precautions  shall  be  taken  so  as  to  prevent 
any  possible  unexpected  collapse  of  the  floor. 

10.6.2  Walls  shall  be  removed  part  by  part.  Stages  shall 
be  provided  for  the  men  to  work  on  if  the  walls  are  less 
than  one  and  a  half  brick  thick  and  dangerous  to  work 
by  standing  over  them. 

10.6.3  Adequate  lateral  bracing  shall  be  provided  for 
walls  which  are  unsound.  For  detailed  information 
reference  may  be  made  to  good  practice  [7(51)]. 

10.7  Flooring 

10.7.1  Prior  to  removal  of  masonry  or  concrete  floor 
adequate  support  centering  shall  be  provided. 


10.7.2  When  floors  are  being  removed,  no  worker  or 
person  shall  be  allowed  to  work  in  the  area,  directly 
underneath  and  such  area  shall  be  barricaded  to  prevent 
access  to  it. 

10.7.3  Planks  of  sufficient  strength  shall  be  provided 
to  give  workers  firm  support  to  guard  against  any 
unexpected  floor  collapse. 

10.8  Demolition  of  Steel  Structures 

10.8.1  When  a  derrick  is  used,  care  shall  be  taken  to 
see  that  the  floor  on  which  it  is  supported  is  amply 
strong  for  the  loading  so  imposed.  If  necessary  heavy 
planking  shall  be  used  to  distribute  the  load  to  floor 
beam  and  girders. 

10.8.2  Overloading  of  equipment  shall  not  be  allowed. 

10.8.3  Tag  lines  shall  be  used  on  all  materials  being 
lowered  or  hoisted  up  and  a  standard  signal  system  shall 
be  used  and  the  workers  instructed  on  the  signals. 

10.8.4  No  person  shall  be  permitted  to  ride  the  load 
line. 

10.8.5  No  beams  shall  be  cut  until  precautions  have 
been  taken  to  prevent  it  from  swinging  freely  and 
possibly  striking  any  worker  or  equipment  or  to  any 
part  of  the  structure  being  demolished. 

10.8.6  All  structural  steel  members  shall  be  lowered 
from  the  building  and  shall  not  be  allowed  to  drop. 

10.9  Catch  Platform 

10.9.1  In  demolition  of  exterior  walls  of  multistorey 
structures,  catch  platform  of  sufficient  strength  to 
prevent  injuries  to  workers  below  and  public  shall  be 
provided,  when  the  external  walls  are  more  than  20  m 
in  height. 

10.9.2  Such  catch  platform  shall  be  constructed  and 
maintained  not  more  than  3  storeys  below  the  storey 
from  which  exterior  wall  is  being  demolished.  When 
demolition  has  progressed  to  within  3  storeys  of  ground 
level,  catch  platform  will  not  be  considered  necessary. 

10.9.3  Catch  platform  shall  be  capable  of  sustaining  a 
live  load  of  not  less  than  6  100  N/m2. 

10.9.4  Materials  shall  not  be  dumped  on  the  catch 
platform  nor  shall  they  be  used  for  storage  of  materials. 

10.10  Stairs,  Passageways  and  Ladders 

10.10.1  Stairs  with  railings,  passageways  and  ladders 
shall  be  left  in  place  as  long  as  possible  and  maintained 
in  a  safe  condition. 

10.10.2  All  ladders  shall  be  secured  against,  slipping 
out  at  the  bottom  and  against  movement  in  any  direction 
at  the  top. 


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10.11  Mechanical  Demolition 

When  demolition  is  to  be  performed  by  mechanical 
devices,  such  as  weight  ball  and  power  shovels,  the 
following  additional  precautions  may  be  observed: 

a)  The  area  shall  be  barricaded  for  a  minimum 
distance  of  1  lA  times  the  height  of  the  wall; 

b)  While  the  mechanical  device  is  in  operation, 
no  worker  shall  be  allowed  to  enter  the 
building  being  demolished; 

c)  The  device  shall  be  so  located  as  to  avoid 
falling  debris;  and 

d)  The  mechanical  device,  when  being  used,  shall 
not  cause  any  damage  to  adjacent  structure, 
power  line,  etc. 

10.12  Demolition  of  Certain  Special  Types  and 
Elements  of  Structures 

10.12.1  Roof  Trusses 

If  a  building  has  a  pitched  roof,  the  structure  should  be 
removed  to  wall  plate  level  by  hand  methods.  Sufficient 
purlins  and  bracing  should  be  retained  to  ensure  stability 
of  the  remaining  roof  trusses  while  each  individual  truss 
is  removed  progressively. 

10.12.1.1  Temporary  bracing  should  be  added,  where 
necessary,  to  maintain  stability.  The  end  frame  opposite 
to  the  end  where  dismantling  is  commenced,  or  a 
convenient  intermediate  frame  should  be  independently 
and  securely  guyed  in  both  directions  before  work 
starts. 

10.12.1.2  On  no  account  should  the  bottom  tie  of  roof 
trusses  be  cut  until  the  principal  rafters  are  prevented 
from  making  outward  movement. 

10.12.1.3  Adequate  hoisting  gears  suitable  for  the  loads 
shall  be  provided.  If  during  demolition  any  thing  is  to 
be  put  on  the  floor  below  the  level  of  the  truss,  it  shall 
be  ensured  that  the  floor  is  capable  of  taking  the  load. 

10.12.2  Heavy  Floor  Beams 

Heavy  baulks  of  timber  and  steel  beams  should  be 
supported  before  cutting  at  the  extremities  and  should 
then  be  lowered  gently  to  a  safe  working  place. 

10.12.3  Jack  Arches 

Where  tie  rods  are  present  between  main  supporting 
beams,  these  should  not  be  cut  until  after  the  arch  or 
series  of  arches  in  the  floor  have  been  removed.  The 
floor  should  be  demolished  in  strips  parallel  to  the  span 
of  the  arch  rings  (at  right  angles  to  the  main  floor 
beams). 

10.12.4  Brick  Arches 

Expert  advice  should  be  obtained  and,  at  all  stages  of 
the  demolition,  the  closest  supervision  should  be  given 


by  persons  fully  experienced  and  conversant  in  the  type 
of  work  to  ensure  that  the  structure  is  stable  at  all  times. 

However,  the  following  points  may  be  kept  in  view: 

a)  On  no  account  should  the  restraining  influence 
of  the  abutments  be  removed  before  the  dead 
load  of  the  spandrel  fill  and  the  arch  rings  are 
removed. 

b)  A  single  span  arch  can  be  demolished  by  hand 
by  cutting  narrow  segments  progressively 
from  each  springing  parallel  to  the  span  of  the 
arch,  until  the  width  of  the  arch  has  been 
reduced  to  a  minimum  which  can  then  be 
collapsed. 

c)  Where  deliberate  collapse  is  feasible,  the 
crown  may  be  broken  by  the  demolition  ball 
method  working  progressively  from  edges  to 
the  centre. 

d)  Collapse  of  the  structure  can  be  affected  in 
one  action  by  the  use  of  explosives.  Charges 
should  be  inserted  into  bore  holes  drilled  in 
both  arch  and  abutments. 

e)  In  multi-span  arches,  before  individual  arches 
are  removed,  lateral  restraint  should  be 
provided  at  the  springing  level.  Demolition 
may  then  proceed  as  for  single  span;  where 
explosives  are  used  it  is  preferable  to  ensure 
the  collapse  of  the  whole  structure  in  one 
operation  to  obviate  the  chance  of  leaving 
unstable  portion  standing. 

10.12.5  Cantilever  (Not  Part  of  a  Framed  Structure) 

Canopies,  cornices,  staircases  and  balconies  should  be 
demolished  or  supported  before  tailing  down  load  is 
removed. 

10.12.6  In-situ  Reinforced  Concrete 

Before  commencing  demolition,  the  nature  and 
condition  of  the  concrete,  the  condition  and  position 
of  reinforcement,  and  the  possibility  of  lack  of 
continuity  of  reinforcement  should  be  ascertained. 

Demolition  should  be  commenced  by  removing 
partitions  and  external  non-load  bearing  cladding. 

10.12.6.1  Reinforced  concrete  beams 

A  supporting  rope  should  be  attached  to  the  beam.  Then 
the  concrete  should  be  removed  from  both  ends  by 
pneumatic  drill  and  the  reinforcement  exposed.  The 
reinforcement  should  then  be  cut  in  such  a  way  as  to 
allow  the  beam  to  be  lowered  under  control  to  the  floor. 

10.12.6.2  Reinforced  concrete  columns 

The  reinforcement  should  be  exposed  at  the  base  after 
restraining  wire  guy  ropes  have  been  placed  round  the 
member  at  the  top.  The  reinforcement  should  then  be 


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55 


cut  ill  such  a  way  as  to  allow  it  to  be  pulled  down  to  the 
floor  under  control. 

10.12.6.3  Reinforced  concrete  walls 

These  should  be  cut  into  strips  and  demolished  as  for 
columns. 

10.12.6.4  Suspended  floors  and  roofs 

The  slab  should  be  cut  into  strips  parallel  to  the  main 
reinforcement  and  demolished  strip  by  strip.  Where 
ribbed  construction  has  been  used,  the  principle  of 
design  and  method  of  construction  should  be 
determined  before  demolition  is  commenced.  Care 
should  be  taken  not  to  cut  the  ribs  inadvertently. 

10.12.7  Precast  Reinforced  Concrete 

Due  precautions  shall  be  taken  to  avoid  toppling  over 
of  prefabricated  units  or  any  other  part  of  the  structure 
and  whenever  necessary  temporary  supports  shall  be 
provided. 

10.12.8  Prestressed  Reinforced  Concrete 

Before  commencing  of  the  demolition  work,  advice  of 
an  engineering  expert  in  such  demolition  shall  be 
obtained  and  followed. 

10.13  Lowering,  Removal  and  Disposal  of  Materials 

10.13.1  Dismantled  materials  may  be  thrown  to  the 
ground  only  after  taking  adequate  precautions.  The 
material  shall  preferably  be  dumped  inside  the  building. 
Normally  such  materials  shall  be  lowered  to  the  ground 
or  to  the  top  of  the  sidewalk  shed  where  provided  by 
means  of  ropes  or  suitable  tackles. 

10.13.2  Through  Chutes 

10.13.2.1  Wooden  or  metal  chutes  may  be  provided 
for  removal  of  materials.  The  chutes  shall  preferably 
be  provided  at  the  centre  of  the  building  for  efficient 
disposal  of  debris. 

10.13.2.2  Chutes,  if  provided  at  an  angle  of  more  than 
45°  from  the  horizontal,  shall  be  entirely  enclosed  on 
all  the  four  sides,  except  for  opening  at  or  about  the 
floor  level  for  receiving  the  materials. 

10.13.2.3  To  prevent  the  descending  material  attaining 
a  dangerous  speed,  chute  shall  not  extend  in  an 
unbroken  line  for  more  than  two  storeys.  A  gate  or  stop 
shall  be  provided  with  suitable  means  for  closing  at 
the  bottom  of  each  chute  to  stop  the  flow  of  materials. 

10.13.2.4  Any  opening  into  which  workers  dump  debris 
at  the  top  of  chute  shall  be  guarded  by  a  substantial 
guard  rail  extending  at  least  one  metre  above  the  level 
of  the  floor  or  other  surface  on  which  men  stand  to 
dump  the  materials  into  the  chute. 

10.13.2.5  A  toe  board  or  bumper,  not  less  than  50  mm 


thick  and  150  mm  high  shall  be  provided  at  each  chute 
openings,  if  the  material  is  dumped  from  the  wheel 
barrows.  Any  space  between  the  chute  and  the  edge  of 
the  opening  in  the  floor  through  which  it  passes  shall 
be  solidly  planked  over. 

10.13.3  Through  Holes  in  the  Floors 

10.13.3.1  Debris  may  also  be  dropped  through  holes 
in  the  floor  without  the  use  of  chutes.  In  such  a  case  the 
total  area  of  the  hole  cut  in  any  intermediate  floor,  one 
which  lies  between  floor  that  is  being  demolished  and 
the  storage  floor  shall  not  exceed  25  percent  of  such 
floor  area.  It  shall  be  ensured  that  the  storage  floor  is 
of  adequate  strength  to  withstand  the  impact  of  the 
falling  material. 

10.13.3.2  All  intermediate  floor  openings  for  passage 
of  materials  shall  be  completely  enclosed  with 
barricades  or  guard  rails  not  less  than  one  metre  high 
and  at  a  distance  of  not  less  than  1  m  from  the  edge  of 
general  opening.  No  barricades  or  guard  rails  shall  be 
removed  until  the  storey  immediately  above  has  been 
demolished  down  to  the  floor  line  and  all  debris  cleared 
from  the  floor. 

10.13.3.3  When  the  cutting  of  a  hole  in  an  intermediate 
floor  between  the  storage  floor  and  the  floor  which  is 
being  demolished  makes  the  intermediate  floor  or  any 
portion  of  it  unsafe,  then  such  intermediate  floor  shall 
be  properly  shored.  It  shall  also  be  ensured  that  the 
supporting  walls  are  not  kept  without  adequate  lateral 
restraints. 

10.13.4  Removal  of  Materials 

10.13.4.1  As  demolition  work  proceeds,  the  released 
serviceable  materials  of  different  types  shall  be 
separated  from  the  unserviceable  lot  (hereinafter  called 
'Malba')  at  suitable  time  intervals  and  properly  stocked 
clear  of  the  spots  where  demolition  work  is  being  done. 

10.13.4.2  Th q  Malba  obtained  during  demolition  shall 
be  collected  in  well-formed  heaps  at  properly  selected 
places,  keeping  in  view  safe  conditions  for  workers  in 
the  area.  The  height  of  each  Malba  heap  shall  be  limited 
to  ensure  its  toppling  over  or  otherwise  endangering 
the  safety  of  workers  or  passersby. 

10.13.4.3  The  Malba  shall  be  removed  from  the 
demolition  site  to  a  location  as  required  by  the  local 
civil  authority.  Depending  on  the  space  available  at  the 
demolition  site,  this  operation  of  conveying  Malba  to 
its  final  disposal  location  may  have  to  be  carried  out  a 
number  of  times  during  the  demolition  work.  In  any 
case,  the  demolition  work  shall  not  be  considered  as 
completed  and  the  area  declared  fit  for  further 
occupation  till  all  the  Malba  has  been  carried  to  its 
final  disposal  location  and  the  demolition  areas  tidied 
up. 


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10.13.4.4  Materials  which  are  likely  to  cause  dust 
nuisance  or  undue  environmental  pollution  in  any  other 
way,  shall  be  removed  from  the  site  at  the  earliest  and 
till  then  they  shall  be  suitably  covered.  Such  materials 
shall  be  covered  during  transportation  also. 

10.13.4.5  Following  other  requirements  should  also  be 
met: 

a)  Glass  and  steel  should  be  dumped  or  buried 
separately  to  prevent  injury. 

b)  Workman  should  be  provided  with  suitable 
protective  gears  for  personal  safety  during 
works,  like  safety  helmets,  boots,  hand  gloves, 
goggles,  special  attire,  etc. 

c)  Work  of  removal  of  debris  should  be  carried 
out  during  day.  In  case  of  poor  visibility 
artificial  light  may  be  provided. 

d)  Debris  should  first  be  removed  from  top.  Early 
removal  from  bottom  or  sides  of  dump  may 
cause  collapse  of  debris,  causing  injuries. 

10.14  Miscellaneous 

10.14.1  No  demolition  work  should  be  carried  out 
during  night  as  far  as  possible,  especially  when  the 
structure  to  be  demolished  is  in  an  inhabited  area.  If 
such  night  work  has  to  be  done,  additional  precautions 
by  way  of  additional  red  warning  signals,  working  lights 
and  watchmen,  shall  be  provided  to  avoid  any  injury 
to  workers  and  public.  Demolition  work  shall  not  be 
carried  out  during  storm  and  heavy  rain. 

10.14.2  Warning  devices  shall  be  installed  in  the  area 
to  warn  the  workers  in  case  of  any  danger. 

10.14.3  Safety  devices  like  industrial  safety  helmets 
conforming  to  the  accepted  standards  [7(28)]  and 
goggles  made  of  celluloid  lens,  shall  be  issued  to  the 
workers.  Foreman-in-charge  of  the  work  areas  shall 
ensure  that  all  the  workers  are  wearing  the  safety 
devices  before  commencing  any  work. 

10.14.4  Construction  sheds  and  tool  boxes  shall  be  so 
located  as  to  protect  workers  from  injuries  from  the 
falling  debris. 

10.14.5  Where  there  is  a  likelihood  of  injuries  to  hands 
of  workers  when  demolishing  RCC,  steel  structures,  etc, 
gloves  of  suitable  materials  shall  be  worn  by  workers. 

10.14.6  Sufficient  protection  by  way  of  both  overhead 
cover  and  screens  shall  be  provided  to  prevent  injuries 
to  the  workers  and  the  public. 

10.14.7  Safety  belts  or  ropes  shall  be  used  by  workers 
when  working  at  higher  levels. 

10.14.8  Grading  of  Plot 

When  a  building  has  been  demolished  and  no  building 
operation  has  been  projected  or  approved,  the  vacant 


plot  shall  be  filled,  graded  and  maintained  in  conformity 
to  the  established  street  grades  at  kerb  level.  The  plot 
shall  be  maintained  free  from  the  accumulation  of 
rubbish  and  all  other  unsafe  and  hazardous  conditions 
which  endangers  the  life  or  health  of  the  public;  and 
provisions  shall  be  made  to  prevent  the  accumulation 
of  water  or  damage  to  any  foundations  on  the  premises 
or  the  adjoining  property. 

10.15  First-Aid 

10.15.1  A  copy  of  all  pertinent  regulations  and  notices 
concerning  accidents,  injury  and  first-aid  shall  be 
prominently  exhibited  at  the  work  site. 

10.15.2  Depending  on  the  scope  and  nature  of  the  work, 
a  person,  qualified  in  first-aid  shall  be  available  at  work 
site  to  render  and  direct  first-aid  to  casualties.  He  shall 
maintain  a  list  of  individuals  qualified  to  serve  in  first- 
aid  work.  Enough  first-aid  kit,  including  a  stretcher  and 
a  cot  with  accessories  shall  be  provided  at  site.  A 
telephone  may  be  provided  to  first-aid  assistant  with 
telephone  numbers  of  the  hospitals  prominently 
displayed. 

Complete  reports  of  all  accidents  and  action  taken 
thereon  shall  be  forwarded  to  the  competent  authorities. 

SECTION  5  REPAIRS,  RETROFITTING  AND 
STRENGTHENING  OF  BUILDINGS 

11  MAINTENANCE  MANAGEMENT 

Maintenance  management  of  building  is  the  art  of 
preserving  over  a  long  period  what  has  been 
constructed.  Whereas  construction  stage  lasts  for  a  short 
period,  maintenance  continues  for  comparatively  very 
large  period  during  the  useful  life  of  building. 
Inadequate  or  improper  maintenance  adversely  affects 
the  environment  in  which  people  work,  thus  affecting 
the  overall  output.  In  the  post  construction  stage  the 
day  to  day  maintenance  or  upkeep  of  the  building  shall 
certainly  delay  the  decay  of  the  building  structure. 
Though  the  building  may  be  designed  to  be  very  durable 
it  needs  maintenance  to  keep  it  in  good  condition.  The 
maintenance  management  of  buildings  shall  be  done 
in  accordance  with  Part  12  ‘Asset  and  Facility 
Management’  of  the  Code. 

12  PREVENTION  OF  CRACKS 

12.1  Cracks  in  buildings  are  of  common  occurrence.  A 
building  component  develops  cracks  whenever  stress 
in  the  component  exceeds  its  strength.  Stress  in  a 
building  component  could  be  caused  by  externally 
applied  forces,  such  as  dead,  imposed,  wind  or  seismic 
loads,  or  foundation  settlement  or  it  could  be  induced 
internally  due  to  thermal  movements,  moisture  changes, 
chemical  action,  etc. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


57 


12.2  Cracks  could  be  broadly  classified  as  structural 
or  non-structural.  Structural  cracks  are  those  which  are 
due  to  incorrect  design,  faulty  construction  or 
overloading  and  these  may  endanger  the  safety  of  a 
building.  Extensive  cracking  of  an  RCC  beam  is  an 
instance  of  structural  cracking.  Non-structural  cracks 
are  mostly  due  to  internally  induced  stresses  in  building 
materials  and  these  generally  do  not  directly  result  in 
structural  weakening.  In  course  of  time,  however, 
sometime  non-structural  cracks  may,  because  of 
penetration  of  moisture  through  cracks  or  weathering 
action,  result  in  corrosion  of  reinforcement  and  thus 
may  render  the  structure  unsafe.  Vertical  cracks  in  a 
long  compound  wall  due  to  shrinkage  or  thermal 
movement  is  an  instance  of  non-structural  cracking. 
Non-structural  cracks,  normally  do  not  endanger  the 
safety  of  a  building,  but  may  look  unsightly,  or  may 
create  an  impression  of  faulty  work  or  may  give  a 
feeling  of  instability.  In  some  situations,  cracks  may, 
because  of  penetration  of  moisture  through  them,  spoil 
the  internal  finish,  thus  adding  to  cost  of  maintenance. 
It  is,  therefore,  necessary  to  adopt  measures  of 
prevention  or  minimization  of  these  cracks. 

12.3  For  complete  details  on  causes  and  prevention  of 
non-structural  cracks,  reference  shall  be  made  to  good 
practice  SP  25:1984  ‘Handbook  on  causes  and 
prevention  of  cracks  in  buildings’. 

13  REPAIRS  AND  SEISMIC  STRENGTHENING 
OF  BUILDINGS 

13.1  General  Principles  and  Concepts 

13.1.1  Non-structural/Architectural  Repairs 

13.1.1.1  The  buildings  affected  by  earthquake  may 
suffer  both  non-structural  and  structural  damages.  Non- 
structural  repairs  may  cover  the  damages  to  civil  and 
electrical  items,  including  the  services  in  the  building. 
Repairs  to  non-structural  components  need  to  be  taken 
up  after  the  structural  repairs  and  retrofitting  work  are 
carried  out.  Care  should  be  taken  about  the  connection 
details  of  architectural  components  to  the  main 
structural  components  to  ensure  their  stability. 

13.1.1.2  Non-structural  and  architectural  components 
get  easily  affected/  dislocated  during  the  earthquake. 
These  repairs  involve  one  or  more  of  the  following: 

a)  Patching  up  of  defects  such  as  cracks  and  fall 
of  plaster; 

b)  Repairing  doors,  windows,  replacement  of 
glass  panes; 

c)  Checking  and  repairing  electric  conduits/ 
wiring; 

d)  Checking  and  repairing  gas  pipes,  water  pipes 
and  plumbing  services; 

e)  Rebuilding  non-structural  walls,  smoke 


chimneys,  parapet  walls,  etc; 

f)  Replastering  of  walls,  as  required; 

g)  Rearranging  disturbed  roofing  tiles; 

h)  Relaying  cracked  flooring  at  ground  level;  and 

j)  Redecoration  -  white  washing,  painting,  etc. 

The  architectural  repairs  as  stated  above  do  not  restore 
the  original  structural  strength  of  structural  components 
in  the  building  and  any  attempt  to  carry  out  only  repairs 
to  architectural/non-structural  elements,  neglecting  the 
required  structural  repairs,  may  have  serious 
implications  on  the  safety  of  the  building.  The  damage 
would  be  more  severe  in  the  event  of  the  building  being 
shaken  by  a  similar  shock  because  original  energy 
absorption  capacity  of  the  building  would  have  been 
reduced. 

13.1.2  Structural  Repairs/Restoration 

13.1.2.1  Prior  to  taking  up  of  the  structural  repairs  for 
restoration  of  original  strength  and  any  strengthening 
measures,  it  is  necessary  to  conduct  detailed  damage 
assessment  to  determine, 

a)  the  structural  condition  of  the  building  to 
decide  whether  a  structure  is  amenable  for 
repair;  whether  continued  occupation  is 
permitted;  to  decide  the  structure  as  a  whole 
or  a  part  require  demolition,  if  considered 
dangerous; 

b)  if  the  structure  is  considered  amenable  for 
repair  then  detailed  damage  assessment  of  the 
individual  structural  components  (mapping  of 
the  crack  pattern,  distress  location;  crushed 
concrete,  reinforcement  bending/yielding, 
etc).  Non-destructive  testing  techniques  could 
be  employed  to  detennine  the  residual  strength 
of  the  members;  and 

c)  to  work  out  the  details  of  temporary  supporting 
arrangement  of  the  distressed  members  so  that 
they  do  not  undergo  further  distress  due  to 
gravity  loads. 

13.1.2.2  After  the  assessment  of  the  damage  of 
individual  structural  elements,  appropriate  repair 
methods  are  to  be  carried  out  component-wise 
depending  on  the  extent  of  damage.  The  restoration 
work  may  consist  of  the  following: 

a)  Removal  of  portions  of  cracked  masonry  walls 
and  piers  and  rebuilding  them  in  richer  mortar. 
Use  of  non-shrinking  mortar  will  be 
preferable. 

b)  Addition  of  reinforcing  mesh  on  both  faces 
of  the  cracked  wall,  holding  it  to  the  wall 
through  spikes  or  bolts  and  then  covering  it, 
suitably,  with  cement  mortar  or  micro¬ 
concrete  (maximum  size  of  aggregate  limited 


58 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


to  6  mm  or  less  as  suitable),  and  may  be  with 
use  of  micro-reinforcement  as  fibre  or  ferro- 
cement. 

c)  Injecting  cement,  polymer-cement  mixture  or 
epoxy  materials,  which  are  strong  in  tension, 
into  the  cracks  in  walls. 

d)  The  cracked  reinforced  concrete  elements 
may  be  repaired  by  epoxy  grouting  and  could 
be  strengthened  by  epoxy  or  polymer  mortar 
application  like  shotcreting,  jacketing,  etc. 

NOTE  —  In  mortar  for  masonry  or  plaster,  fibres  can  be  used. 

13.1.3  Seismic  Strengthening 

The  main  purpose  of  the  seismic  strengthening  is  to 
upgrade  the  seismic  resistance  of  a  damaged  building 
while  repairing  so  that  it  becomes  safer  under  future 
earthquake  occurrences.  This  work  may  involve  some 
of  the  following  actions: 

a)  Increasing  the  lateral  strength  in  one  or  both 
directions  by  increasing  column  and  wall 
areas  or  the  number  of  walls  and  columns. 

b)  Giving  unity  to  the  structure,  by  providing  a 
proper  connection  between  its  resisting 
elements,  in  such  a  way  that  inertia  forces 
generated  by  the  vibration  of  the  building  can 
be  transmitted  to  the  members  that  have  the 
ability  to  resist  them.  Typical  important 
aspects  are  the  connections  between  roofs  or 
floors  and  walls,  between  intersecting  walls 
and  between  walls  and  foundations. 

c)  Eliminating  features  that  are  sources  of 
weakness  or  that  produce  concentration  of 
stresses  in  some  members.  Asymmetrical 
plan  distribution  of  resisting  members,  abrupt 
changes  of  stiffness  from  one  floor  to  the 
other,  concentration  of  large  masses  and  large 
openings  in  walls  without  a  proper  peripheral 
reinforcement  are  examples  of  defects  of  this 
kind. 

d)  Avoiding  the  possibility  of  brittle  modes  of 
failure  by  proper  reinforcement  and 
connection  of  resisting  members. 

13.1.4  Seismic  Retrofitting 

Many  existing  buildings  do  not  meet  the  seismic 
strength  requirements  of  present  earthquake  codes  due 
to  original  structural  inadequacies  and  material 
degradation  due  to  time  or  alterations  carried  out 
during  use  over  the  years.  Their  earthquake  resistance 
can  be  upgraded  to  the  level  of  the  present  day  codes 
by  appropriate  seismic  retrofitting  techniques,  such 
as  mentioned  in  13.1.3. 

13.1.5  Strengthening  or  Retrofititng  Versus 
Reconstruction 

13.1.5.1  Replacement  of  damaged  buildings  or 


existing  unsafe  buildings  by  reconstruction  is, 
generally,  avoided  due  to  a  number  of  reasons,  the 
main  ones  among  them  being, 

a)  higher  cost  than  that  of  strengthening  or 
retrofitting; 

b)  preservation  of  historical  architecture;  and 

c)  maintaining  functional  social  and  cultural 
environment. 

In  most  instances,  however,  the  relative  cost  of 
retrofitting  to  reconstruction  cost  determines  the 
decision.  As  a  thumb  rule,  if  the  cost  of  repair  and 
seismic  strengthening  is  less  than  about  50  percent  of 
the  reconstruction  cost,  the  retrofitting  is  adopted.  This 
may  also  require  less  working  time  and  much  less 
dislocation  in  the  living  style  of  the  population.  On 
the  other  hand  reconstruction  may  offer  the  possibility 
of  modernization  of  the  habitat  and  may  be  preferred 
by  well-to-do  communities. 

13.1.5.2  Cost  wise  the  building  construction  including 
the  seismic  code  provisions  in  the  first  instance,  works 
out  to  be  the  cheaper  in  terms  of  its  own  safety  and 
that  of  the  occupants.  Retrofitting  an  existing 
inadequate  building  may  involve  as  much  as  4  to  5 
times  the  initial  extra  expenditure  required  on  seismic 
resisting  features.  Repair  and  seismic  strengthening 
of  a  damaged  building  may  even  be  5  to  10  times  as 
expensive.  It  is,  therefore,  very  much  safe  as  well  as 
cost-effective  to  construct  earthquake  resistant 
buildings  at  the  initial  stage  itself  according  to  the 
relevant  seismic  IS  codes. 

13.2  For  detailed  guidelines  for  repairs  and  seismic 
strengthening  of  masonry  buildings,  reference  shall 
be  made  to  good  practice  [7(52)]. 

13.3  For  detailed  guidelines  for  improving  earthquake 
resistance  of  low  strength  masonry  buildings, 
reference  shall  be  made  to  good  practice  [7(53)]. 

13.4  For  detailed  guidelines  for  improving  earthquake 
resistance  of  earthen  buildings,  reference  shall  be 
made  to  good  practice  [7(54)]. 

13.5  For  detailed  guidelines  for  seismic  evaluation 
and  strengthening  of  existing  reinforced  concrete 
buildings,  reference  shall  be  made  to  good  practice 
[7(55)]. 

SECTION  6  HABITAT  AND  WELFARE 
REQUIREMENTS  FOR  WORKERS 

14  HABITAT  AND  OTHER  WELFARE 
REQUIREMENTS  FOR  CONSTRUCTION 
WORKERS 

14.1  The  following  aspects  relating  to  habitat  and  other 
welfare  requirements  for  construction  workers  at  site 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


59 


shall  be  met  with,  in  accordance  with  14.2  to  14.16: 

a)  Habitat  site  selection  criteria; 

b)  Area  requirements  for  the  various  facilities  of 
the  habitat; 

c)  Design  of  the  habitat  including  the 
construction  materials; 

d)  Specifications  of  living  area,  height  of  the 
rooms,  windows  and  doors,  ventilation; 

e)  Specification  and  requirements  for  kitchen  and 
other  sanitary  facilities,  such  as  toilets, 
bathrooms,  etc; 

f)  Fire  and  safety  requirements; 

g)  First  aid  and  medical  requirements; 

h)  Creches; 

j)  Habitat  operation  and  maintenance; 

k)  Security; 

m)  Recreational  facilities; 

n)  Waste  management; 

p)  Habitat  inspection  and  monitoring;  and 

q)  Other  facilities. 

The  project  authorities  should,  depending  on  size  of 
the  project,  number  of  workers  employed,  location  of 
the  project,  etc,  provide  these  facilities  for  the  workers. 
They  should  also  decide  the  nature  of  facilities  that 
should  be  provided  at  the  workplace  within  working 
hours. 

14.2  Habitat  Site  Selection  Criteria 

14.2.1  The  criteria  given  in  14.2.1.1  to  14.2.1.5  shall 
be  met  while  selecting  habitat  site  for  construction 
workers. 

14.2.1.1  Workers  habitat  shall  be  located  away  from 
overhead  electrical  lines.  If  due  to  non-availability  of 
space,  the  habitat  need  to  be  located  in  the  proximity 
of  electrical  line,  minimum  clearances  as  given  in  Part  3 
‘Development  Control  Rules  and  General  Building 
Requirements’  of  the  Code  shall  be  provided. 

14.2.1.2  Workers’  habitat  shall  be  located  sufficiently 
away  from  areas  like  sewage  channels,  effluent 
treatment  plants,  garbage  dumping  yards,  etc. 

14.2.1.3  The  site  selected  shall  be  such  that  it  does  not 
get  flooded  during  monsoon  and  drainage  system 
available  around  the  site  for  run-off  water. 

14.2.1.4  The  site  shall  be  separated  from  the 
construction  site/public  area  by  physical  barrier  such 
as  fences. 

14.2.1.5  Appropriate  provisions  shall  be  made  for 
access  to  the  site;  and  depending  upon  the  location 
thereof,  transportation  of  workers  from  their  habitat  to 
work  locations. 


14.3  Minimum  Area  Requirements 

The  area  requirements  as  given  in  Table  1  shall  be 
adopted  in  a  construction  workers’  habitat. 

For  female  workers  and  if  workers’  accommodation  is 
provided  for  families  of  workers,  separate  sanitation 
facility  for  women  with  adequate  privacy  shall  be 
provided  as  per  Table  1 . 


Table  1  Area  Requirements  in  Construction 
Workers’  Habitat 

(Clause  14.3) 


SI 

No. 

(1) 

Description 

(2) 

Quantity 

(3) 

i) 

Minimum  floor  area  per 
person 

3.6  m2 

ii) 

Maximum  number  of 
persons  per  room 

10 

iii) 

Minimum  height  of  the 

2.7  m,  if  two  tier  beds 

room 

are  provided  3  m 

iv) 

Minimum  area  of  kitchen 
per  person 

0.60  nr 

v) 

Number  of  lavatories,  Min 

1  per  10  person 

vi) 

Number  of  bathrooms,  Min 

1  unit  per  1 5  person 

vii) 

Number  of  urinals,  Min 

1  per  25  person 

14.4  Minimum  Facilities  to  be  Provided  in  Rooms 

Following  minimum  facilities  shall  be  provided  in 

rooms  of  construction  workers: 

a)  Adequate  natural  light  during  the  day  time  and 
adequate  artificial  light; 

b)  Adequate  ventilation  to  ensure  sufficient 
movement  of  air  in  all  conditions  of  weather 
and  climate; 

c)  Lockable  doors  and  windows,  provided  with 
mosquito  screens  where  conditions  warrant; 

d)  A  separate  bed  for  each  worker; 

e)  Adequate  furniture  for  each  worker  to  secure 
his  or  her  personal  belongings,  such  as,  a 
ventilated  clothes  locker  which  can  be  locked 
by  the  occupant  to  ensure  privacy; 

f)  Separate  storage  for  work  boots  and  other 
personal  protection  equipment  to  be  provided 
depending  on  conditions; 

g)  As  far  as  practicable,  sleeping  rooms  be  so 
arranged  that  shifts  are  separated  and  that  no 
workers  working  during  the  day  share  a  room 
with  workers  on  night  shifts; 

h)  Beds  not  to  be  arranged  in  tiers  of  more  than 
two. 

14.5  Design  and  Construction  of  the  Habitat 

Design  and  construction  of  the  workers’  habitat  meeting 


60 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


the  requirements  given  in  14.2  to  14.4  shall  be 
structurally  sound  and  may  be  constructed  at  site  or 
erected  as  prefabricated  single/two  storied 
accommodation. 

14.6  Sanitary  Facilities 

Following  sanitary  facilities  shall  be  provided  at  habitat 
for  construction  workers  at  site: 

a)  Every  lavatory  shall  be  under  cover  and  so 
partitioned  off  as  to  secure  privacy,  and  shall 
have  a  proper  door  and  fastenings. 

b)  Where  both  male  and  female  building  workers 
are  employed,  separate  sanitary  facilities  shall 
be  provided  for  female  workers.  There  shall 
be  displayed  outside  each  block  of  lavatories 
or  urinals  a  notice  containing  therein  ‘For  Men 
Only’  or  ‘For  Women  Only’,  as  the  case  may 
be,  written  in  the  language  understood  by  the 
majority  of  such  workers.  Such  notice  shall 
also  bear  the  figure  of  a  man  or  of  a  woman, 
as  the  case  may  be. 

c)  Every  lavatory  or  urinal  shall  be  conveniently 
situated  and  accessible  to  building  workers  at 
all  times. 

d)  Every  lavatory  or  urinal  and  washing  facilities 
shall  be  adequately  lighted  and  shall  be 
maintained  in  a  clean  and  sanitary  condition 
at  all  times. 

e)  Every  lavatory  or  urinal  other  than  those 
connected  with  a  flush  sewage  system  shall 
comply  with  the  requirements  of  the  public 
health  authorities. 

f)  Water  seal  lavatories  may  be  provided  on  the 
basis  of  community  toilets  or  shared  toilets  as 
per  the  recommendation  given  in  good 
practice  [7(56)]. 

g)  Water  shall  be  provided  by  means  of  a  tap  or 
otherwise  so  as  to  be  conveniently  accessible 
in  or  near  every  lavatory  or  urinal. 

h)  The  walls,  ceilings  and  partitions  of  every 
lavatory  or  urinal  shall  be  white-washed  or 
colour-washed  once  in  every  period  of  six 
months. 

j)  Waste  water  from  wash  areas,  bathrooms  and 
toilets  shall  be  drained  in  septic  tanks/soak 
pits  and  suitably  disposed  in  municipal 
sewerage  systems.  For  very  large  habitat, 
sewage  treatment  plant  may  be  installed.  No 
waste  water  shall  be  discharged  to  ground  or 
other  sources  without  proper  treatment. 

k)  Septic  tanks/soak  pits  shall  be  located  at  a 
minimum  distance  of  18  m  from  the  wells. 
Location  of  septic  tank  shall  meet  the 
requirements  of  good  practice  [7(57)]. 


14.7  Drinking  Water  Requirements 

14.7.1  Sufficient  quantity  of  potable  water  shall  be 
made  available  for  drinking.  Drinking  water  shall  meet 
the  requirements  of  the  accepted  standard  [7(58)]  and 
water  quality  shall  be  monitored  regularly. 

14.7.2  Drinking  water  outlet  shall  be  so  located  such 
that  the  distance  to  travel  to  nearest  outlet  shall  not  be 
more  than  30  m.  Drinking  water  tanks  should  be  legibly 
marked  ‘Drinking  Water’  in  a  language  understood  by 
a  majority  of  the  workers  and  shall  be  located  at 
least  6  m  away  from  washing  place,  urinal  or  lavatory. 

14.7.3  Sampling  and  testing  of  drinking  water  for 
checking  its  conformity  to  meet  the  requirements 
of  14.7.1  should  be  carried  out  quarterly  through 
accredited  laboratory. 

14.7.4  Storage  tanks  shall  be  cleaned  as  part  of  regular 
maintenance  procedure  to  prevent  growth  of  slime  and 
collection  of  sediments. 

14.8  First  Aid  and  Medical  Facilities 

14.8.1  First  aid  centre  shall  be  established  in  the  habitat 
with  the  required  medical  facilities.  Trained  first  aiders/ 
male  nurse/doctor  shall  be  employed  in  the  First  Aid 
Centre  depending  on  the  number  of  workers 
accommodated.  Sufficient  number  of  first-aid  boxes 
shall  be  provided  and  maintained  and  the  box  shall  be 
distinctly  marked  ‘First-aid’  and  shall  be  equipped  with 
specified  articles. 

14.8.2  An  emergency  vehicle  shall  be  provided  or  an 
arrangement  shall  be  made  with  an  identified  nearby 
hospital  for  providing  ambulance  for  transportation  of 
serious  cases  of  accident  or  sickness  of  workers  to  the 
hospital  promptly.  Such  vehicle  should  be  maintained 
in  good  repair  and  should  be  equipped  with  standard 
facilities.  The  contact  details,  including  phone  numbers 
of  such  nearby  hospitals  shall  be  readily  available  to 
different  managers/supervisors/first-aid  facility  in¬ 
charge.  These  phone  numbers  shall  also  be  suitably 
displayed  at  site. 

14.8.3  Details  of  all  the  first-aid/medical  treatments 
shall  be  logged  in  the  first  aid  register. 

14.8.4  Lighting  of  300  lux  shall  be  maintained  in  the 
first  aid  centre. 

14.8.5  Health  check-up  of  all  the  workers  shall  be  done 
at  least  once  in  six  months  by  a  registered  medical 
practitioner. 

14.8.6  The  medical  facilities  shall  meet  the  provisions 
of  Building  and  other  Construction  Workers 
(Regulation  of  Employment  and  Conditions  of  Service) 
Act,  1996  and  rules  framed  thereunder. 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


61 


14.9  Cooking  Area 

Cooking  shall  not  be  permitted  in  the  living  area. 
Separate  designated  kitchen  shall  be  provided  meeting 
the  minimum  area  requirements  given  in  14.3.  Canteen 
and  cooking  facilities  should  provide  sufficient  space 
for  preparing  food  and  eating,  as  well  as  conform  to 
hygiene  and  safety  requirements.  When  workers  can 
individually  cook  their  meals,  they  should  be  provided 
with  a  space  separate  from  the  sleeping  areas.  Facilities 
must  be  kept  in  a  clean  and  sanitary  condition. 

14.10  Creches 

In  every  place  wherein  more  than  fifty  female  building 
workers  are  ordinarily  employed,  there  shall  be 
provided  and  maintained,  a  suitable  room  or  rooms  for 
the  use  of  children  under  the  age  of  six  years  of  such 
female  workers.  Such  rooms  shall, 

a)  provide  adequate  accommodation; 

b)  be  adequately  lighted  and  ventilated; 

c)  be  maintained  in  a  clean  and  sanitary 
condition;  and 

d)  be  under  the  charge  of  women  trained  in  the 
care  of  children  and  infants. 

14.11  Habitat  Operation  and  Maintenance 

14.11.1  A  detailed  plan  shall  be  prepared  for  the 
operation  and  maintenance  of  the  habitat  facilities.  The 
plan  shall  cover  all  aspects  of  the  operation,  preventive 
and  routine  maintenance. 

14.11.2  Qualified  and  experienced  in-house  electrical/ 
maintenance  personnel  shall  be  present  and  available. 
A  supervisor  shall  be  appointed  to  supervise  hygiene 
in  the  habitat  facilities.  Sufficient  cleaners  shall  be 
employed  to  ensure  that  the  buildings  and  sanitary 
facilities  are  always  clean  and  hygienic. 

14.11.3  Regular  pest  and  insect  control  measures  shall 
be  taken  up  to  avoid  mosquito/pest  breeding.  This  may 
be  done  through  an  approved  agency. 

14.11.4  Worker’s  transportation  may  be  done  with 
standard  passenger  vehicle/bus,  where  required. 

14.12  Fire  Prevention 

14.12.1  Fire  extinguishers  shall  be  provided  such  that 
one  should  not  have  to  travel  more  than  15m  distance 
to  access  a  fire  extinguisher. 

14.12.2  Diesel  generator  shed  and  inflammable  liquid 
storage  areas  shall  be  provided  with  foam  type  fire 
extinguishers  and  fire  buckets. 

14.12.3  Electrical  fittings  in  the  inflammable  storage 
areas  shall  be  flame  proof. 

14.12.4  ‘No  Smoking’  boards  shall  be  displayed  in  gas 
cylinder  and  flammable  liquid  storage  areas. 


14.12.5  All  the  security  and  habitat  maintenance 
personnel,  habitat  residents  and  site  workers  shall  be 
trained  on  use  of  fire  extinguishers. 

14.13  Recreation 

Internal  and  external  recreational  facilities  may  be  made 
available  depending  on  the  number  of  workers  to  be 
accommodated.  Reasonable  access  to  telephone  or 
other  modes  of  communications,  with  any  charges  for 
the  use  of  these  services  being  reasonable  in  amount, 
shall  be  provided. 

14.14  Security 

14.14.1  Adequate  number  of  security  personnel  shall 
be  deployed.  Specific  security  personnel  shall  be 
deployed  at  the  main  entry  gate  for  restricting 
unauthorized  entry  and  checking  vehicle/material  exit 
and  entry. 

14.14.2  Security  staff  shall  receive  adequate  training 
on  first  aid,  firefighting  and  emergency  preparedness. 
Security  staff  shall  have  a  good  understanding  about 
the  importance  of  respecting  workers’  rights  and  the 
rights  of  the  communities.  Security  staff  shall  have  the 
emergency  lights,  torches  and  other  accessories 
required  to  facilitate  during  emergency  situations. 

14.14.3  A  minimum  of  50  lux  lighting  shall  be 
maintained  in  the  roads,  parking  area,  boundary  wall 
and  other  general  areas  of  the  habitat. 

14.15  Other  Facilities 

Other  facilities  like  provisional  stores  with  separate 
counters  for  vegetables,  etc,  may  also  be  provided  in  a 
construction  workers  habitat. 

Facilities  like  induction/initiation  room  may  be  planned 
as  the  part  of  habitat  for  awareness,  education  and  other 
related  work  site  requirements. 

14.16  Habitat  Inspection 

Periodical  inspection  of  the  habitat  shall  be  carried  out 
by  an  identified  team  preferably  once  in  a  month.  The 
team  shall  record  their  findings  on  the  Inspection  Report 
form  and  team  shall  also  review  and  follow-up 
implementation  of  the  suggested  measures.  The  above 
periodic  inspection  report  of  the  habitat  should  be 
submitted  to  Project-in-Charge. 

14.17  Notwithstanding  the  requirements  given  in  14.1 
to  14.16,  all  provisions  given  in  relevant  Act/Rules/ 
Regulations  as  amended  from  time  to  time  shall  be 
followed;  in  this  regard,  reference  shall  also  be  made 
to  the  Building  and  other  Construction  Workers 
(Regulation  of  Employment  and  Conditions  of  Service) 
Act,  1996  and  the  rules/regulations  framed  thereunder. 


62 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


ANNEX A 

(■ Clause  8.2.1) 

CHECK  LIST  FOR  STACKING  AND  STORAGE  OF  MATERIALS 

SI  No.  Material/  Component  Base  Stack  Type  of  Cover 


Firm 

Hard 

Off- 

Heaps 

Tiers 

Flat 

Vertical 

Open 

Open  but 

Under 

Level 

Ground 

Floor 

Floor 

Covered 

Shed 

(1) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

(9) 

(10) 

(11) 

(12) 

1. 

Cement 

V 

V 

V 

2. 

Lime: 

a)  Quick  lime 

b)  Hydrated  lime 

V 

V 

V 

V 

V 

V 

3. 

Stones  and  aggregates: 
a)  Stones,  aggregates,  fly 

V 

V 

V 

ash  and  cinder 

b)  Veneering  stones 

V 

V 

V 

V 

4. 

Bricks  and  blocks 

V 

V 

V 

5. 

Tiles: 

a)  Clay  and  concrete 

V 

V 

V 

V 

floor,  wall  and  roof 
tiles 

b)  Ceramic  tiles 

V 

V 

V 

V 

6. 

Partially  pre-fabricated 
wall  and  roof  components: 

a)  RC  planks, 

V 

V 

V 

prefabricated  brick 
panels  and  ferro- 
cement  panels 

b)  Channel  units,  cored 

V 

V 

V 

units  and  L-Panels 

c)  Waffle  units,  RC 

V 

V 

V 

joists,  single  tee  and 
double  tee 

7. 

Timber 

V 

V 

V 

8. 

Steel 

V 

V 

V 

9. 

Aluminium  sections 

V 

V 

V 

10. 

Doors,  windows  and 
ventilators 

V 

V 

V 

11. 

Roofing  sheets: 
a)  AC 

V 

V 

V 

V 

b)  GI  and  aluminium 

V 

V 

V 

V 

sheets 

c)  Plastic  sheets 

V 

V 

V 

V 

12. 

Boards  like  plywood, 
particle  boards,  fibre 
boards,  blockboards  and 
gypsum  board 

V 

V 

V 

V 

PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


63 


ANNEX  A  —  ( Concluded ) 


(1) 

(2) 

(3) 

(4) 

(5) 

(6)  (7) 

(8) 

(9) 

(10) 

(ID 

(12) 

13. 

Plastic  and  rubber  flooring: 
a)  Sheets  in  rolls 

✓ 

✓ 

V 

b)  Tiles 

✓ 

✓ 

✓ 

V 

14. 

Glass  sheets 

✓ 

V 

15. 

Glass  bricks/blocks 

✓ 

V 

16. 

Cl,  GI  and  AC  pipes  and 

fittings: 

a)  Pipes 

✓ 

✓ 

✓ 

✓ 

b)  Cl  and  GI  fittings 

✓ 

y 

c)  AC  fittings 

✓ 

17. 

Polyethylene  pipes 

✓ 

s 

18. 

Unplasticized  PVC  pipes 

✓ 

✓ 

✓ 

✓ 

19. 

Bitumen,  road  tar,  asphalt, 
etc,  in  drums 

✓ 

✓ 

✓ 

20. 

Oil  paints 

21. 

Sanitary  appliances 

✓ 

✓ 

✓ 

LIST  OF  STANDARDS 


The  following  list  records  those  standards  which  are  IS  No. 


acceptable  as  ‘good  practice’  and  ‘accepted  standards’ 
in  the  fulfillment  of  the  requirements  of  the  Code.  The 
latest  version  of  a  standard  shall  be  adopted  at  the  time 
of  enforcement  of  the  Code.  The  standards  listed  may 

(Part  1)  :  1998 

be  used  by  the  Authority  for  conformance  with  the 

(Part  2)  :  2006 

requirements  of  the  referred  clauses  in  the  Code. 

(4) 

15883  (Part  6)  : 

In  the  following  list,  the  number  appearing  in  the  first 
column  within  parantheses  indicates  the  number  of  the 

2015 

reference  in  this  Part. 

(5) 

15883  (Part  7) 

IS  No. 

Title 

(1)  7337:2010 

Glossary  of  terms  in  project 
management  ( second 

(6) 

15883  (Part  2)  : 

revision) 

2013 

10400  :  2013 

Glossary  of  terms  in 
inventory  management 

(7) 

15883  (Part  3)  : 

(second  revision) 

2015 

15198  :  2014 

Glossary  of  terms  in  human 
resource  development 

(8) 

15883  (Part  4)  : 

(2)  16416  :  2016 

Construction  project 

management:  Project 

2015 

formulation  and 

(9) 

15883  (Part  8)  : 

appraisal  —  Guidelines 

2015 

(3)  14580 


Use  of  network  analysis  for 

proj ect  management  (10)  15883  (Part  9) 


Title 

Management,  planning, 
review,  reporting  and 
termination  procedures 

Use  of  graphic  techniques 
Guidelines  for  construction 
project  management:  Part  6 
Scope  management 
Guidelines  for  construction 
project  management:  Part  7 
Procurement  management 
(under  preparation) 
Guidelines  for  construction 
project  management:  Part  2 
Time  management 
Guidelines  for  construction 
project  management:  Part  3 
Cost  management 
Guidelines  for  construction 
project  management:  Part  4 
Quality  management 
Guidelines  for  construction 
project  management:  Part  8 
Risk  management 
Guidelines  for  construction 


64 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


IS  No. 


(11)  15883  (Part  10) 


(12)  15883  (Part  5)  : 
2013 


(13)  15883  (Part  11) 


(14)  15883  (Part  12)  : 
2016 

(15)  a )  Foundations 
1080  :  1985 


1904  :  1986 


2911 


(Part  1/Sec  1) : 
2010 


(Part  1/Sec  2) : 
2010 


(Part  1/Sec  3) : 
2010 


(Part  1/Sec  4)  : 
2010 

(Part  2)  :  1980 
(Part  3)  :  1980 

(Part  4)  :  2013 

2974 


Title 

project  management:  Part  8 
Communication  manage¬ 
ment  ( under  preparation ) 
Guidelines  for  construction 
project  management:  Part  10 
Human  resource  manage¬ 
ment  (under  preparation) 
Guidelines  for  construction 
project  management:  Part  5 
Health  and  safety  manage¬ 
ment 

Guidelines  for  construction 
project  management:  Part  11 
Sustainability  management 
(under  preparation) 
Guidelines  for  construction 
project  management:  Part  12 
Integration  management 

Code  of  practice  for  design 
and  construction  of  shallow 
foundations  on  soils  (other 
than  raft,  ring  and  shell) 
(second  revision) 

Code  of  practice  for  design 
and  construction  of 
foundations  in  soils: 
General  requirements  (third 
revision) 

Code  of  practice  for  design 
and  construction  of  pile 
foundations 

Concrete  piles,  Section  1 
Driven  cast  in-situ  concrete 
piles  (second  revision) 

Concrete  piles,  Section  2 
Board  cast  in-situ  concrete 
piles  (second  revision) 
Concrete  piles,  Section  3 
Precast  driven  concrete 
piles  (second  revision) 

Concrete  piles,  Section  4 
Precast  concrete  piles  in 
prebored  holes  (first 
revision) 

Timber  piles  (first  revision) 
Under-reamed  piles  (first 
revision) 

Load  test  on  piles  (second 
revision) 

Code  of  practice  for  design 


IS  No. 

(Part  1)  :  1982 

(Part  2)  :  1980 

(Part  3)  :  1992 

(Part  4)  :  1979 

(Part  5)  :  1987 

9456  :  1980 

9556  :  1980 

12070  :  1987 

13094  :  1992 

14593  :  1998 

15284 

(Part  1)  :  2003 
(Part  2)  :  2004 

b)  Masonry 
IS  No. 

1597 

(Part  1)  :  1992 


Title 

and  construction  of 
machine  foundations 
Foundations  for  reci¬ 
procating  type  machines 
(second  revision) 
Foundations  for  impact 
type  machines  (hammer 
foundations)  (first  revision) 
Foundations  for  rotary  type 
machines  (medium  and 
high  frequency)  (second 
revision) 

Foundations  for  rotary  type 
machines  of  low  frequency 
(first  revision) 
Foundations  for  impact 
machines  other  than 
hammers  forging  and 
stamping  press  pig  breakers 
(drop  crusher  and  jolter) 
(first  revision) 

Code  of  practice  for  design 
and  construction  of  conical 
and  hyperbolic  paraboidal 
types  of  shell  foundations 
Code  of  practice  for  design 
and  construction  of 
diaphragm  walls 

Code  of  practice  for  design 
and  construction  of  shallow 
foundations  on  rock 

Guidelines  for  selection  of 
ground  improvement 
techniques  for  foundation 
in  weak  soils 

Design  and  construction  of 
bored  cast-in-situ  piles 
founded  on  rocks  — 
Guidelines 

Design  and  construction  for 
ground  improvement: 

Stone  columns 

Preconsolidation  using 
vertical  drains 

Title 

Code  of  practice  for 
construction  of  stone 
masonry 

Rubble  stone  masonry  (first 
revision) 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


65 


IS  No. 

(Part  2)  :  1992 
2110  :  1980 

2212  :  1991 
2250  :  1981 

2572  :  2005 

3630  :  1992 

4407  :  1967 

4441  :  1980 

4442  :  1980 

4443  :  1980 

6041  :  1985 

6042  :  1969 

c)  Timber  and  Bamboo 
IS  No. 

1634  :  1992 

2366  :  1983 


Title 

Ashlar  masonry  (first 
revision) 

Code  of  practice  for  in-situ 
construction  of  walls  in 
buildings  with  soil-cement 
(first  revision) 

Code  of  practice  for 
brickwork  (first  revision) 
Code  of  practice  for 
preparation  and  use  of 
masonry  mortars  (first 
revision) 

Code  of  practice  for 
construction  of  hollow  and 
solid  concrete  block 
masonry  (first  revision) 

Code  of  practice  for 
construction  of  non-load 
bearing  gypsum  block 
partitions  (first  revision) 

Code  of  practice  for  reed 
walling 

Code  of  practice  for  use  of 
silicate  type  chemical 
resistant  mortars  (first 
revision) 

Code  of  practice  for  use  of 
sulphur  type  chemical 
resistant  mortars  (first 
revision) 

Code  of  practice  for  use  of 
resin  type  chemical 
resistant  mortars  (first 
revision) 

Code  of  practice  for 
construction  of  autoclaved 
cellular  concrete  block 
masonry  (first  revision) 

Code  of  practice  for 
construction  of  light  weight 
concrete  block  masonry 
(first  revision) 

Title 

Code  of  practice  for  design 
and  constructions  of  wood 
stair  for  houses  (second 
revision) 

Code  of  practice  for  nail- 
jointed  timber  construction 
(first  revision) 


IS  No. 

3670  :  1989 

4913  :  1968 

4983  :  1968 

5390  :  1984 

11096  :  1984 

12506  :  1988 

d)  Concrete 

IS  No. 

456  :  2000 

457  :  1957 

1343  :  2012 

2502  :  1963 

2541  :  1991 

3370 

(Part  1)  :  2009 
(Part  2)  :  2009 
(Part  3)  :  1 967 
3558  :  1983 


Title 

Code  of  practice  for 
construction  of  timber 
floors  (first  revision) 

Code  of  practice  for 
selection,  installation  and 
maintenance  of  timber 
doors  and  windows 

Code  of  practice  for  design 
and  construction  of  nail 
laminated  timber  beams 

Code  of  practice  for 
construction  of  timber 
ceilings  ( first  revision) 
Code  of  practice  for  design 
and  construction  of  bolt- 
jointed  timber  construction 

Code  of  practice  for 
improved  thatching  of  roof 
with  wrought  and  fire 
retardant  treatment 

Title 

Code  of  practice  for  plain 
and  reinforced  concrete 
(fourth  revision) 

Code  of  practice  for  general 
construction  of  plain  and 
reinforced  concrete  for 
dams  and  other  massive 
structures 

Code  of  practice  for  pre¬ 
stressed  concrete  (second 
revision) 

Code  of  practice  for 
bending  and  fixing  of  bars 
for  concrete  reinforcement 

Code  of  practice  for 
preparation  and  use  of  lime 
concrete  (second  revision) 
Code  of  practice  for 
concrete  structures  for  the 
storage  of  liquids: 

General  requirements  (first 
revision) 

Reinforced  concrete 
structures  (first  revision) 
Prestressed  concrete 
structures 

Code  of  practice  for  use  of 
immersion  vibrators  for 
consolidating  concrete 
(first  revision) 


66 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Title 


IS  No. 

4926  :  2003 

5817  :  1992 

7246  :  1974 

7861 

(Part  1)  :  1975 
(Part  2)  :  1981 
10262  :  2009 

10359  :  1982 

14687  :  1999 
e)  Steel 

IS  No. 

800  :  2007 

801  :  1975 

805  :  1968 

806  :  1968 

4000  :  1992 

4180  :  1967 

6533 


Title 

Code  of  practice  for  ready- 
mixed  concrete  ( second 
revision) 

Code  of  practice  for 
preparation  and  use  of  lime 
pozzolana  mixture  concrete 
in  buildings  and  roads  (first 
revision) 

Recommendations  for  use 
of  table  vibrators  for 
consolidating  concrete 

Code  of  practice  for  extreme 
whether  concreting: 
Recommended  practice  for 
hot  weather  concreting 
Recommended  practice  for 
cold  weather  concreting 

Guidelines  for  concrete  mix 
design  proportioning  (first 
revision) 

Code  of  practice  for 
manufacture  and  use  of 
lime  pozzolana  concrete 
blocks  for  paving 
Guidelines  for  falsework 
for  concrete  structures 

Title 

Code  of  practice  for  general 
construction  in  steel  (third 
revision) 

Code  of  practice  for  use  of 
cold  formed  light  gauge 
steel  structural  members  in 
general  building  construc¬ 
tion  (first  revision) 

Code  of  practice  for  use  of 
steel  in  gravity  water  tanks 
Code  of  practice  for  use  of 
steel  tubes  in  general 
building  construction  (first 
revision) 

Code  of  practice  for  high 
strength  bolts  in  steel 
structures  (first  revision) 

Code  of  practice  for 
corrosion  protection  of 
light  gauge  steel  sections 
used  in  building 
Code  of  practice  for  design 
and  construction  of  steel 


IS  No. 

(Part  1)  :  1989 

(Part  2)  :  1989 

8629  (Parts  1  to  3)  : 
1977 

9077  :  1979 

9172  :  1979 

f)  Flooring  and  Roofing 
658  :  1982 

1196  :  1978 

1197  :  1970 

1198  :  1982 

1443  :  1972 

2118  :  1980 

2119  :  1980 

2204  :  1962 

2571  :  1970 


chimneys: 

Mechanical  aspects  (first 
revision) 

Structural  aspects  (first 
revision) 

Code  of  practice  for 
protection  of  iron  and 
steel  structures  from 
atmospheric  corrosion 

Code  of  practice  of 
corrosion  protection  of 
steel  reinforcement  in  RB 
and  RCC  construction 
Recommended  design 
practice  for  corrosion 
prevention  of  steel 
structures 

Code  of  practice  for 
magnesium  oxychloride 
composition  floors  (second 
revision) 

Code  of  practice  for  laying 
bitumen  mastic  flooring 
(second  revision) 

Code  of  practice  for  laying 
of  rubber  floors  (first 
revision) 

Code  of  practice  for  laying, 
fixing  and  maintenance  of 
linoleum  floor  (first 
revision) 

Code  of  practice  for  laying 
and  finishing  of  cement 
concrete  flooring  tiles  (first 
revision) 

Code  of  practice  for 
construction  of  jack-arch 
type  of  building  floor  or 
roof  (first  revision) 

Code  of  practice  for 
construction  of  brick-cum- 
concrete  composite 
(Madras  terrace)  floor  or 
roof  (first  revision) 

Code  of  practice  for 
construction  of  reinforced 
concrete  shell  roof 

Code  of  practice  for  laying 
in-situ  cement  concrete 
flooring  (first  revision) 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


67 


Title 


IS  No. 

2700  :  1987 

2792  :  1964 

2858  :  1984 

3007 

(Part  1) :  1999 
(Part  2)  :  1999 
3670  :  1989 

5119 

(Part  1)  :  1968 
5318  :  1969 

5389  :  1969 

5390  :  1984 

5766  :  1970 
6061 

(Part  1)  :  1971 
(Part  2)  :  1981 
(Part  3)  :  1981 

(Part  4)  :  1981 
6332  :  1984 


Title 

Code  of  practice  for  roofing 
with  wooden  shingles  (first 
revision) 

Code  of  practice  for  design 
and  construction  of  stone 
slab  over  joist  floor 
Code  of  practice  for  roofing 
with  Mangalore  tiles  ( first 
revision) 

Code  of  practice  for  laying 
of  asbestos  cement  sheets 

Corrugated  sheets  (first 
revision) 

Semi-corrugated  sheets 
(first  revision) 

Code  of  practice  for 
construction  of  timber 
floors  (first  revision) 

Code  of  practice  for  laying 
and  fixing  of  sloped  roof 
coverings 
Slating 

Code  of  practice  for  laying 
of  flexible  PVC  sheet  and 
tile  flooring 

Code  of  practice  for  laying 
of  hard  wood  parquet  and 
wood  block  floors 

Code  of  practice  for 
construction  of  timber 
ceilings  (first  revision) 

Code  of  practice  for  laying 
burnt  clay  brick  flooring 

Code  of  practice  for 
construction  of  floor  and 
roof  with  joists  and  filler 
blocks 

With  hollow  concrete  filler 
blocks 

With  hollow  clay  filler 
blocks  (first  revision) 

Precast  hollow  clay  blocks 
joists  and  hollow  clay  filler 
blocks 

With  precast  hollow  clay 
block  slab  panels 

Code  of  practice  for 
construction  of  floors  and 
roofs  using  precast  doubly- 
curved  shell  units  (first 


IS  No. 


9472  :  1980 
10297  :  1982 


10440  :  1983 


10505  :  1983 


g)  Finishes 

IS  No. 
1346  :  1991 


1414  :  1989 
1477 

(Part  1)  :  1971 
(Part  2)  :  1971 
1609  :  1991 


1661  :  1972 

2114  :  1984 

2115  :  1980 

2338 

(Part  1) :  1967 
(Part  2)  :  1967 


revision) 

Code  of  practice  for  laying 
mosaic  parquet  flooring 
Code  of  practice  for  design 
and  construction  of  floors 
and  roofs  using  precast 
reinforced/pre  stressed 
concrete  ribbed  or  cored 
slab  units 

Code  of  practice  for 
construction  of  reinforced 
brick  and  RBC  floors  and 
roofs 

Code  of  practice  for 
construction  of  floors  and 
roofs  using  precast  concrete 
waffle  units 

Title 

Code  of  practice  for 
waterproofing  of  roofs  with 
bitumen  felts  (third 
revision) 

Code  of  practice  for  fixing 
wall  coverings 
Code  of  practice  for 
painting  of  ferrous  metals  in 
buildings 

Pretreatment  (first  revision) 
Painting  (first  revision) 
Code  of  practice  for  laying 
damp-proofing  treatment 
using  bitumen  felts  ( second 
revision) 

Code  of  practice  for 
application  of  cement  and 
cement  lime  plaster  finishes 
(first  revision) 

Code  of  practice  for  laying 
in-situ  terrazzo  floor  finish 
(first  revision) 

Code  of  practice  for  flat- 
roof  finish  :  Mud  Phuska 
(second  revision) 

Code  of  practice  for 
finishing  of  wood  and  wood 
based  materials 

Operations  and  work¬ 
manship 
Schedules 


68 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


IS  No. 

Title 

2394  :  1984 

Code  of  practice  for 
application  of  lime  plaster 
finish  (first  revision) 

2395 

Code  of  practice  for 
painting  concrete,  masonry 
and  plaster  surfaces 

(Part  1) :  1994 

Operations  and  work¬ 
manship  (first  revision) 

(Part  2) :  1994 

Schedule  (first  revision) 

2402  :  1963 

Code  of  practice  for 
external  rendered  finishes 

2441  :  1984 

Code  of  practice  for  fixing 
ceiling  covering  (first 
revision) 

2524 

Code  of  practice  for 
painting  of  non-ferrous 
metals  in  buildings 

(Part  1)  :  1968 

Pre-treatment 

(Part  2)  :  1968 

Painting 

3036  :  1992 

Code  of  practice  for  laying 
lime  concrete  for  a  water¬ 
proofed  roof  finish  (second 
revision) 

3067  :  1988 

Code  of  practice  for  general 
design  details  and 
preparatory  work  for  damp- 
proofing  and  waterproofing 
of  buildings  (first  revision) 

3140  :  1965 

Code  of  practice  for 
painting  asbestos  cement 
building  products 

4101 

Code  of  practice  for 
external  facing  and  veneers 

(Part  1)  :  1967 

Stone  facing 

(Part  2)  :  1967 

Cement  concrete  facing 

(Part  3)  :  1985 

Wall  tiling  and  mosaics 
(first  revision) 

4365  :  1967 

Code  of  practice  for 
application  of  bitumen 
mastic  for  waterproofing  of 
roofs 

4597  :  1968 

Code  of  practice  for 
finishing  of  wood  and  wood 
based  products  with 
nitrocellulose  and  cold 
catalysed  materials 

4631  :  1986 

Code  of  practice  for  laying 
of  epoxy  resin  floor 
toppings  (first  revision) 

5491  :  1969 

Code  of  practice  for  laying 

IS  No. 

Title 

in-situ  granolithic  concrete 
floor  topping 

6278  :  1971 

Code  of  practice  for  white¬ 
washing  and  colour 
washing 

6494  :  1988 

Code  of  practice  for 
waterproofing  of 

underground  water 

reservoirs  and  swimming 
pools  (first  revision) 

7198  :  1974 

Code  of  practice  for  damp¬ 
proofing  using  bitumen 
mastic 

7290  :  1979 

Recommendations  for  use 
of  polyethylene  film  for 
waterproofing  of  roofs  (first 
revision) 

9918  :  1981 

Code  of  practice  for  in-situ 
waterproofing  and  damp¬ 
proofing  treatments  with 
glass  fibre  tissue  reinforced 
bitumen 

10439  :  1983 

Code  of  practice  for  patent 
glazing 

16135  :  2014 

Code  of  practice  for  dry 
lining  and  partitioning 
using  gypsum  plasterboards 

16231 

Code  of  practice  of  use  of 
glass  in  buildings 

(Part  1)  :  2016 

General  methodology  and 
selection 

(Part  2)  :  2016 

Energy  and  light 

(Part  3)  :  2016 

Fire  and  loading 

(Part  4)  :  2014 

Safety  related  to  human 
impact 

Piping 

IS  No. 

Title 

783  :  1985 

Code  of  practice  for  laying 
of  concrete  pipes  (first 
revision) 

3114  :  1994 

Code  of  practice  for  laying 
of  cast  iron  pipes  (second 
revision) 

4127  :  1983 

Code  of  practice  for  laying 
of  glazed  stoneware  pipes 
(first  revision) 

5329  :  1983 

Code  of  practice  for 
sanitary  pipe  work  above 
ground  for  buildings  (first 
revision) 

PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


69 


IS  No. 

5822  :  1994 

6530  :  1972 

7634 

(Part  1) :  1975 
(Part  2)  :  2012 

(Part  3)  :  2003 
13916  :  1994 

j)  Measurements 
IS  No. 

1200 

(Part  1)  :  1992 
(Part  2) :  1974 

(Part  3)  :  1976 
(Part  4)1976 

(Part  5)  :  2013 
(Part  6)  :  1974 

(Part  7)  :  2013 
(Part  8)  :  1993 

(Part  9)  :  1973 

(Part  10)  :  2013 

(Part  11)  :  2013 

(Part  12)  :  1976 
(Part  13)  :  1994 


Title 

Code  of  practice  for  laying 
of  welded  steel  pipes  for 
water  supply  ( second 
revision) 

Code  of  practice  for  laying 
of  asbestos  cement  pressure 
pipes 

Code  of  practice  for 
plastics  pipe  work  for 
portable  water  supplies 
Choice  of  materials  and 
general  recommen-dations 
Laying  and  jointing 
polyethylene  (PE)  pipes 
(first  revision) 

Laying  and  jointing  of 
unplasticized  PVC  pipes 
Code  of  practice  for 
installation  of  glass  fibre 
reinforced  plastic  piping 
system 

Title 

Method  of  measurement  of 
building  and  civil 
engineering  works 
Earthwork  (fourth  revision) 
Concrete  work  (third 
revision) 

Brickwork  (third  revision) 
Stone  masonry  (third 
revision) 

Formwork  (fourth  revision) 
Refactory  work  (second 
revision) 

Hardware  (third  revision) 
Steel  work  and  iron  work 
( fourth  revision) 

Roof  covering  (including 
cladding)  (second  revision) 
Ceiling  and  linings  (third 
revision) 

Paving,  floor  finishes  dado 
and  skirting  (fourth 
revision) 

Plastering  and  pointing 
( third  revision) 

White  washing,  colour 
washing,  distempering  and 
painting  of  building 
surfaces  (fifth  revision) 


IS  No. 

(Part  14)  :  1984 
(Part  15)  :  1987 

(Part  16)  :  1979 

(Part  17)  :  1985 

(Part  18)  :  1974 

(Part  19)  :  1981 

(Part  20)  :  1981 

(Part  21)  :  1973 

(Part  23)  :  1988 
(Part  24)  :  1983 

(Part  27)  :  2013 

3861  :  2002 

k)  Others 

IS  No. 

1081  :  1960 

1649  :  1962 

1946  :  1961 

2470 

(Part  1)  :  1985 

(Part  2) :  1985 

2527  :  1984 


Title 

Glazing  (third  revision) 

Paining,  polishing, 
varnishing,  etc  (fourth 
revision) 

Laying  of  water  and  sewer 
lines  including  appurtenant 
items  (third  revision) 
Roadwork  including  air 
field  pavements  (third 
revision) 

Demolition  and  dis¬ 
mantling  (third  revision) 

Water  supply,  plumbing  and 
drains  (third  revision) 
Laying  of  gas  and  oil  pipe 
lines  (third  revision) 

Woodwork  and  joinery 
(second  revision) 

Piling  (fourth  revision) 
Well  foundations  (third 
revision) 

Earth  work  done  by 
mechanical  appliances 

Method  of  measurement  of 
plinth,  carpet  and  rentable 
areas  of  buildings  (second 
revision) 

Title 

Code  of  practice  for  fixing 
and  glazing  of  metal  (steel 
and  aluminium)  doors, 
windows  and  ventilators 

Code  of  practice  for  design 
and  construction  of  flues 
and  chimneys  for  domestic 
heating  appliances 

Code  of  practice  for  use  of 
fixing  devices  in  walls, 
ceilings  and  floors  of  solid 
construction 

Code  of  practice  for 
installation  of  septic  tanks 
Design  criteria  and 
construction  (second 
revision) 

Secondary  treatment  and 
disposal  of  septic  tank 
effluent  (second  revision) 
Code  of  practice  for  fixing 
rain-water  gutters  and  down 


70 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Title 


IS  No. 

Title 

pipes  for  roof  drainage 
(first  revision) 

3414  :  1968 

Code  of  practice  for  design 
and  installation  of  joints  in 
buildings 

3548  :  1988 

Code  of  practice  for  glazing 
in  buildings  (first  revision) 

3558  :  1983 

Code  of  practice  for  use  of 
immersion  vibrators  for 
consolidating  concrete 
(first  revision) 

3935  :  1966 

Code  of  practice  for 
composite  construction 

4326  :  2013 

Code  of  practice  for 
earthquake  resistant  design 
and  construction  of 
buildings  (third  revision) 

4913  :  1968 

Code  of  practice  for 
selection,  installation  and 
maintenance  of  timber 
doors  and  windows 

6313 

Code  of  practice  for  anti¬ 
termite  measures  in 
buildings 

(Part  1)  :  1981 

Constructional  measures 
(first  revision) 

(Part  2)  :  2013 

Pre-constructional 
chemical  treatment 

measures  (third  revision) 

(Part  3)  :  2013 

Treatment  for  existing 
buildings  (third  revision) 

6924  :  1973 

Code  of  practice  for  the 
construction  of  refuse 
chutes  in  multistoreyed 
buildings 

7246  :  1974 

Recommendation  for  use  of 
table  vibrators  for 
consolidating  concrete 

8147  :  1976 

Code  of  practice  for  use  of 
aluminium  alloys  in 
structures 

15345  :  2003 

Code  of  practice  for 
installation  of  frameless 
door  and  window  shutters 

15916  :  2010 

Code  of  practice  for  buil¬ 
ding  design  and  erection 
using  prefabricated 

concrete 

15917  :  2010 

Code  of  practice  for 
building  design  and 
erection  using  mixed/ 
composite  construction 

IS  No. 

(16)  2750  :  1964  Specification  for  steel 

scaffoldings 

14687  :  1999  Guidelines  for  falsework 

for  concrete  structures 

3696  (Part  1)  :  1987  Safety  code  for  scaffolds 
and  ladders:  Part  1 
Scaffolds 

Code  of  practice  for  steel 
tubular  scaffolding 
Definitions  and  materials 
Safety  regulations  for 
scaffolding  (first  revision) 

(17)  6521  (Part  1)  :  1972  Code  of  practice  for  design 
of  tower  cranes:  Part  1 
Static  and  rail  mounted 
Cranes  —  control  —  layout 
and  characteristics:  Part  3 
Tower  cranes 

Guidelines  for  falsework 
for  concrete  structures 
Safety  code  for  excavation 
work  (first  revision ) 

Recommendations  for 
preventive  measure  against 
hazards  at  workplaces  : 
Part  5  Fire  protection 

Guidelines  for  safe  use  of 
products  containing 
asbestos  :  Part  1  Asbestos 
cement  products 

Specification  for  portable 
fire  extinguishers  — 
Performance  and 

construction 

Specification  for  wheeled 
fire  extinguishers  — 
Performance  and 

construction 

Code  of  practice  for 
selection,  installation  and 
maintenance  of  first-aid  fire 
extinguishers  (fourth 
revision) 

Code  of  practice  for  fire 
precautionary  measures  in 
construction  of  temporary 
structures  and  pandals 
(second  revision) 

Code  of  practice  patent 
glazing 

Guidelines  for  falsework 
for  concrete  structures 


4014 

(Part  1)  :  1967 
(Part  2)  :  2013 


(18)  13558  (Part  3)  : 

1995 

(19)  14687  :  1999 

(20)  3764  :  1992 

(21)  13416  (Part  5)  : 

1994 

(22)  11769  (Part  1)  : 

1987 

(23)  15683  :  2006 

16018  :  2012 

(24)  2190  :  2010 

(25)  8758  :  2013 

(26)  10439  :  1983 
14687  :  1999 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


71 


IS  No. 


(27)  4138  :  1977 

(28)  2925  :  1984 

(29)  2750  :  1964 

(30)  3696  (Part  1)  : 

4014  (Part  2)  : 

(31)  3696  (Part  2)  : 

(32)  4912  :  1978 

(33)  11461  :  1985 

(34)  5983  :  1980 

(35)  1179  :  1967 

(36)  2361  :  2002 

(37)  11057  :  1984 

(38)  3016  :  1982 

(39)  1084  :  2005 
2266  :  2002 

(40)  818  :  1968 

(41)  5916  :  2013 


Title 


IS  No. 


Title 


Safety  code  for  working  in 
compressed  air  (first 
revision) 

Specification  for  industrial 
safety  helmets  ( second 
revision) 

Specification  for  steel 
scaffoldings 

1987  Safety  code  for  scaffolds 
and  ladders:  Part  1 
Scaffolds 

2013  Code  of  practice  for  steel 
tubular  scaffolding:  Part  2 
Safety  provisions  for 
scaffolding  (first  revision) 
1991  Safety  code  for  scaffolds 
and  ladders:  Part  2  Ladders 
Safety  requirements  for 
floors  and  wall  openings, 
railing  and  toe  boards  (first 
revision) 

Code  of  practice  for 
compressor  safety 
Specification  for  eye- 
protectors  (first  revision) 
Specification  for  equipment 
for  eye  and  face  protection 
during  welding  (first 
revision) 

Specification  for  bull-dog 
grips  (third  revision) 
Specification  for  industrial 
safety  nets 

Code  of  practice  for  fire 
precautions  in  welding  and 
cutting  operations  (first 
revision) 

Specification  for  manila 
ropes  (fifth  revision) 
Specification  for  steel  wire 
ropes  for  general 
engineering  purposes  (forth 
revision) 

Code  of  practice  for  safety 
and  health  requirements  in 
electric  and  gas  welding 
and  cutting  operations  (first 
revision) 

Constructions  involving 
use  of  hot  bituminous 
materials  —  Code  of  safety 


(42)  13416  (Part  4)  : 
1994 

(43)  15683  :  2006 

(44)  819  :  1957 

1261  :  1959 
3016  :  1982 

4081  :  2013 

4138  :  1977 

9595  :  1996 

10178  :  1995 

(45)  3844  :  1989 


5290  :  1993 

(46)  13416  (Part  2)  : 
1992 


(47)  13416  (Part  1)  : 
1992 


(48)  13416  (Part  3)  : 
1994 


Recommendations  for 
preventive  measure  against 
hazards  at  workplaces  :  Part 
4  Timber  structure 
Portable  fire  extinguishers 
—  Performance  and 
construction  —  Speci¬ 
fication 

Code  of  practice  for 
resistance  spot  welding  for 
light  assemblies  in  mild 
steel 

Code  of  practice  for  seam 
welding  in  mild  steel 

Code  of  practice  for  fire 
precautions  in  welding  and 
cutting  operations  (first 
revision) 

Blasting  and  related  drilling 
operations  —  Code  of 
Safety  (second  revision) 

Safety  code  for  working  in 
compressed  gas  (first 
revision) 

Recommendations  for 
metal  arc  welding  of  carbon 
and  carbon  manganese 
steels  (first  revision) 

Recommended  procedure 
for  C02  gas  shielded  metal- 
arc  welding  of  structural 
steels  (first  revision) 

Code  of  practice  for 
installation  and 

maintenance  of  internal  fire 
hydrants  and  hose  reels  on 
premises  (first  revision) 
Specification  for  landing 
valves  (third  revision) 
Recommendation  for 
preventive  measures 
against  hazards  at  work 
places:  Part  2  Fall 
prevention 

Recommendation  for 
preventive  measures 
against  hazards  at  work 
places:  Part  1  Falling 
material  hazard  prevention 
Recommendation  for 
preventive  measures 
against  hazards  at  work 


72 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


IS  No. 

Title 

places:  Part  3  Disposal  of 
debris 

274 

Specification  for  shovels 

(Part  1)  :  1981 

General  purpose  shovels 
(, third  revision) 

(Part  2) :  1981 

Heat-treated  shovels  (third 
revision) 

663  :  1980 

Specification  for  adzes 
(second  revision) 

704  :  1984 

Specification  for  crow  bars 
and  claw  bars  (second 
revision) 

841  :  1983 

Specification  for  steel 
hammers  (second  revision) 

844 

Specification  for  screw 
drivers 

(Part  2)  :  1979 

Dimensions  (second 

revision) 

(Part  3)  :  1979 

Dimensions  for  screw 
drivers  for  recessed  head 
screws  (second  revision) 

1630  :  1984 

Specification  for  Mason’s 
tools  for  plaster  work  and 
pointing  work  (first 
revision) 

1759  :  1986 

Specification  for  Powrahs 
(second  revision) 

1791  :  1985 

Specification  for  batch  type 
concrete  mixers  (second 
revision) 

1930  :  2003 

Woodworking  tools  — 
Chisels  and  gouges  (third 
revision) 

1931  :  2000 

Specification  for  engineer’s 
files  (third  revision) 

2028  :  2004 

Specification  for  open  jaw 
wrenches  (spanners) 

(fourth  revision) 

2029  :  1998 

Specification  for  ring 
wrenches  (spanners) 

(fourth  revision) 

2030  :  1989 

Specification  for  box 
spanners  (second  revision) 

2094 

Specification  for  heater  for 
bitumen  (tar)  and  emulsion 
(second  revision) 

(Part  1) :  1996 

Specification  (second 
revision) 

(Part  2) :  1999 

Bitumen  sprayer  (third 
revision) 

IS  No. 

Title 

(Part  3)  :  1999 

Emulsion  (third  revision) 

2431  :  1963 

Specification  for  steel 
wheel  barrows  (single 
wheel-type) 

2438  :  1963 

Specification  for  roller  pan 
mixer 

2505  :  1992 

Specification  for  concrete 
vibrators,  immersion  type 
(General  requirements) 
(third  revision) 

2506  :  1985 

General  requirements  for 
screed  board  concrete 
vibrators  (first  revision) 

2514  :  1963 

Specification  for  concrete 
vibrating  tables 

2587  :  1975 

Specification  for  pipes 
vices  (open  side  type  and 
fixed  sides  type)  (first 
revision) 

2588  :  1975 

Specification  for  black¬ 
smith’s  vices  (first  revision) 

2722  :  1964 

Specification  for  portable 
swing  weigh  batchers  for 
concrete  (single  and  double 
bucket  type) 

2852  :  1998 

Specification  for  carpenters 
augers  (first  revision) 

3066  :  1965 

Specification  for  hot 
asphalt  mixing  plants 

3251  :  1965 

Specification  for  asphalt 
paver  finisher 

3365  :  1965 

Specification  for  floor 
polishing  machines 

3559  :  1966 

Specification  for  pneumatic 
concrete  breakers 

3587  :  1986 

Specification  for  rasps 
(second  revision) 

3650  :  1981 

Specification  for 

combination  side  cutting 
pliers  (second  revision) 

3938  :  1983 

Specification  for  electric 
wire  rope  hoists  (second 
revision) 

4003 

Specification  for  pipe 
wrenches 

(Part  1)  :  1978 

General  purposes  (first 
revision) 

(Part  2)  :  1986 

Heavy  duty  (first  revision) 

PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


73 


IS  No. 

Title 

4017  :  1992 

Specification  for  carpenters 
squares  (first  revision) 

4095  :  1991 

Specification  for  pincers 
(second  revision) 

4183  :  1967 

Specification  for  metal 
hand  rammers 

4184  :  1967 

Specification  for  steel 
wheel  barrows  (with  two 
wheels) 

4508  :  1992 

Specification  for  open 
ended  slugging  wrenches 
(spanners)  (first  revision) 

4915  :  1968 

Specification  for  welders 
chipping  hammer 

5066  :  1969 

Specification  for  glass 
pliers 

5067  :  1969 

Specification  for  fencing 
pliers 

5087  :  1969 

Specification  for  wire 
stripping  pliers 

5098  :  1969 

Specification  for  cross  cut 
and  rip  saws 

5123  :  1969 

Specification  for  tenon  and 
dovetail  saws 

5169  :  1986 

Specification  for  hack-saw 
frames  (first  revision) 

5200  :  1998 

Specification  for  bolt 
clippers  (first  revision) 

5658  :  1990 

Specification  for  snipenose 
pliers  (first  revision) 

5663  :  1970 

Specification  for  brick  and 
mason’s  chisels 

5684  :  1970 

Specification  for  pipe  vices 
(chain  type) 

5697  :  1970 

Specification  for  ripping 
chisels 

5889  :  1994 

Specification  for  vibratory 
plate  compactor  (first 
revision) 

5890  :  2004 

Mobile  hot  mix  asphalt 
plants,  light  duty  — 
Requirements  (first 

revision) 

5891  :  1970 

Specification  for  hand- 
operated  concrete  mixer 

5995  :  1971 

Specification  for  pipe  grip 
pliers 

6007  :  1971 

Specification  for  pipe  vices 
(hinged  type) 

IS  No. 

Title 

6078  :  1986 

Specification  for  Lineman’s 
pliers  (second  revision) 

6087  :  1971 

Specification  for  metal 
cutting  shears 

6118  :  1991 

Specification  for  multiple 
slip  joint  pliers  (first 
revision) 

6149  :  1984 

Specification  for  single 
ended  open  jaw  adjustable 
wrenches  ((first  revision) 

6375  :  1991 

Specification  for  wood 
splitting  wedges  (first 
revision) 

6389  :  1998 

Specification  for 

combination  wrenches  with 
equal  openings  (second 
revision) 

6428  :  1972 

Specification  for  pile  frame 

6430  :  1985 

Specification  for  mobile  air 
compressor  for  construct¬ 
ion  purposes  (first  revision) 

6433  :  1972 

Specification  for  guniting 
equipment 

6546  :  1989 

Specification  for  claw 
hammers  (first  revision) 

6836  :  1973 

Specification  for  hand 
snaps  and  set-ups  for  solid 
rivets 

6837  :  1973 

Specification  for  three 
wheel  type  pipe  cutter 

6841  :  1973 

Specification  for  wrecking 
bars 

6861  :  1973 

Specification  for  engineers’ 
scrapers 

6881  :  1973 

Specification  for  link  type 
pipe  cutters 

6891  :  1973 

Specification  for 

carpenter’s  auger  bits 

6892  :  1973 

Specification  for  black¬ 
smith’s  brick-iron 

7041  :  1973 

Specification  for 

carpenter’s  plain  brace 

7042  :  1973 

Specification  for 

carpenter’s  ratchet  brace 

7077  :  1973 

Specification  for  bending 
bars 

7958  :  1976 

Specification  for  hand  vices 

8202  :  1999 

Specification  for  car¬ 
penter’s  wooden  bodied 
planes  (first  revision) 

74 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


IS  No. 


Title 


IS  No. 


Title 


8671  :  1977 

(50)  7293  :  1974 

(51)  4130  :  1991 

(52)  13935  :  2009 

(53)  13828  :  1993 


Specification  for  nail  puller 

Safety  code  for  working 
with  construction 

machinery 

Safety  code  for  demolition 
of  buildings  {second 
revision) 

Guidelines  for  repair  and 
seismic  strengthening  of 
masonry  buildings  {first 
revision) 

Improving  earthquake 
resistance  of  low  strength 
masonry  buildings  — 
Guidelines 


(54)  13827  :  1993 

(55)  15988  :  2013 

(56)  13727  :  1993 

(57)  2470  (Part  1)  : 

1985 

(58)  10500  :  2012 


Improving  earthquake 
resistance  of  earthen 
buildings  —  Guidelines 
Seismic  evaluation  and 
strengthening  of  existing 
reinforced  concrete 

buildings  —  Guidelines 

Guidelines  for 

requirements  of  cluster 
planning  for  housing 

Code  of  practice  for 
installation  of  septic 
tanks:  Part  1  design,  criteria 
and  construction  {second 
revision) 

Specification  for  drinking 
water  {second  revision) 


PART  7  CONSTURCTION  MANAGEMENT,  PRACTICES  AND  SAFETY 


75 


NATIONAL  BUILDING  CODE  OF  INDIA 

PART  8  BUILDING  SERVICES 

Section  1  Lighting  and  Natural  Ventilation 


BUREAU  OF  INDIAN  STANDARDS 


CONTENTS 


FOREWORD  ...  3 

1  SCOPE  ...  5 

2  TERMINOLOGY  ...  5 

3  ORIENTATION  OF  BUILDING  ...  8 

4  LIGHTING  ...  11 

5  VENTILATION  ...  35 

ANNEX  A  METHOD  OF  CALCULATING  SOLAR  LOAD  ON  VERTICAL  ...  46 

SURFACES  OF  DIFFERENT  ORIENTATION 

ANNEX  B  SKY  COMPONENT  TABLES  ...  49 

LIST  OF  STANDARDS  ...  55 


2 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


National  Building  Code  Sectional  Committee,  CED  46 


FOREWORD 

This  Code  (Part  8/Section  1)  covers  requirements  and  methods  for  lighting  and  natural  ventilation  of  buildings. 

Illumination  levels  for  different  tasks  are  recommended  to  be  achieved  either  by  daylighting  or  artificial  lighting 
or  a  combination  of  both.  This  Section,  read  together  with  Part  8  ‘Building  Services,  Section  2  Electrical  and 
Allied  Installations’  of  the  Code,  adequately  covers  the  illumination  levels  required  and  methods  of  achieving  the 
same. 

Ventilation  requirements  to  maintain  air  quality  and  control  body  odours  in  terms  of  air  changes  per  hour  and  to 
ensure  thermal  comfort  and  heat  balance  of  body  are  laid  for  different  occupancies  and  the  methods  of  achieving 
the  same  by  natural  means  are  covered  in  this  Section.  The  provisions  on  mechanical  ventilation  are  covered  in 
Part  8  ‘Building  Services,  Section  3  Air  conditioning,  Pleating  and  Mechanical  Ventilation’  of  the  Code. 

Climatic  factors  which  normally  help  in  deciding  the  orientation  of  the  buildings  to  get  desirable  benefits  of 
lighting  and  natural  ventilation  inside  the  buildings  are  also  covered  in  this  Section. 

This  Section  was  first  published  in  1970.  The  first  revision  of  the  Section  was  brought  out  in  1983.  In  the  second 
revision,  some  provisions  were  updated  based  on  the  information  given  in  the  SP  41 : 1987  ‘Handbook  on  functional 
requirements  of  buildings  (other  than  industrial  buildings)’;  other  major  changes  in  the  last  revision  included 
rationalization  of  definitions  and  inclusion  of  definitions  for  some  more  terms;  inclusion  of  climatic  classification 
map  of  India  based  on  a  new  criteria;  updating  of  data  on  total  solar  radiations  incident  on  various  surfaces  of 
buildings  for  summer  and  winter  seasons;  inclusion  of  design  guidelines  for  natural  ventilation;  reference  to 
Part  8  ‘Building  Services,  Section  3  Air  Conditioning,  Heating  and  Mechanical  Ventilation’  of  the  Code  for 
guidelines  on  mechanical  ventilation,  was  made,  where  these  provisions  were  covered  exhaustively;  inclusion  of 
rationalized  method  for  estimation  of  desired  capacity  of  ceiling  fans  and  their  optimum  height  above  the  floor  for 
rooms  of  different  sizes;  incorporation  of  design  sky  illuminance  values  for  different  climatic  zones  of  India,  etc. 
Energy  efficiency  was  another  important  aspect  which  was  taken  care  of  in  the  last  revision  of  the  Code.  Accordingly, 
the  relevant  requirements  for  energy  efficient  system  for  lighting  and  natural  ventilation  were  duly  included  in  the 
concerned  provisions  under  the  Section. 

As  a  result  of  experience  gained  on  implementation  of  2005  version  of  the  Code  and  feedback  data  received,  a 
need  was  felt  to  revise  this  Section.  This  draft  revision  has,  therefore,  been  formulated  to  take  care  of  these.  The 
significant  changes  incorporated  in  this  revision  are: 

a)  Calculation  for  solar  load  has  been  elaborated,  and  a  detailed  ‘Method  of  Calculating  Solar  Load  on 
Vertical  Surfaces  in  Different  Orientation’  has  been  added  in  Annex  A,  supporting  the  relevant  provisions. 

b)  Detailed  provisions  on  sky  component  calculation  procedure  have  been  included  along  with  examples  in 
Annex  B  supporting  the  relevant  clauses. 

c)  Reference  to  SP  41  :  1987  for  obtaining  coefficient  utilization  for  detennination  of  luminous  flux  has 
been  included. 

d)  Provisions  relating  to  efficient  artificial  light  source  and  luminaires  have  been  updated. 

e)  Modem  lighting  techniques  such  as  LED  and  induction  light  have  been  included  vis-a-vis  their  energy 
consumption. 

f)  Provisions  relating  to  photocontrols  for  artificial  lights  have  been  updated. 

g)  Definitions  and  enabling  provision  for  lighting  shelves  and  light  pipes  have  been  included. 

h)  Provisions  related  to  thermal  comfort  clause  have  been  elaborated  including  therein  indices  such  as 
effective  temperature,  adaptive  thermal  comfort  along  with  elaborations  on  tropical  summer  index. 

j)  Design  guidelines  for  natural  ventilation  have  been  elaborated  with  illustrations. 

k)  Provisions  related  to  determination  of  rate  of  ventilation,  particularly  on  combined  effect  of  wind  and 
thermal  actions,  have  been  elaborated. 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


3 


m)  Provision  on  colour  rendering  has  been  included  in  line  with  that  in  SP  72  :  2010  ‘National  Lighting 
Code  2010’. 

n)  Various  other  existing  provisions  have  been  updated  based  on  the  latest  technical  developments  in  the 
field. 


The  provisions  of  this  Section  are  without  prejudice  to  the  various  acts,  rules  and  regulations  including  the  Factories 
Act,  1948  and  rules  and  regulations  framed  thereunder. 


The  information  contained  in  this  Section  is  largely  based  on  the  following  Indian  Standards/Special  Publications: 


IS  2440  :  1975 
IS  3103  :  1975 
IS  3362  :  1977 
IS  3646  (Part  1) 

IS  7662  (Part  1) 
IS  11907  :  1986 
SP  32  :  1986 
SP  41  :  1987 


Guide  for  daylighting  of  buildings  ( second  revision) 

Code  of  practice  for  industrial  ventilation  (first  revision ) 

Code  of  practice  for  natural  ventilation  of  residential  buildings  (first  revision) 

1992  Code  of  practice  for  interior  illumination:  Part  1  General  requirements  and 
recommendations  for  working  interiors  (first  revision) 

1974  Recommendations  for  orientation  of  buildings  :  Part  1  Non-industrial  buildings 
Recommendations  for  calculation  of  solar  radiation  on  buildings 
Handbook  on  functional  requirements  of  industrial  buildings  (lighting  and  ventilation) 
Handbook  on  functional  requirements  of  buildings  other  than  industrial  buildings 


Provisions  given  in  National  Lighting  Code,  ‘SP  72  :  2010’  may  also  be  referred. 


The  following  publication  has  also  been  referred  to  in  the  formulation  of  this  Section: 

Report  on  energy  conservation  in  buildings,  submitted  to  Department  of  Power,  Ministry  of  Energy  by  CSIR- 
Central  Building  Research  Institute,  Roorkee. 


All  standards,  whether  given  herein  above  or  cross-referred  to  in  the  main  text  of  this  Section,  are  subject  to 
revision.  The  parties  to  agreement  based  on  this  Section  are  encouraged  to  investigate  the  possibility  of  applying 
the  most  recent  editions  of  the  standards. 


For  the  purpose  of  deciding  whether  a  particular  requirement  of  this  Section  is  complied  with,  the  final  value, 
observed  or  calculated,  expressing  the  result  of  a  test  or  analysis,  shall  be  rounded  off  in  accordance  with  IS  2  :  1960 
‘Rules  for  rounding  off  numerical  values  (revised)’’ .  The  number  of  significant  places  retained  in  the  rounded  off 
value  should  be  the  same  as  that  of  the  specified  value  in  this  Section. 


4 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


NATIONAL  BUILDING  CODE  OF  INDIA 


PART  8  BUILDING  SERVICES 

Section  1  Lighting  and  Natural  Ventilation 


1  SCOPE 

1.1  This  Code  (Part  8/Section  1)  covers  requirements 
and  methods  for  lighting  and  natural  ventilation  of 
buildings. 

1.2  The  provisions  in  respect  of  lighting  and  ventilation 
in  sustainable  buildings  are  covered  in  Part  11 
‘Approach  to  Sustainability’  of  the  Code  which  shall 
be  used  in  conjunction  with  this  Section. 

1.3  For  all  buildings  and  facilities  open  to  and  used  by 
the  public,  including  all  forms  of  public  housing  by  the 
government/civic  bodies  and  private  developers, 
adequate  lighting  and  ventilation  for  barrier  free  access 
and  movement  within  and  around  buildings  by  elderly 
and  persons  with  disabilities  shall  be  ensured  in 
accordance  with  13  of  Part  3  ‘Development  Control 
Rules  and  General  Building  Requirements’  of  the  Code. 

2  TERMINOLOGY 

For  the  purpose  of  this  Section,  the  definitions  given 
below  shall  apply. 

2.1  Lighting 

2.1.1  Altitude  (9)  —  The  angular  distance  of  any  point 
of  celestial  sphere,  measured  from  the  horizon,  on  the 
great  circle  passing  through  the  body  and  the  zenith 
(see  Fig.  1). 

2.1.2  Azimuth  (®)  —  The  angle  measured  between 
meridians  passing  through  the  north  point  and  the  point 
in  question  (point  C  in  Fig.  1). 

2.1.3  Brightness  Ratio  or  Contrast  —  The  variations 
or  contrast  in  brightness  of  the  details  of  a  visual  task, 
such  as  white  print  on  blackboard. 

2.1.4  Candela  (cd)  —  The  SI  unit  of  luminous  intensity. 

Candela  =  1  lumen  per  steradian 

2.1.5  Central  Field  —  The  area  of  circle  around  the 
point  of  fixation  and  its  diameter,  subtending  an  angle 
of  about  2°  at  the  eye.  Objects  within  this  area  are  most 
critically  seen  in  both  their  details  and  colour. 

2.1.6  Clear  Design  Sky  —  The  distribution  of 
luminance  of  such  a  sky  is  non-uniform;  the  horizon  is 
brighter  than  the  zenith,  and  when  Lz  is  the  brightness 
at  zenith,  the  brightness  at  an  altitude  (0)  in  the  region 
away  from  the  sun,  is  given  by  the  expression: 

Le  =  Lz  cosec  0  (for  15°  <  0  <  90°) 

Le  =  Lz  cosec  15°  (for  0°  <  0  <  15°)  =  3.863  7  Lz 

2.1.7  Colour  Rendering  Index  (CRI)  —  Measure  of 
the  degree  to  which  the  psychophysical  colour  of  an 


Z 


REFERENCES 

O  -  Observer's  station  S  -  Geographical  south 

C  -  Celestial  body  E  -  Geographical  east 

Z  -  Zenith  W  -  Geographical  west 

NA  -  Nadir  N  -  Geographical  north 

Fig.  1  Altitude  and  Azimuth  of  a 
Celestial  Body 

object  illuminated  by  the  test  illuminant  conforms  to 
that  of  the  same  object  illuminated  by  the  reference 
illuminant,  suitable  allowance  having  been  made  for 
the  state  of  chromatic  adaptation. 

2.1.8  Correlated  Colour  Temperature  (CCT)  (K)  — 
The  temperature  of  the  Planckian  radiator  whose 
perceived  colour  most  closely  resembles  that  of  a  given 
stimulus  at  the  same  brightness  and  under  specified 
viewing  conditions. 

2.1.9  Daylight  Area  —  The  superficial  area  on  the 
working  plane  illuminated  to  not  less  than  a  specified 
daylight  factor,  that  is,  the  area  within  the  relevant 
contour. 

2.1.10  Daylight  Factor  —  The  measure  of  total 
daylight  illuminance  at  a  point  on  a  given  plane 
expressed  as  the  ratio  (or  percentage)  which  the 
illuminance  at  the  point  on  the  given  plane  bears  to  the 
simultaneous  illuminance  on  a  horizontal  plane  due  to 
clear  design  sky  at  an  exterior  point  open  to  the  whole 
sky  vault,  direct  sunlight  being  excluded. 

2.1.11  Daylight  Penetration  —  The  maximum  distance 
to  which  a  given  daylight  factor  contour  penetrates  into 
a  room. 

2.1.12  Direct  Solar  Illuminance  —  The  illuminance 
from  the  sun  without  taking  into  account  the  light  from 
the  sky. 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


5 


2.1.13  External  Reflected  Component  (ERC)  —  The 
ratio  (or  percentage)  of  that  part  of  the  daylight 
illuminance  at  a  point  on  a  given  plane  which  is  received 
by  direct  reflection  from  external  surfaces  as  compared 
to  the  simultaneous  exterior  illuminance  on  a  horizontal 
plane  from  the  entire  hemisphere  of  an  unobstructed 
clear  design  sky. 

2.1.14  Glare  —  A  condition  of  vision  in  which  there 
is  discomfort  or  a  reduction  in  the  ability  to  see 
significant  objects  or  both  due  to  an  unsuitable 
distribution  or  range  of  luminance  or  due  to  extreme 
contrasts  in  space  and  time. 

2.1.15  Illuminance — At  a  point  on  a  surface,  the  ratio 
of  the  luminous  flux  incident  on  an  infinitesimal  element 
of  the  surface  containing  the  point  under  consideration 
to  the  area  of  the  element. 

NOTE  —  The  unit  of  illuminance  (the  measurement  of 
illumination)  is  lux  which  is  1  lumen  per  m2. 

2.1.16  Internal  Reflected  Component  (IRC)  —  The 
ratio  (or  percentage)  of  that  part  of  the  daylight 
illuminance  at  a  point  in  a  given  plane  which  is  received 
by  direct  reflection  or  inter-reflection  from  the  internal 
surfaces  as  compared  to  the  simultaneous  exterior 
illuminance  on  a  horizontal  plane  due  to  the  entire 
hemisphere  of  an  unobstructed  clear  design  sky. 

2.1.17  Light  Output  Ratio  (LOR)  or  Efficiency  (r|)  — 
The  ratio  of  the  luminous  flux  emitted  from  the 
luminaire  to  that  emitted  from  the  lamp(s)  (nominal 
luminous  flux).  It  is  expressed  in  percent. 

2.1.18  Light  Pipe  —  A  conduit  made  of  a  highly 
reflective  material,  which  is  capable  of  channeling  light 
from  one  end  to  the  other  through  successive  internal 
reflections.  Such  a  pipe  may  be  flexible  or  rigid. 

2.1.19  Light  Shelf  —  A  daylighting  system  based  on 
sun  path  geometry  used  to  bounce  the  light  off  a  ceiling, 
project  it  deeper  into  a  space,  distribute  it  from  above, 
and  diffuse  it  to  produce  a  uniform  light  level  below. 

2.1.20  Lumen  (lm)  —  SI  unit  of  luminous  flux.  The 
luminous  flux  emitted  within  unit  solid  angle  (one 
steradian)  by  a  point  source  having  a  uniform  intensity 
of  one  candela. 

2.1.21  Luminance  (At  a  point  of  a  Surface  in  a  Given 
Direction)  ( Brightness )  —  The  quotient  of  the  luminous 
intensity  in  the  given  direction  of  an  infinitesimal 
element  of  the  surface  containing  the  point  under 
consideration  by  the  orthogonally  projected  area  of  the 
element  on  a  plane  perpendicular  to  the  given  direction. 
The  unit  is  candela  per  square  metre  (cd/m2). 

2.1.22  Luminous  Flux  (<|))  —  The  quantity 
characteristic  of  radiant  flux  which  expresses  its 
capacity  to  produce  visual  sensation  evaluated 
according  to  the  values  of  relative  luminous  efficiency 
for  the  light  adapted  eye: 


a)  Effective  Luminous  Flux  (c|)n)  —  Total  luminous 
flux  which  reaches  the  working  plane. 

b)  Nominal  Luminous  Flux  (c|)o)  —  Total  luminous 
flux  of  the  light  sources  in  the  interior. 

2.1.23  Maintenance  Factor  (d)  —  The  ratio  of  the 
average  illuminance  on  the  working  plane  after  a  certain 
period  of  use  of  a  lighting  installation  to  the  average 
illuminance  obtained  under  the  same  conditions  for  a 
new  installation. 

2.1.24  Meridian  —  It  is  the  great  circle  passing  through 
the  zenith  and  nadir  for  a  given  point  of  observation. 

2.1.25  North  and  South  Points  —  The  point  in  the 
respective  directions  where  the  meridian  cuts  the 
horizon. 

2.1.26  Orientation  of  Buildings  —  In  the  case  of  non¬ 
square  buildings,  orientation  refers  to  the  direction  of 
the  normal  to  the  long  axis.  For  example,  if  the  length  of 
the  building  is  east-west,  its  orientation  is  north-south. 

2.1.27  Peripheral  Field  —  It  is  the  rest  of  the  visual 
field  which  enables  the  observer  to  be  aware  of  the 
spatial  framework  surrounding  the  object  seen. 

NOTE  —  A  central  part  of  the  peripheral  field,  subtending  an 
angle  of  about  30°  on  either  side  of  the  point  of  fixation,  is 
chiefly  involved  in  the  perception  of  glare. 

2.1.28  Reflected  Glare  —  The  variety  of  ill  effects  on 
visual  efficiency  and  comfort  produced  by  unwanted 
reflections  in  and  around  the  task  area. 

2.1.29  Reflection  Factor  (Reflectance)  —  The  ratio 
of  the  luminous  flux  reflected  by  a  body  (with  or  without 
diffusion)  to  the  flux  it  receives.  Some  symbols  used 
for  reflection  factor  are: 

rc  =  reflection  factor  of  ceiling. 
rw  =  reflection  factor  of  parts  of  the  wall  between 
the  working  surface  and  the  luminaires. 

rf  =  reflection  factor  of  floor. 

2.1.30  Reveal —  The  side  of  an  opening  for  a  window. 

2.1.31  Room  Index  (kr)  —  An  index  relating  to  the 
shape  of  a  rectangular  interior,  according  to  the  formula: 

k  — 

*  ~  (L  +  W)Hm 

where  L  and  W  are  the  length  and  width  respectively  of 
the  interior,  and  Hm  is  the  mounting  height,  that  is, 
height  of  the  fittings  above  the  working  plane. 

NOTES 

1  For  rooms  where  the  length  exceeds  5  times  the  width,  L 
shall  be  taken  as  L  =  5  W. 

2  If  the  reflection  factor  of  the  upper  stretch  of  the  walls  is  less 
than  half  the  reflection  factor  of  the  ceiling,  for  indirect  or  for 
the  greater  part  of  indirect  lighting,  the  value  Hm  is  measured 
between  the  ceiling  and  the  working  plane. 


6 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


2.1.32  Sky  Component  (SC)  —  The  ratio  (or 
percentage)  of  that  part  of  the  daylight  illuminance  at  a 
point  on  a  given  plane  which  is  received  directly  from 
the  sky  as  compared  to  the  simultaneous  exterior 
illuminance  on  a  horizontal  plane  from  the  entire 
hemisphere  of  an  unobstructed  clear  design  sky. 

2.1.33  Solar  Load  —  The  amount  of  heat  received 
into  a  building  due  to  solar  radiation  which  is  affected 
by  orientation,  materials  of  construction  and  reflection 
of  external  finishes  and  colour. 

2.1.34  Utilization  Factor  (Coefficient  of  Utilization) 
(p)  —  The  ratio  of  the  total  luminous  flux  which  reaches 
the  working  plane  (effective  luminous  flux,  <|>n)  to  the 
total  luminous  flux  of  the  light  sources  in  the  interior 
(nominal  luminous  flux,  (f>0). 

2.1.35  Visual  Field  —  The  visual  field  in  the  binocular 
which  includes  an  area  approximately  120°  vertically 
and  160°  horizontally  centering  on  the  point  to  which 
the  eyes  are  directed.  The  line  joining  the  point  of 
fixation  and  the  centre  of  the  pupil  of  each  eye  is  called 
its  primary  line  of  sight. 

2.1.36  Working  Plane  —  A  horizontal  plane  at  a  level 
at  which  work  will  normally  be  done  ( see  4. 1.4.3 
and  4. 1.4.4). 

2.2  Ventilation 

2.2.1  Air  Change  per  Hour  —  The  amount  of  air 
leakage  into  or  out  of  a  building  or  room  in  terms  of 
the  number  of  times  the  building  volume  or  room 
volume  exchanged. 

2.2.2  Axial  Flow  Fan  —  A  fan  having  a  casing  in  which 
the  air  enters  and  leaves  the  impeller  in  a  direction 
substantially  parallel  to  its  axis. 

2.2.3  Centrifugal  Fan  —  A  fan  in  which  the  air  leaves 
the  impeller  in  a  direction  substantially  at  right  angles 
to  its  axis. 

2.2.4  Contaminants  —  Dusts,  fumes,  gases,  mists, 
vapours  and  such  other  substances  present  in  air  that 
are  likely  to  be  injurious  or  offensive  to  the  occupants. 


2.2.8  Exhaust  of  Air — Removal  of  air  from  a  building 
or  a  room  and  its  disposal  outside  by  means  of  a 
mechanical  device,  such  as  a  fan. 

2.2.9  Fresh  Air  or  Outside  Air  —  Air  of  that  quality, 
which  meets  the  criteria  of  Table  1  and  in  addition 
shall  be  such  that  the  concentration  of  any  contaminant 
in  the  air  is  limited  to  within  one-tenth  the  threshold 
limit  value  (TLV)  of  that  contaminant. 

NOTES 

1  Where  it  is  reasonably  believed  that  the  air  of  quality  is  not 
expected  as  indicated  above,  sampling  and  analysis  shall  be 
carried  out  by  a  competent  authority  having  jurisdiction  and  if 
the  outside  air  of  the  specified  quality  is  not  available,  filtration 
and  other  treatment  devices  shall  be  used  to  bring  its  quality  to 
or  above  the  levels  mentioned  in  Table  1 . 

Odour  is  to  be  essentially  unobjectionable. 

2  The  above  list  of  contaminants  is  not  exhaustive  and  available 
special  literature  may  be  referred  for  data  on  other  contaminants. 


Table  1  Maximum  Allowable  Contaminant 
Concentrations  for  Ventilation  Air 

( Clause  2.2.9) 


SI 

Contaminants 

Annual 

Short 

Averaging 

No. 

Average 

Term  Level 

Period 

(Arithmetic 

(Not  to 

Mean) 

Exceed 
More  than 

Once  a 
Year) 

Hg/m3 

Hg/m3 

h 

(1) 

(2) 

(3) 

(4) 

(2) 

i)  Suspended 

60 

150 

24 

particulates 

ii)  Sulphur  oxides 

80 

400 

24 

iii)  Carbon  monoxide 

20  000 

30  000 

8 

iv)  Photochemical 

100 

500 

1 

oxidant 

v)  Hydrocarbons  (not 

1  800 

4  000 

3 

including  methanes) 

vi)  Nitrogen  oxide 

200 

500 

24 

2.2.10  General  Ventilation  —  Ventilation,  either 
natural  or  mechanical  or  both,  so  as  to  improve  the 
general  environment  of  the  building,  as  opposed  to  local 
exhaust  ventilation  for  contamination  control. 


2.2.5  Dilution  Ventilation  —  Supply  of  outside  air  to 
reduce  the  airborne  concentration  of  contaminants  in 
the  building. 

2.2.6  Dry  Bulb  Temperature  —  The  temperature  of 
the  air,  read  on  a  thermometer,  taken  in  such  a  way  so 
as  to  avoid  errors  due  to  radiation. 


2.2.11  Globe  Temperature  —  The  temperature 
measured  by  a  thermometer  whose  bulb  is  enclosed  in 
a  matt  black  painted  thin  copper  globe  of  150  mm 
diameter.  It  combines  the  influence  of  air  temperature 
and  thermal  radiations  received  or  emitted  by  the 
bounding  surfaces. 


2.2.7  Effective  Temperature  (ET)  —  An  arbitrary  index 
which  combines  into  a  single  value  the  effect  of 
temperature,  humidity  and  air  movement  on  the 
sensation  of  warmth  or  cold  felt  by  the  human  body 
and  its  numerical  value  is  that  of  the  temperature  of 
still  saturated  air  which  would  induce  an  identical 
sensation. 


2.2.12  Humidification  —  The  process  whereby  the 
absolute  humidity  of  the  air  in  a  building  is  maintained 
at  a  higher  level  than  that  of  outside  air  or  at  a  level 
higher  than  that  which  would  prevail  naturally. 

2.2.13  Humidity,  Absolute — The  mass  of  water  vapour 
per  unit  volume. 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


7 


2.2.14  Humidity,  Relative  —  The  ratio  of  the  partial 
pressure  or  density  of  the  water  vapour  in  the  air  to  the 
saturated  pressure  or  density,  respectively  of  water 
vapour  at  the  same  temperature. 

2.2.15  Local  Exhaust  Ventilation  —  Ventilation  effected 
by  exhaust  of  air  through  an  exhaust  appliance,  such  as 
a  hood  with  or  without  fan  located  as  closely  as  possible 
to  the  point  at  which  contaminants  are  released,  so  as  to 
capture  effectively  the  contaminants  and  convey  them 
through  ducts  to  a  safe  point  of  discharge. 

2.2.16  Make-Up  Air  —  Outside  air  supplied  into  a 
building  to  replace  the  indoor  air. 

2.2.17  Mechanical  Ventilation  —  Supply  of  outside 
air  either  by  positive  ventilation  or  by  infiltration  by 
reduction  of  pressure  inside  due  to  exhaust  of  air,  or  by 
a  combination  of  positive  ventilation  and  exhaust  of 
air. 

2.2.18  Natural  Ventilation  —  Supply  of  outside  air 
into  a  building  through  window  or  other  openings  due 
to  wind  outside  and  convection  effects  arising  from 
temperature  or  vapour  pressure  differences  (or  both) 
between  inside  and  outside  of  the  building. 

2.2.19  Positive  Ventilation  —  The  supply  of  outside 
air  by  means  of  a  mechanical  device,  such  as  a  fan. 

2.2.20  Propeller  Fan  —  A  fan  in  which  the  air  leaves 
the  impeller  in  a  direction  substantially  parallel  to  its 
axis  designed  to  operate  normally  under  free  inlet  and 
outlet  conditions. 

2.2.21  Spray-Head  System  —  A  system  of  atomizing 
water  so  as  to  introduce  free  moisture  directly  into  a 
building. 

2.2.22  Stack  Effect  —  Convection  effect  arising  from 
temperature  or  vapour  pressure  difference  (or  both) 
between  outside  and  inside  of  the  room  and  the  difference 
of  height  between  the  outlet  and  inlet  openings. 

2.2.23  Tropical  Summer  Index  (TSI)  —  The 
temperature  of  calm  air  at  50  percent  relative  humidity 
which  imparts  the  same  thermal  sensation  as  the  given 
environment. 

2.2.24  Threshold  Limit  Value  (TLV)  —  Refers  to  airborne 
concentration  of  contaminants  currently  accepted  by  the 
American  Conference  of  Governmental  Industrial 
Hygienists  and  represents  conditions  under  which  it  is 
believed  that  nearly  all  occupants  may  be  repeatedly 
exposed,  day  after  day,  without  adverse  effect. 

2.2.25  Velocity,  Capture  —  Air  velocity  at  any  point 
in  front  of  the  exhaust  hood  necessary  to  overcome 
opposing  air  currents  and  to  capture  the  contaminants 
in  air  at  that  point  by  causing  the  air  to  flow  into  the 
exhaust  hood. 


2.2.26  Ventilation  —  Supply  of  outside  air  into,  or  the 
removal  of  inside  air  from  an  enclosed  space. 

2.2.27  Wet  Bulb  Temperature  —  The  steady 
temperature  finally  given  by  a  thermometer  having  its 
bulb  covered  with  gauze  or  muslin  moistened  with 
distilled  water  and  placed  in  an  air  stream  of  not  less 
than  4.5  m/s. 

3  ORIENTATION  OF  BUILDING 

3.1  The  chief  aim  of  orientation  of  buildings  is  to 
provide  physically  and  psychologically  comfortable 
living  inside  the  building  by  creating  conditions  which 
suitably  and  successfully  ward  off  the  undesirable 
effects  of  severe  weather  to  a  considerable  extent  by 
judicious  use  of  the  recommendations  and  knowledge 
of  climatic  factors. 

3.2  Basic  Zones 

3.2.1  For  the  purpose  of  design  of  buildings,  the 
country  may  be  divided  into  the  major  climatic  zones 
as  given  in  Table  2,  which  also  gives  the  basis  of  this 
classification. 


Table  2  Classification  of  Climate 

(' Clause  3.2.1) 


SI 

Climatic  Zone 

Mean  Monthly 

Mean  Monthly 

No. 

Maximum 

Relative 

Temperature 

Humidity 

°C 

Percent 

(1) 

(2) 

(3) 

(4) 

i) 

Hot-dry 

Above  30 

Below  55 

ii) 

Warm-humid 

Above  30 

Above  55 

Above  25 

Above  75 

iii) 

Temperate 

25-30 

Below  75 

iv) 

Cold 

Below  25 

All  values 

v) 

Composite 

see  3.2.2 

The  climatic  classification  map  of  India  is  shown  in 
Fig.  2. 

3.2.2  Each  climatic  zone  does  not  have  same  climate 
for  the  whole  year;  it  has  a  particular  season  for  more 
than  six  months  and  may  experience  other  seasons  for 
the  remaining  period.  A  climatic  zone  that  does  not  have 
any  season  for  more  than  six  months  may  be  called  as 
composite  zone. 

3.3  Climatic  Factors 

From  the  point  of  view  of  lighting  and  natural 
ventilation,  the  following  climatic  factors  influence  the 
optimum  orientation  of  the  building: 

a)  Solar  radiation  and  temperature, 

b)  Relative  humidity,  and 

c)  Prevailing  winds. 


8 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Based  upon  Survey  of  India  Political  map  printed  in  2002.  (c)  Government  of  India  Copyright,  2016 

The  territorial  waters  of  India  extend  into  the  sea  to  a  distance  of  twelve  nautical  miles  measured  from  the  appropriate  baseline. 

The  interstate  boundaries  between  Arunachal  Pradesh,  Assam  and  Meghalaya  shown  on  this  map  are  as  interpreted 
from  the  North-Eastern  Areas  (Reorganization)  Act,  1971 ,  but  have  yet  to  be  verified. 

The  external  boundaries  and  coastlines  of  India  agree  with  the  Record/Master  Copy  certified  by  Survey  of  India. 

The  responsibility  for  the  correctness  of  internal  details  rest  with  the  publisher. 

Fig.  2  Climatic  Zones  of  India 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


9 


3.4  Solar  Radiation 

3.4.1  The  best  orientation  from  solar  point  of  view 
requires  that  the  building  as  a  whole  should  receive  the 
maximum  solar  radiation  in  winter  and  the  minimum 
in  summer.  For  practical  evaluation,  it  is  necessary  to 
know  the  duration  of  sunshine,  and  hourly  solar 
intensity  on  the  various  external  surfaces  on 
representative  days  of  the  seasons.  The  total  direct  plus 
diffused  diurnal  solar  loads  per  unit  area  on  vertical 
surface  facing  different  directions  are  given  in  Table  3 
for  two  days  in  the  year,  that  is,  22  June  and  22 
December,  representative  of  summer  and  winter,  for 
latitudes  corresponding  to  some  important  cities  all  over 
India.  From  Table  3,  the  total  heat  intake  can  be 
calculated  for  all  possible  orientations  of  the  building 
for  these  extreme  days  of  summer  and  winter.  Solar 
load  on  vertical  surfaces  of  different  orientation  can 
be  calculated  as  per  the  method  given  in  Annex  A. 

3.4.1.1  Except  in  cold  climatic  zone,  suitable  sun-breakers 
have  to  be  provided  to  cut  off  the  incursion  of  direct 
sunlight  to  prevent  heat  radiation  and  to  avoid  glare. 

3.5  Relative  Humidity  and  Prevailing  Winds 

3.5.1  The  discomfort  due  to  high  relative  humidity  in 
air  when  temperatures  are  also  high  can  be 
counteracted,  to  a  great  extent,  by  circulation  of  air 
with  electric  fans  or  by  ventilation.  In  the  past, 
simultaneously  with  heavy  construction  and 
surrounding  Verandahs  to  counter  the  effect  of  sun’s 
radiation,  there  was  also  an  over  emphasis  on  prevailing 
winds  to  minimise  the  adverse  effects  of  high  humidity 


with  high  temperatures.  With  the  introduction  of  electric 
fan  to  effectively  circulate  air  and  owing  to  taking  into 
account  the  rise  in  cost  of  construction  of  buildings, 
emphasis  should  be  placed  on  protection  from  solar 
radiation  where  temperatures  are  very  high.  When, 
however,  there  is  less  diurnal  variation  between 
morning  and  mean  maximum  temperatures  along  with 
high  humidity,  as  in  coastal  areas,  the  emphasis  should 
be  on  prevailing  winds. 

3.5.1. 1  For  the  purpose  of  orientation,  it  is  necessary 
to  study  the  velocity  and  direction  of  the  wind  at  each 
hour  and  in  each  month  instead  of  relying  on 
generalizations  of  a  month  or  a  period  or  for  the  year 
as  a  whole.  This  helps  to  spot  the  right  winds  for  a 
particular  period  of  day  or  night. 

3. 5.1.2  It  is  generally  found  that  variation  up  to  30° 
with  respect  to  the  prevalent  wind  direction  does  not 
materially  affect  indoor  ventilation  (average  indoor  air 
speed)  inside  the  building. 

3.5.2  In  hot-dry  climate,  advantage  can  be  taken  of 
evaporative  cooling  in  summer  to  cool  the  air  before 
introducing  it  into  the  building.  But  in  warm  humid 
climate,  it  is  desirable  either  to  regulate  the  rate  of  air 
movement  with  the  aid  of  electric  fans  or  to  take 
advantage  of  prevailing  winds. 

3.6  Aspects  of  Daylighting 

Since  the  clear  design  sky  concept  for  daylighting  takes 
care  of  the  worst  possible  situation,  orientation  is  not  a 
major  problem  for  daylighting  in  buildings,  except  that 


Table  3  Total  Solar  Radiation  (Direct  Plus  Diffused)  Incident  on  Various  Surfaces  of 
Buildings,  in  W/m2/day,  for  Summer  and  for  Winter  Seasons 

( Clause  3.4.1) 

SI  Orientation  Latitude 

No.  _ _ _ 


(1)  (2) 


i) 

North 

Summer 

Winter 

ii) 

North-East 

Summer 

Winter 

iii) 

East 

Summer 

Winter 

iv) 

South-East 

Summer 

Winter 

v) 

South 

Summer 

Winter 

vi) 

South-West 

Summer 

Winter 

vii) 

West 

Summer 

Winter 

viii) 

North-West 

Summer 

Winter 

ix) 

Horizontal 

Summer 

Winter 

9°N 

(3) 

13°N 

(4) 

17°N 

(5) 

1494 

1  251 

2  102 

873 

859 

840 

2  836 

2  717 

3  144 

1  240 

1  158 

1  068 

3  344 

3  361 

3  475 

2  800 

2  673 

2  525 

2  492 

2  660 

2  393 

3  936 

3  980 

3  980 

1  009 

1  185 

1  035 

4  674 

4  847 

4  958 

2  492 

2  660 

2  393 

3  936 

3  980 

3  980 

3  341 

3  361 

3  475 

2  800 

2  673 

2  525 

2  836 

2  717 

3  144 

1  240 

1  158 

1  068 

8  107 

8  139 

8  379 

6  409 

6  040 

5615 

21°N 

(6) 

25  °N 
(7) 

29°N 

(8) 

1  775 

2  173 

1  927 

825 

802 

765 

3  092 

3  294 

3  189 

1  001 

912 

835 

3  598 

3  703 

3  794 

2  409 

2211 

2  055 

2  629 

2  586 

2  735 

3  995 

3  892 

3  818 

1  117 

1  112 

1  350 

5  059 

4  942 

4981 

2  629 

2  586 

2  735 

3  995 

3  892 

3  818 

3  598 

3  703 

3  794 

2  409 

2211 

2  055 

3  092 

3  294 

3  189 

1  001 

912 

835 

8  553 

8  817 

8  863 

5  231 

4  748 

4281 

10 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


direct  sunshine  and  glare  should  be  avoided.  However, 
due  allowance  should  be  given  to  the  mutual  shading 
effects  of  opposite  facades. 

3.7  Planting  of  Trees 

Planting  of  trees  in  streets  and  in  open  spaces  should  be 
done  carefully  to  take  advantage  of  both  shades  and 
sunshine  without  handicapping  the  flow  of  natural  winds. 
Their  advantage  in  abating  glare  and  in  providing  cool 
and/or  warm  pockets  in  developed  areas  should  also  be 
taken.  Some  trees  shed  leaves  in  winter  while  retaining 
thick  foliage  in  summer.  Such  trees  will  be  very 
advantageous,  particularly  where  southern  and  western 
exposures  are  concerned,  by  allowing  maximum  sun 
during  winter  and  effectively  blocking  it  in  summer. 

3.8  For  detailed  information  regarding  orientation  of 
buildings  and  recommendations  for  various  climatic 
zones  of  country,  reference  may  be  made  to  good 
practice  [8-1(1)]. 

4  LIGHTING 

4.1  Principles  of  Lighting 

4.1.1  Aims  of  Good  Lighting 

Good  lighting  is  necessary  for  all  buildings  and  has 
three  primary  aims.  The  first  aim  is  to  promote  work 
and  other  activities  carried  out  within  the  building;  the 
second  aim  is  to  promote  the  safety  of  the  people  using 
the  building;  and  the  third  aim  is  to  create,  in 
conjunction  with  the  structure  and  decoration,  a 
pleasing  environment  conducive  to  interest  of  the 
occupants  and  a  sense  of  their  well-being. 

4.1. 1.1  Realization  of  these  aims  involves  the  following: 

a)  Careful  planning  of  the  brightness  and  colour 
pattern  within  both  the  working  areas  and  the 
surroundings  so  that  attention  is  drawn  naturally 
to  the  important  areas,  detail  is  seen  quickly 
and  accurately  and  the  room  is  free  from  any 
sense  of  gloom  or  monotony  ( see  4.1.4); 

b)  Using  directional  lighting,  where  appropriate, 
to  assist  perception  of  task  detail  and  to  give 
good  modeling; 

c)  Controlling  direct  and  reflected  glare  from 
light  sources  to  eliminate  visual  discomfort; 

d)  In  artificial  lighting  installations,  minimizing 
flicker  from  certain  types  of  lamps  and  paying 
attention  to  the  colour  rendering  properties  of 
the  light; 

e)  Correlating  lighting  throughout  the  building  to 
prevent  excessive  differences  between  adjacent 
areas  so  as  to  reduce  the  risk  of  accidents;  and 

f)  Installing  emergency  lighting  systems,  where 
necessary. 


4.1.2  Planning  the  Brightness  Pattern 

The  brightness  pattern  seen  within  an  interior  may  be 
considered  as  composed  of  three  main  parts  —  the  task 
itself,  immediate  background  of  the  task  and  the  general 
surroundings  of  walls,  ceiling,  floor,  equipment  and 
furnishings. 

4.1.2.1  In  occupations  where  the  visual  demands  are 
small,  the  levels  of  illumination  derived  from  a  criterion 
of  visual  performance  alone  may  be  too  low  to  satisfy 
the  other  requirements.  For  such  situations,  therefore, 
illuminance  recommendations  are  based  on  standards 
of  welfare,  safety  and  amenity  judged  appropriate  to  the 
occupations;  they  are  also  sufficient  to  give  these  tasks 
brightness  which  ensured  that  the  visual  performance 
exceeds  the  specified  minimum.  Unless  there  are  special 
circumstances  associated  with  the  occupation,  it  is 
recommended  that  the  illuminance  of  all  working  areas 
within  a  building  should  generally  be  150  lux. 

4. 1.2.2  Where  work  takes  place  over  the  whole 
utilizable  area  of  room,  the  illumination  over  that  area 
should  be  reasonably  uniform  and  it  is  recommended 
that  the  uniformity  ratio  (minimum  illuminance  divided 
by  average  illuminance  levels)  should  be  not  less  than 
0.7  for  the  working  area. 

4.1.2.3  When  the  task  brightness  appropriate  to  an 
occupation  has  been  determined,  the  brightness  of  the 
other  parts  of  the  room  should  be  planned  to  give  a 
proper  emphasis  to  visual  comfort  and  interest. 

A  general  guide  for  the  brightness  relationship  within 
the  normal  field  of  vision  should  be  as  follows: 

a)  For  high  task  brightness  Maximum 

(above  100  cd/m2): 

1)  Between  the  visual  task  and  3 : 1 

the  adjacent  areas  like  table  tops 

2)  Between  the  visual  task  and  10:1 
the  remote  areas  of  the  room 

b)  For  low  and  medium  task  brightness  (below 
100  cd/m2):  The  task  should  be  brighter  than 
both  the  background  and  the  surroundings;  the 
lower  the  task  brightness,  the  less  critical  is 
the  relationship. 

4.1.2.4  In  case  of  all  buildings  and  facilities  open  to 
and  used  by  the  public  including  all  forms  of  public 
housing  by  the  government/civic  bodies  and  private 
developers,  the  requirements  for  visual  contrast  as  given 
in  13  and  Annex  B  of  Part  3  ‘Development  Control 
and  Rules  and  General  Building  Requirements’  of  the 
Code  shall  also  be  complied  with  for  ensuring  visual 
comfort  for  elders  and  persons  with  disabilities. 

4.1.3  Glare 

Excessive  contrast  or  abrupt  and  large  changes  in 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


11 


brightness  produce  the  effect  of  glare.  When  glare  is 
present,  the  efficiency  of  vision  is  reduced  and  small 
details  or  subtle  changes  in  scene  cannot  be  perceived. 
It  may  be, 

a)  direct  glare  due  to  light  sources  within  the  field 
of  vision; 

b)  reflected  glare  due  to  reflections  from  light 
sources  or  surfaces  of  excessive  brightness; 
and 

c)  veiling  glare  where  the  peripheral  field  is 
comparatively  very  bright. 

4. 1.3.1  An  example  of  glare  sources  in  day  lighting  is 
the  view  of  the  bright  sky  through  a  window  or  skylight, 
especially  when  the  surrounding  wall  or  ceiling  is 
comparatively  dark  or  weakly  illuminated.  Glare  can 
be  minimised  in  this  case  either  by  shielding  the  open 
sky  from  direct  sight  by  louvers,  external  hoods  or  deep 
reveals,  curtains  or  other  shading  devices  or  by  cross 
lighting  the  surroundings  to  a  comparable  level.  A 
gradual  transition  of  brightness  from  one  portion  to  the 
other  within  the  field  of  vision  always  avoids  or 
minimises  the  discomfort  from  glare. 

For  electric  lamps  the  minimum  shielding  angles  for 
lamp  luminance  shall  not  be  less  than  the  values  given 
in  the  table  below: 


Lamp  Luminance  Minimum  Shielding  Angle 
kcd/m2  Degree 

1  to  20  10 

20  to  50  15 

50  to  500  20 

>  500  30 

The  above  mentioned  shielding  angle  should  not  be 
applied  to  luminaires  that  do  not  appear  in  the  field  of 
view  of  a  worker  during  usual  work  and/or  do  not  give 
the  worker  any  noticeable  disability  glare. 

Table  4  also  gives  recommended  value  of  quality  class 
of  direct  glare  limitation  for  different  tasks.  These  are 
numbers  assigned  to  qualitative  limits  of  direct  glare: 
high,  medium  and  low  quality  as  1, 2  and  3,  respectively. 
For  more  details  reference  may  be  made  to  good 
practice  [8-1(2)]. 

4.1.4  Recommended  Values  of  Illuminance 

Table  4  gives  recommended  values  of  illuminance 
commensurate  with  the  general  standards  of  lighting 
described  in  this  Section  and  related  to  many 
occupations  and  buildings.  These  are  valid  under  most 
of  the  conditions  whether  the  illumination  is  by 
day  lighting,  artificial  lighting  or  a  combination  of  the 
two.  The  great  variety  of  visual  tasks  makes  it 
impossible  to  list  them  all  and  those  given  should  be 
regarded  as  representing  types  of  task. 


4.1.4. 1  The  different  locations  and  tasks  are  grouped 
within  the  following  four  sections: 

a)  Industrial  buildings  and  process; 

b)  Offices,  schools  and  public  buildings; 

c)  Surgeries  and  hospitals;  and 

d)  Hotels,  restaurants,  shops  and  homes. 

4. 1.4. 2  The  illumination  levels  recommended  in 
Table  4  are  those  to  be  maintained  at  all  time  on  the 
task.  As  circumstances  may  be  significantly  different 
for  different  interiors  used  for  the  same  application  or 
for  different  conditions  for  the  same  kind  of  activity,  a 
range  of  illuminances  is  recommended  for  each  type 
of  interior  or  activity  instead  of  a  single  value  of 
illuminance.  Each  range  consists  of  three  successive 
steps  of  the  recommended  scale  of  illuminances.  They 
represent  good  practice  and  should  be  regarded  as 
giving  order  of  illumination  commonly  required  rather 
than  as  having  some  absolute  significance.  For  working 
interiors  the  middle  value  of  each  range  represents  the 
recommended  service  illuminance  that  would  be  used 
unless  one  or  more  of  the  factors  mentioned  below 
apply. 

4.1.4.2.1  The  higher  value  of  the  range  should  be  used 
when, 

a)  unusually  low  reflectances  or  contrasts  are 
present  in  the  task; 

b)  errors  are  costly  to  rectify; 

c)  visual  work  is  critical; 

d)  accuracy  or  higher  productivity  is  of  great 
importance;  and 

e)  visual  capacity  of  the  worker  makes  it 
necessary. 

4.1.4.2.2  The  lower  value  of  the  range  may  be  used  when, 

a)  reflectances  or  contrast  are  unusually  high; 

b)  speed  and  accuracy  is  not  important;  and 

c)  the  task  is  executed  only  occasionally. 

4.1.4.3  Where  a  visual  task  is  required  to  be  carried 
out  throughout  an  interior,  general  illumination  level 
to  the  recommended  value  on  the  working  plane  is 
necessary;  where  the  precise  height  and  location  of  the 
task  are  not  known  or  cannot  be  easily  specified,  the 
recommended  value  is  that  on  horizontal  plane  850  mm 
above  floor  level. 

NOTE  —  For  an  industrial  task,  working  plane  for  the  purpose 
of  general  illumination  levels  is  that  on  a  work  place  which  is 
generally  750  mm  above  the  floor  level.  For  certain  purposes, 
such  as  viewing  the  objects  of  arts,  the  illumination  levels 
recommended  are  for  the  vertical  plane  at  which  the  art  pieces 
are  placed. 

4.1.4.4  Where  the  task  is  localized,  the  recommended 
value  is  that  for  the  task  only;  it  need  not,  and  sometimes 
should  not,  be  the  general  level  of  illumination  used 


12 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


throughout  the  interior.  Some  processes,  such  as 
industrial  inspection  process,  call  for  lighting  of 
specialized  design,  in  which  case  the  level  of  illumination 
is  only  one  of  the  several  factors  to  be  taken  into  account. 

4.1.4. 5  In  case  of  all  buildings  and  facilities  open  to 
and  used  by  the  public,  including  all  forms  of  public 
housing  by  the  government/civic  bodies  and  private 
developers,  the  minimum  luminance  level  as  given  in 
13  and  Annex  B  of  Part  3  'Development  Control  Rules 
and  General  Building  Requirements'  of  the  Code  shall 
also  be  complied  with  for  ensuring  sufficient  lighting 
for  accessibility  by  elders  and  persons  with  disabilities. 

4.1.5  Lighting  for  Movement  About  a  Building 

Most  buildings  are  complexes  of  working  areas  and 
other  areas,  such  as  passages,  corridors,  stairways, 
lobbies  and  entrances.  The  lighting  of  all  these  areas 
shall  be  properly  correlated  to  give  safe  movement 
within  the  building  at  all  times. 

In  case  of  all  buildings  and  facilities  open  to  and  used 
by  the  public,  including  all  forms  of  public  housing  by 
the  govemment/civic  bodies  and  private  developers,  the 
illuminance  in  these  areas  shall  comply  with 
requirements  given  in  13  and  Annex  B  of  Part  3 
‘Development  Control  Rules  and  General  Building 
Requirements’  of  the  Code. 

4.1.5. 1  Corridors,  passages  and  stairways 

Accidents  may  result  if  people  leave  a  well-lighted 
working  area  and  pass  immediately  into  corridors  or 
on  to  stairways  where  the  lighting  is  inadequate,  as  the 
time  needed  for  adaptation  to  the  lower  level  may  be 
too  long  to  permit  obstacles  or  the  treads  of  stairs  to  be 
seen  sufficiently  quickly.  For  the  same  reason,  it  is 
desirable  that  the  illumination  level  of  rooms  which 
open  off  a  working  area  should  be  fairly  high  even 
though  the  rooms  may  be  used  only  occasionally. 

It  is  important,  when  lighting  stairways,  to  prevent 
disability  from  glare  caused  by  direct  sight  of  bright 
sources  to  emphasize  the  edges  of  the  treads  and  to 
avoid  confusing  shadows.  The  same  precautions  should 
be  taken  in  the  lighting  of  catwalks  and  stairways  on 
outdoor  industrial  plants. 

4.1.5.2  Entrances 

The  problems  of  correctly  grading  the  lighting  within 
a  building  to  allow  adequate  time  for  adaptation  when 
passing  from  one  area  to  another  area  are  particularly 
acute  at  building  entrances.  These  are  given  below: 

a)  By  day,  people  entering  a  building  will  be 
adapted  to  the  very  high  levels  of  brightness 
usually  present  outdoors  and  there  is  risk  of 
accident  if  entrance  areas,  particularly  any 
steps,  are  poorly  lighted.  This  problem  may 
often  be  overcome  by  arranging  windows  to 


give  adequate  natural  lighting  at  the  immediate 
entrance,  grading  to  lower  levels  further  inside 
the  entrance  area.  Where  this  cannot  be  done, 
supplementary  artificial  lighting  should  be 
installed  to  raise  the  level  of  illumination  to 
an  appropriate  value. 

b)  At  night  it  is  desirable  to  light  entrance  halls  and 
lobbies  so  that  the  illumination  level  reduces 
towards  the  exit  and  so  that  no  bright  fittings  are 
in  the  line  of  sight  of  people  leaving  the  building. 
Any  entrance  steps  to  the  building  should  be 
well-lighted  by  correctly  screened  fittings. 

4.1.6  Colour  Rendering 

The  colour  appearance  of  light  and  its  colour  rendering 
capability  are  different  aspects  of  the  light  sources.  A 
faithful  reproduction  of  an  object  colour  depends  on 
the  colour  rendering  capability  of  the  light  source.  In 
1965  International  Commission  on  Illumination  (CIE) 
developed  a  quantitative  method  of  assignment  of 
colour  rendering  property,  and  is  denoted  as  Colour 
Rendering  Index  (CRI). 

CRI  is  arrived  at  by  a  test  by  which  a  number  of  specified 
samples  are  tested  under  a  standard  or  reference  light 
source  and  the  chromaticity  coordinate  are  plotted  on 
the  IE  triangle  as  given  in  Fig.  7  of  Part  2  ‘Physics  of 
Light,  Section  3  Colour’  of  National  Lighting  Code  2010. 
The  same  test  is  repeated  under  the  source  under  test 
and  corresponding  chromaticity  coordinate  are  plotted 
on  the  same  plot.  The  difference  between  the  position  of 
each  sample  for  test  and  standard  source  is  measured  to 
scale.  The  general  colour  rendering  index  (Ra)  is 
obtained  by  the  average  value  for  eight  samples  (see 
Fig.  8  of  Part  2  ‘Physics  of  Light,  Section  3  Colour’  of 
National  Lighting  Code  2010).  For  perfect  agreement 
of  colour,  the  R1  value  should  be  100.  In  general: 

Ra  =  1/  (R1  +  R2  +  R3  +  R4  + . +  R8) 

The  specific  colour  rendering  index  for  an  individual 
sample  is  given  by: 

Ri  =  100  -  4.6AEi 

where 

AEi  =  chromaticity  shift  on  the  CIE  chromaticity 
diagram  for  each  sample. 

From  the  obtained  value  of  Ra,  as  calculated  above, 
the  colour  rendering  shall  be  evaluated  as  mentioned 
in  the  following  table: 

Colour  Rendering  Ra  (General  Colour 

Evaluated  Rendering  Index) 

True  90-100 

Good  70  -  90 

Moderate  50-70 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


13 


Table  4  Recommended  Values  or  Illuminance 

(Clauses  4.1.3.1, 4.1.4, 4.1.4.2, 4.3.2  and  4.3.2.1) 


SI  No. 

Type  of  Interior  or  Activity 

Range  of 

Quality  Class 

Remarks 

Service 

of  Direct 

Illuminance 

Glare 

( See  Note) 

Limitation 

lux 

( See  Note) 

(1) 

(2) 

(3) 

(4) 

(5) 

1 

AGRICULTURE  AND 
HORTICULTURE 

1.1 

Inspection  of  Farm  Produce  where 
Colour  is  Important 

300-500-750 

1 

Local  lighting  may  be  appropriate 

Other  Important  Tasks 

200-300-500 

2 

Local  lighting  may  be  appropriate 

Id 

Farm  Workshops 

1.2.1 

General 

50-100-150 

3 

1.23. 

Workbench  or  machine 

200-300-500 

2 

Local  or  portable  lighting  may  be  appropriate 

13 

Milk  Premises 

50-100-150 

3 

1.4 

Sick  Animal  Pets,  Calf  Nurseries 

30-50-100 

3 

1.5 

Other  Firm  and  Horticultural  Buildings 

20-30-50 

3 

2 

COAL  MINING  (SURFACE 
BUILDINGS) 

2.1 

Coal  Preparation  Plant 

2.1.1 

Walkways,  floors  under  conveyors 

30-50-100 

3 

2.1.2 

Wagon  loading,  bunkers 

30-50-100 

3 

2.1.3 

Elevators,  chute  transfer  pits,  wash  box 

50-100-150 

3 

area 

2.1.4 

Drum  filters,  screen,  rotating  shafts 

100-150-200 

3 

2.1.5 

Picking  belts 

150-200-300 

3 

Directional  and  colour  properties  of  lighting 
may  be  important  for  easy  recognition  of  coal 
and  rock 

2d 

Lamp  Rooms 

2d.l 

Repair  section 

200-300-500 

2 

Idd 

Other  areas 

100-150-200 

3 

23 

Weight  Cabins,  Fan  Houses 

100-150-200 

3 

2.4 

Winding  Houses 

100-150-200 

3 

3 

ELECTRICITY  GENERATION, 
TRANSMISSION  AND 
DISTRIBUTION 

3.1 

General  Plant 

3.1.1 

Turbine  houses  (operating  floor) 

150-200-300 

2 

3.1.2 

Boiler  and  turbine  house  basements 

50-100-150 

3 

3.1.3 

Boiler  houses,  platforms,  areas  around 
burners 

50-100-150 

3 

3.1.4 

Switch  rooms,  meter  rooms,  oil  plant 
rooms,  HV  substations  (indoor) 

100-150-200 

2 

3.13 

Control  rooms 

200-300-500 

1 

Localized  lighting  of  control  display  and  the 
control  desks  may  be  appropriate 

3.1.6 

Relay  and  telecommunication  rooms 

200-300-500 

2 

3.1.7 

Diesel  generator  rooms,  compressor 

100-150-200 

3 

rooms 

3.1.8 

Pump  houses,  water  treatment  plant 
houses 

100-150-200 

3 

3.1.9 

Battery  rooms,  chargers,  rectifiers 

50-100-150 

3 

3.1.10 

Precipitator  chambers,  platforms,  etc 

50-100-150 

3 

3.1.11 

Cable  tunnels  and  basements, 
circulating  water  culverts  and  screen 
chambers,  storage  tanks  (indoor), 
operating  areas  and  filling  points  at 
outdoor  tanks 

30-50-100 

3 

3d 

Coal  Plant 

3d.l 

Conveyors,  gantries,  junction  towers, 
unloading  hoppers,  ash  handling  plants, 
settling  pits,  dust  hoppers  outlets 

50-100-150 

3 

3.2 d 

Other  areas  where  operators  may  be  in 
attendance 

100-150-200 

3 

14 

NATIONAL  BUILDING  CODE  OF  INDIA  2016 

Table  4  —  ( Continued ) 


(1) 

(2) 

(3) 

(4) 

(5) 

3.3 

Nuclear  Plants 

Gas  Circulation  Bays,  Reactor  Area, 
Boiler  Platform,  Reactor  Charges  and 
Discharge  Face 

100-150-200 

2 

4 

METAL  MANUFACTURE 

4.1 

Iron  Making 

4.1.1 

Sinter  plant: 

Plant  floor 

150-200-300 

3 

Mixer  drum,  fan  house,  screen  houses, 
coolers,  transfer  stations 

100-150-200 

3 

4.1.2 

Furnaces,  cupola: 

General 

100-150-200 

3 

Control  platforms 

200-300-500 

2 

Local  lighting  may  be  appropriate 

Conveyor  galleries,  walkways 

30-50-100 

3 

4.2 

Steel  Making 

4.2.1 

Electric  melting  shops 

150-200-300 

3 

4.2.2 

Basic  oxygen  steel  making  plants 

4.2.2.1 

General 

100-150-200 

3 

4. 2. 2. 2 

Convertor  floor,  teeming  bay 

150-200-300 

3 

4. 2. 2. 3 

Control  platforms 

200-300-500 

2 

Local  lighting  may  be  appropriate 

4.2.2.4 

Scrap  bays 

100-150-200 

3 

4.3 

Metal  Forming  and  Treatment 

4.3.1 

Ingot  stripping,  soaking  pits,  annealing 
and  heat  treatment  bays,  acid  recovery 
plant  Picking  and  cleaning  bays, 
roughing  mills,  cold  mills,  finishing 
mills,  tinning  and  galvanizing  lines,  cut 
up  and  rewind  lines 

150-200-300 

3 

4.3.2 

General 

100-150-200 

3 

4.3.3 

Control  platforms 

200-300-500 

2 

Local  lighting  may  be  appropriate 

4.3.4 

Wire  mills,  product  finishing,  steel 
inspection  and  treatment 

200-300-500 

3 

4.3.5 

Plate/strip  inspection 

300-500-700 

2 

4.3.6 

Inspection  of  tin  plate,  stainless  steel, 

- 

- 

Special  lighting  to  reveal  faults  in  the  specular 

etc 

surface  of  the  material  will  be  required 

4.4 

Foundries 

4.4.1 

Automatic  plant 

4.4. 1.1 

Without  manual  operation 

30-50-100 

3 

4.4. 1.2 

With  occasional  manual  operation 

100-150-200 

3 

4.4. 1.3 

With  continuous  manual  operation 

150-200-300 

3 

4.4. 1.4 

Control  room 

200-300-500 

1 

Localized  lighting  of  the  control  display  and 
the  control  desks  may  be  appropriate 

4.4. 1.5 

Control  platforms 

200-300-500 

2 

4.4.2 

Non-automatic  plants 

4.4.2.1 

Charging  floor,  pouring,  shaking  out, 
cleaning,  grinding  fettling 

200-300-500 

3 

4.4. 2. 2 

Rough  moulding,  rough  core  making 

200-300-500 

3 

4.4.2.3 

Fine  moulding,  fine  core  making 

300-500-750 

2 

4.4.2.4 

Inspection 

300-500-750 

2 

4.5 

Forges  (Severe  vibration  is  likely  to 
occur) 

4.5.1 

General 

200-300-500 

2 

4.5.2 

Inspection 

300-500-750 

2 

5 

CERAMICS 

5.1 

Concrete  Products 

Mixing,  Casting,  Cleaning 

150-200-300 

3 

5.2 

Potteries 

5.2.1 

Grinding,  moulding,  pressing,  cleaning, 
trimming,  glazing,  firing 

200-300-500 

3 

5.2.2 

Enamelling,  colouring 

500-750-1  000 

1 

5.3 

Glass  Works 

5.3.1 

Furnace  rooms,  bending,  annealing 

100-150-200 

3 

5.3.2 

Mixing  rooms,  forming,  cutting, 
grinding,  polishing,  toughening 

200-300-500 

3 

5.3.3 

Beveling,  decorative  cutting,  etching, 
silvering 

300-500-750 

2 

5.3.4 

Inspection 

300-500-750 

2 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


15 


Table  4  —  ( Continued) 

U) 

(2) 

(3) 

(4) 

(5) 

6 

CHEMICALS 

6.1 

Petroleum,  Chemical  and  Petrochemical 
Works 

6.1.1 

Exterior  walkways,  platforms,  stairs 
and  ladders 

30-50-100 

3 

6.1.2 

Exterior  pump  and  valve  areas 

50-100-150 

3 

6.1.3 

Pump  and  compressor  houses 

100-150-200 

3 

6.1.4 

Process  plant  with  remote  control 

30-50-100 

3 

6.1.5 

Process  plant  requiring  occasional 
manual  intervention 

50-100-150 

3 

6.1.6 

Permanently  occupied  work  stations  in 
process  plant 

150-200-300 

3 

6.1.7 

Control  rooms  for  process  plant 

200-300-500 

1 

6.2 

Pharmaceutical  Manufacturer  and  Fine 
Chemicals  Manufacturer 

6.2.1 

Pharmaceutical  manufacturer  grinding, 
granulating,  mixing,  drying,  tableting, 
sterilizing,  washing,  preparation  of 
solutions,  filling,  capping,  wrapping, 
hardening 

300-500-750 

2 

6.2.2 

Fine  chemical  manufacture 

6.2.2.1 

Exterior  walkways,  platforms,  stairs  and 
ladders 

30-50-100 

3 

6. 2. 2. 2 

Process  plant 

50-100-150 

3 

6.2.2.3 

Fine  chemical  finishing 

300-500-750 

2 

6.2. 2.4 

Inspection 

300-500-750 

1 

Local  lighting  may  be  appropriate 

6.3 

Soap  Manufacture 

6.3.1 

General  area 

200-300-500 

2 

6.3.2 

Automatic  processes 

100-200-300 

2 

6.3.3 

Control  panels 

200-300-500 

1 

Local  lighting  may  be  appropriate 

6.3.4 

Machines 

200-300-500 

2 

6.4 

Paint  Works 

6.4.1 

General 

200-300-500 

2 

6.4.2 

Automatic  processes 

150-200-300 

2 

6.4.3 

Control  panels 

200-300-500 

2 

6.4.4 

Special  batch  mixing 

500-750-1  000 

2 

6.4.5 

Colour  matching 

750-1  000-1  500 

1 

7 

MECHANICAL  ENGINEERING 

7.1 

Structural  Steel  Fabrication 

7.1.1 

General 

200-300-500 

3 

7.1.2 

Marking  off 

300-500-750 

3 

Local  lighting  may  be  appropriate 

7.2 

Sheet  Metal  Works 

7.2.1 

Pressing,  punching,  shearing,  stamping, 
spinning,  folding 

300-500-750 

2 

7.2.2 

Benchwork,  scribing,  inspection 

500-750-1  000 

2 

7.3 

Machine  and  Tool  Shops 

7.3.1 

Rough  bench  and  machine  work 

200-300-500 

3 

7.3.2 

Medium  bench  and  machine  work 

300-500-750 

2 

7.3.3 

Fine  bench  and  machine  work 

500-750-1  000 

2 

7.3.4 

Gauge  rooms 

750-1000-1  500 

1 

Optical  aids  may  be  required 

7.4 

Die  Sinking  Shops 

7.4.1 

General 

300-500-750 

2 

7.4.2 

Fine  work 

1  000-1  500-2  000 

1 

Flexible  local  lighting  is  desirable 

7.5 

Welding  and  Soldering  Shops 

7.5.1 

Gas  and  arc  welding,  rough  spot 
welding 

200-300-500 

3 

7.5.2 

Medium  soldering,  brazing,  spot  welding 

300-500-750 

3 

7.5.3 

Fine  soldering,  fine  spot  welding 

750-1  000-1  500 

2 

Local  lighting  is  desirable 

7.6 

Assembly  Shops 

7.6.1 

Rough  work  for  example,  frame  and 

200-300-500 

3 

The  lighting  of  vertical  surface  may  be 

heavy  machine  assembly 

important 

7.6.2 

Medium  work,  for  example,  engine 
assembly,  vehicle  body  assembly 

300-500-750 

2 

7.6.3 

Fine  work,  for  example,  office 
machinery  assembly 

500-750-1  000 

1 

Localized  lighting  may  be  useful 

7.6.4 

Very  fine  work,  for  example, 
instrument  assembly 

750-1  000-1  500 

1 

Local  lighting  and  optical  aids  are  desirable 

7.6.5 

Minute  work,  for  example,  watch  making 

1  000-1  500-2  000 

1 

Local  lighting  and  optical  aids  are  desirable 

16 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  4  —  ( Continued ) 


(1) 

(2) 

(3) 

(4) 

(5) 

7.7 

Inspection  and  Testing  Shops 

7.7.1 

Coarse  work,  for  example,  using  go/no 
go  gauges,  inspection  of  large  sub- 
assemblies 

300-500-750 

2 

Local  or  localized  lighting  may  be  appropriate 

7.7.2 

Medium  work,  for  example,  inspection 
of  painted  surfaces 

500-750-1  000 

1 

Local  or  localized  lighting  may  be  appropriate 

7.7.3 

Fine  work,  for  example,  using 
calibrated  scales,  inspection  of 
precision  mechanisms 

750-1  000-1  500 

1 

Local  or  localized  lighting  may  be  appropriate 

7.7.4 

Very  fine  work,  for  example, 
inspection  of  small  intricate  parts 

1  000-1  500-2  000 

1 

Local  lighting  and  optical  aids  are  desirable 

7.7.5 

Minute  work,  for  example,  inspection 
of  very  small  instruments 

2  000 

1 

Local  lighting  and  optical  aids  are  desirable 

7.8 

Points  Shops  and  Spray  Booths 

7.8.1 

Dipping,  rough  spraying 

200-300-500 

3 

7.8.2 

Preparation,  ordinary  painting, 

spraying  and  finishing 

200-500-750 

2 

7.8.3 

Fine  painting,  spraying  and  finishing 

500-750-1  000 

2 

7.8.4 

Inspection,  retouching  and  matching 

750-1  000-1  500 

2 

7.9 

Plating  Shops 

7.9.1 

Vats  and  baths 

200-300-500 

3 

7.9.2 

Buffing,  polishing  burnishing 

300-500-750 

2 

7.9.3 

Final  buffing  and  polishing 

500-750-1  000 

2 

7.9.4 

Inspection 

- 

- 

Special  light  to  reveal  fault  in  the  surface  of 
the  material  will  be  required 

8 

ELECTRICAL  AND  ELECTRONIC 
ENGINEERING 

8.1 

Electrical  Equipment  Manufacture 

8.1.1 

Manufacture  of  cables  and  insulated 

200-300-500 

3 

wires,  winding,  varnishing  and 
immersion  of  coils,  assembly  of  large 
machines,  simple  assembly  work 

8.1.2 

Medium  assembly,  for  example, 
telephones,  small  motors 

300-500-750 

3 

Local  lighting  may  be  appropriate 

8.1.3 

Assembly  of  precision  components,  for 

750-1  000-1  500 

1 

Local  lighting  is  desirable.  Optical  aids  may 

example,  telecommunication 

equipment,  adjustment,  inspection  and 
calibration 

be  useful 

8.1.4 

Assembly  of  high  precision  parts 

1  000-1  500-2  000 

1 

Local  lighting  is  desirable.  Optical  aids  may 
be  useful 

8.2 

Electronic  Equipment  Manufacture 

8.2.1 

Printed  circuit  board 

8.2. 1.1 

Silk  screening 

300-500-750 

1 

Local  lighting  may  be  appropriate 

8.2. 1.2 

Hand  insertion  of  components, 
soldering 

500-750-1  000 

1 

Local  lighting  may  be  appropriate 

8.2. 1.3 

Inspection 

750-1  000-1  500 

1 

A  large,  low  luminance  luminaire  overhead 
ensures  specular  reflection  conditions  which 
are  helpful  for  inspection  of  printed  circuits 

8.2. 1.4 

Assembly  of  wiring  harness,  cleating 
harness,  testing  and  calibration 

500-750-1  000 

1 

Local  lighting  may  be  appropriated. 

8.2. 1.5 

Chassis  assembly 

750-1  000-1  500 

1 

Local  lighting  may  be  appropriated. 

8.2.2 

Inspection  and  testing 

8.2. 2.1 

Soak  test 

150-200-300 

2 

8.2.2.2 

Safety  and  functional  tests 

200-300-500 

2 

9 

FOOD,  DRINK  AND  TOBACCO 

9.1 

Slaughter  Houses 

9.1.1 

General 

200-300-500 

3 

9.1.2 

Inspection 

300-500-750 

2 

9.2 

Canning,  Preserving  and  Freezing 

9.2.1 

Grading  and  sorting  of  raw  materials 

500-750-1  000 

2 

Lamp  of  colour  rendering  group  1A  or  IB 
will  be  required,  if  colour  judgement  is 
required 

9.2.2 

Preparation 

300-500-750 

3 

9.2.3 

Canned  and  bottled  goods 

9.2.3.1 

Retorts 

200-300-500 

3 

9.2.3.2 

Automatic  processes 

150-200-300 

3 

9.2.3.3 

Labelling  and  packaging 

200-300-500 

3 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


17 


Table  4  —  ( Continued) 

(1) 

(2) 

(3) 

(4) 

(5) 

9.2.4 

Frozen  foods 

9.2.4.1 

Process  area 

200-300-500 

3 

9.2.4.2 

Packaging  and  storage 

200-300-500 

3 

9.3 

Bottling,  Brewing  and  Distilling 

9.3.1 

Keg  washing  and  handling,  bottle 
washing 

150-200-300 

3 

9.3.2 

Keg  inspection 

200-300-500 

3 

9.3.3 

Bottle  inspection 

Special  lighting  will  be  required 

9.3.4 

Process  areas 

200-300-500 

3 

9.3.5 

Bottle  filling 

500-750-1  000 

3 

9.4 

Edible  Oils  and  Fats  Processing 

9.4.1 

Refining  and  blending 

200-300-500 

3 

9.4.2 

Production 

300-500-750 

2 

9.5 

Mills-Milling,  Filtering  and  Packing 

200-300-500 

3 

9.6 

Bakeries 

9.6.1 

General 

200-300-500 

2 

9.6.2 

Hand  decorating,  icing 

300-500-750 

2 

9.7 

Chocolate  and  Confectionery 

Manufacture 

9.7.1 

General 

200-300-500 

3 

9.7.2 

Automatic  processes 

150-200-300 

3 

9.7.3 

Hand  decoration,  inspection,  wrapping 

300-500-750 

2 

If  accurate  colour  judgements  are  required, 

and  packing 

lamps  of  colour  rendering  group  1A  or  IB  are 
used 

9.8 

Tobacco  Processing 

9.8.1 

Material  preparation,  making  and 
packing 

300-500-750 

2 

10 

TEXTILES 

10.1 

Fibre  Preparation 

10.1.1 

Bale  breaking,  washing 

200-300-500 

3 

10.1.2 

Stock  dyeing,  tinting 

200-300-500 

3 

10.2 

Yam  Manufacture 

10.2.1 

Spinning,  roving,  winding,  etc 

300-500-750 

2 

10.2.2 

Healding  (drawing  in) 

750-1000-750 

2 

10.3 

Fabric  Production 

10.3.1 

Knitting 

300-500-750 

2 

10.3.2 

Weaving 

10.3.2.1 

Jute  and  hemp 

200-300-500 

2 

10.3.2.2 

Heavy  woolens 

300-500-750 

1 

10.3.2.3 

Medium  worsteds,  fine  woolens, 
cottons 

500-750-1  000 

1 

10.3.2.4 

Fine  worsteds,  fine  linens,  synthetics 

750-1  000-1  500 

1 

10.3.2.5 

Mending 

1  000-1  500-2  000 

1 

10.3.2.6 

Inspection 

1  000-1  500-2  000 

1 

10.4 

Fabric  Finishing 

10.4.1 

Dyeing 

200-300-500 

3 

10.4.2 

Calendaring,  chemical  treatment,  etc 

300-500-750 

2 

10.4.3 

Inspection 

10.4.3.1 

'Grey’  cloth 

750-1  000-1  500 

1 

10.4.3.2 

Final 

1  000-1  500-2  000 

1 

10.5 

Carpet  Manufacture 

10.5.1 

Winding,  beaming 

200-300-500 

3 

10.5.2 

Setting  pattern,  turfing  cropping, 
trimming,  fringing,  latexing  and  latex 
drying 

300-500-750 

2 

10.5.3 

Designing,  weaving,  mending 

500-750-1  000 

2 

10.5.4 

Inspection 

10.5.4.1 

General 

750-1  000-1  500 

1 

Local  lighting  may  be  appropriate 

10.5.4.2 

Piece  dyeing 

500-750-1  000 

1 

Local  lighting  may  be  appropriate 

11 

LEATHER  INDUSTRY 

11.1 

Leather  Manufacture 

11.1.1 

Cleaning,  tanning  and  stretching,  vats, 
cutting,  fleshing,  stuffing 

200-300-500 

3 

11.1.2 

Finishing,  scarfing 

300-500-750 

2 

11.2 

Leather  Working 

11.2.1 

General 

200-300-500 

3 

11.2.2 

Pressing,  glazing 

300-500-750 

2 

18 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  4  —  ( Continued) 

U) 

(2) 

(3) 

(4) 

(5) 

11.2.3 

Cutting,  splitting,  scarfing,  sewing 

500-750-1  000 

2 

Directional  lighting  may  be  useful. 

11.2.4 

Grading,  matching 

2 

Local  lighting  may  be  appropriate 

12 

CLOTHING  AND  FOOTWEAR 

12.1 

Clothing  Manufacture 

12.1.1 

Preparation  of  cloth 

200-300-500 

2 

12.1.2 

Cutting 

500-750-1  000 

1 

12.1.3 

Matching 

500-750-1  000 

1 

12.1.4 

Sewing 

750-1  000-1  500 

1 

12.1.5 

Pressing 

300-500-750 

2 

12.1.6 

Inspection 

1  000-1  500-2  000 

1 

Local  lighting  may  be  appropriate 

12.1.7 

Hand  tailoring 

1  000-1  500-2  000 

1 

Local  lighting  may  be  appropriate 

12.2 

Hosiery  and  Knitwear  Manufacture 

12.2.1 

Flat  bed  knitting  machines 

300-500-750 

2 

12.2.2 

Circular  knitting  machines 

500-750-1000 

2 

12.2.3 

Lockstitch  and  overlocking  machine 

750-1  000-1  500 

1 

12.2.4 

Linking  or  running  on 

750-1  000-1  500 

1 

12.2.5 

Mending,  handfinishing 

1  000-1  500-3  000 

- 

Local  lighting  may  be  appropriate 

12.2.6 

Inspection 

1  000-1  500-2  000 

2 

Local  lighting  may  be  appropriate 

12.3 

Glove  Manufacture 

12.3.1 

Sorting  and  grading 

500-750-1  000 

1 

12.3.2 

Pressing,  knitting,  cutting 

300-500-750 

2 

12.3.3 

Sewing 

500-750-1  000 

2 

12.3.4 

Inspection 

1  000-1  500-2  000 

- 

Local  lighting  may  be  appropriate 

12.4 

Hat  Manufacture 

12.4.1 

Stiffening,  braiding,  refining,  forming, 
sizing,  pounding,  ironing 

200-300-500 

2 

12.4.2 

Cleaning,  flanging,  finishing 

300-500-750 

2 

12.4.3 

Sewing 

500-750-1000 

2 

12.4.4 

Inspection 

1  000-1  500-2  000 

- 

Local  lighting  may  be  appropriate 

12.5 

Boot  and  Shoe  Manufacture 

12.5.1 

Leather  and  synthetics 

12.5.2 

Sorting  and  grading 

750-1  000-1  500 

1 

12.5.3 

Clicking,  closing 

750-1  000-1  500 

2 

Local  or  localized  lighting  may  be  appropriate 

12.5.4 

Preparatory  operations 

750-1  000-1  500 

2 

Local  or  localized  lighting  may  be  appropriate 

12.5.5 

Cutting  tables  and  pressure 

1  000-1  500-2  000 

1 

Local  or  localized  lighting  may  be  appropriate 

12.5.6 

Bottom  stock  preparation,  lasting, 
bottoming  finishing,  shoe  rooms 

750-1  000-1  500 

1 

Local  or  localized  lighting  may  be  appropriate 

12.5.7 

Rubber 

12.5.7.1 

Washing,  compounding,  coating, 
drying,  varnishing,  vulcanizing, 

calendaring,  cutting 

200-300-500 

3 

12.5.7.2 

Lining,  making  and  finishing 

300-500-750 

2 

13 

TIMBER  AND  FURNITURE 

13.1 

Sawmills 

13.1.1 

General 

150-200-300 

3 

13.1.2 

Head  saw 

300-500-750 

2 

Localized  lighting  may  be  appropriate 

13.1.3 

Grading 

500-750-1  000 

2 

Directional  lighting  may  be  useful 

13.2 

Woodwork  Shops 

13.2.1 

Rough  sawing,  bench  work 

200-300-500 

2 

13.2.2 

Sizing,  planning,  sanding,  medium 
machining  and  bench  work 

300-500-750 

2 

13.2.3 

Fine  bench  and  machine  work,  fine 
sanding,  finishing 

500-750-1  000 

2 

Localized  lighting  may  be  appropriate 

13.3 

Furniture  Manufacture 

13.3.1 

Raw  material  stores 

50-100-150 

3 

13.3.2 

Finished  goods  stores 

100-150-200 

3 

13.3.3 

Wood  matching  and  assembly,  rough 
sawing,  cutting 

200-300-500 

2 

13.3.4 

Machining,  sanding  and  assembly, 
polishing 

300-500-750 

2 

Localized  lighting  may  be  appropriate 

13.3.5 

Tool  room 

300-500-750 

2 

13.3.6 

Spray  booths 

13.3.6.1 

Colour  finishing 

300-500-750 

2 

13.3.6.2 

Clear  finishing 

200-300-500 

2 

13.3.7 

Cabinet  making 

13.3.7.1 

Veneer  sorting  and  grading 

750-1  000-1  500 

1 

13.3.7.2 

Marquetry,  pressing,  patching  and  fitting 

300-500-750 

1 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


19 


Table  4  —  ( Continued) 

U) 

(2) 

(3) 

(4) 

(5) 

13.3.7.3 

Final  inspection 

500-750-1  000 

1 

Special  lighting  will  be  required 

13.4 

Upholstery  Manufacture 

13.4.1 

Cloth  inspection 

1  000-1  500-2  000 

1 

Special  lighting  will  be  required 

13.4.2 

Filling,  covering 

300-500-750 

2 

13.4.3 

Slipping,  cutting,  sewing 

500-750-1  000 

2 

13.4.4 

Mattress  making 

13.4.5 

Assembly 

300-500-750 

2 

13.4.6 

Tape  edging 

750-1  000-1  500 

2 

Local  lighting  may  be  appropriate 

14 

PAPER  AND  PRINTING 

14.1 

Paper  Mills 

14.1.1 

Pulp  mills,  preparation  plants 

200-300-500 

3 

14.1.2 

Paper  and  board  making 

14.1.2.1 

General 

200-300-500 

3 

14.1.2.2 

Automatic  process 

150-200-300 

3 

Supplementary  lighting  may  be  necessary  for 
maintenance  work 

14.1.2.3 

Inspection,  sorting 

300-500-750 

1 

14.1.3 

Paper  converting  processes 

14.1.3.1 

General 

200-300-500 

3 

14.1.3.2 

Associated  printing 

300-500-750 

2 

14.2 

Printing  Works 

14.2.1 

Type  foundries 

14.2.1.1 

Matrix  making,  dressing  type,  hand  and 
machine  coating 

200-300-500 

3 

14.2.1.2 

Front  assembly,  sorting 

500-750-1  000 

2 

14.2.2 

Composing  rooms 

14.2.2.1 

Hand  composing,  imposition  and 
distribution 

500-750-1  000 

1 

14.2.2.2 

Hot  metal  keyboard 

500-750-1  000 

1 

14.2.2.3 

Hot  metal  casting 

200-300-500 

2 

14.2.2.4 

Photo  composing  keyboard  or  setters 

300-500-750 

1 

14.2.2.5 

Paste  up 

500-750-1  000 

1 

14.2.2.6 

Illuminated  tables  -  general  lighting 

200-300-500 

Dimming  may  be  required 

14.2.2.7 

Proof  presses 

300-500-750 

2 

14.2.2.8 

Proof  reading 

500-750-1  000 

1 

14.2.3 

Graphic  Reproduction 

14.2.3.1 

General 

300-500-750 

2 

14.2.3.2 

Precision  proofing,  retouching,  etching 

750-1  000-1  500 

1 

Local  lighting  may  be  appropriate 

14.2.3.3 

Colour  reproduction  and  inspection 

750-1  000-1  500 

1 

14.2.4 

Printing  machine  room 

14.2.4.1 

Presses 

300-500-750 

2 

14.2.4.2 

Premake  ready 

300-500-750 

2 

14.2.4.3 

Printed  sheet  inspection 

750-1  000-1  500 

1 

14.2.5 

Binding 

14.2.5.1 

Folding,  pasting,  punching  and 
stitching 

300-500-750 

2 

14.2.5.2 

Cutting,  assembling,  embossing 

500-750-1  000 

2 

15 

PLASTIC  AND  RUBBER 

15.1 

Plastic  Products 

15.1.1 

Automatic  plant 

15.1.1.1 

Without  manual  control 

30-50-100 

3 

15.1.1.2 

With  occasional  manual  control 

50-100-150 

3 

15.1.1.3 

With  continuous  manual  control 

200-300-500 

3 

15.1.1.4 

Control  rooms 

200-300-500 

1 

15.1.1.5 

Control  platforms 

200-300-500 

2 

Local  lighting  may  be  appropriate 

15.1.2 

Non-automatic  plant 

15.1.2.1 

Mixing,  calendaring,  extrusion, 

injection,  compression  and  blow 
moulding,  sheet  fabrication 

200-300-500 

3 

15.1.2.2 

Trimming,  cutting,  polishing, 

cementing 

300-500-750 

2 

15.1.2.3 

Printing,  inspection 

750-1  000-1  500 

1 

15.2 

Rubber  Products 

15.2.1 

Stock  preparation  -  plasticizing, 
milling 

150-200-300 

3 

15.2.2 

Calendaring,  fabric  preparation,  stock¬ 
cutting 

300-500-750 

3 

20 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  4  —  ( Continued) 

(1) 

(2) 

(3) 

(4) 

(5) 

15.2.3 

Extruding,  moulding 

300-500-750 

2 

15.2.4 

Inspection 

750-1  000-1  500 

- 

16 

DISTRIBUTION  AND  STORAGE 

16.1 

Work  Stores 

100-150-200 

3 

Avoid  glare  to  drivers  of  vehicles  approaching 
the  loading  bay 

16.1.1 

Unpacking,  sorting 

150-200-300 

3 

Avoid  glare  to  drivers  of  vehicles  approaching 
the  loading  bay 

16.1.2 

Large  item  storage 

50-100-150 

3 

Avoid  glare  to  drivers  of  vehicles  approaching 
the  loading  bay 

16.1.3 

Small  item  rack  storage 

200-300-500 

3 

Avoid  glare  to  drivers  of  vehicles  approaching 
the  loading  bay 

16.1.4 

Issue  counter,  records,  storeman’s  desk 

300-500-750 

2 

Local  or  localized  lighting  may  be  appropriate 

16.2 

Warehouses  and  Bulk  Stores 

16.2.1 

Storage  of  goods  where  indentification 
requires  only  limited  preparation  of 
detail 

50-100-150 

3 

16.2.2 

Storage  of  goods  where  identification 
requires  perception  of  detail 

100-150-200 

3 

16.2.3 

Automatic  high  bay  rack  stores 

16.2.3.1 

Gangway 

20 

16.2.3.2 

Control  station 

150-200-300 

3 

16.2.3.3 

Packing  and  dispatch 

200-300-500 

3 

16.2.3.4 

Loading  bays 

100-150-200 

3 

Avoid  glare  to  drivers  of  vehicles  approaching 
the  loading  bay 

16.3 

Cold  Stores 

16.3.1 

General 

200-300-500 

3 

16.3.2 

Breakdown,  make-up  and  dispatch 

200-300-500 

3 

16.3.3 

Loading  bays 

100-150-200 

3 

Avoid  glare  to  drivers  of  vehicles  approaching 
the  loading  bay 

17 

COMMERCE 

17.1 

Offices 

17.1.1 

General  offices 

300-500-750 

1 

17.1.2 

Deep  plan  general  offices 

500-750-1000 

1 

17.1.3 

Computer  work  stations 

300-500-750 

1 

17.1.4 

Conference  rooms,  executive  offices 

300-500-750 

1 

17.1.5 

Computer  and  data  preparation  rooms 

300-500-750 

1 

171.6 

Filing  rooms 

200-300-500 

1 

17.2 

Drawing  Offices 

17.2.1 

General 

300-500-750 

1 

17.2.2 

Drawing  boards 

500-750-1  000 

1 

17.2.3 

Computer  aided  design  and  drafting 

Special  lighting  is  required 

17.2.4 

Print  rooms 

200-300-500 

1 

17.3 

Banks  and  Building  Societies 

17.3.1 

Counter,  office  area 

300-500-750 

1 

17.3.2 

Public  area 

200-300-500 

1 

18 

SERVICES 

18.1 

Garages 

18.1.1 

Interior  parking  areas 

20-30-50 

3 

18.1.2 

General  repairs,  servicing,  washing, 
polishing 

200-300-500 

2 

18.1.3 

Workbench 

300-500-750 

1 

Local  or  localized  lighting  may  be  appropriate 

18.1.4 

Spray  booths 

300-500-750 

1 

18.1.5 

External  apron 

18.1.5.1 

General 

30-50-100 

Care  should  be  taken  to  avoid  glare  to  drivers 
and  neighbouring  residents 

18.1.5.2 

Pump  area  (retail  sales) 

200-300-500 

See  'Retailing’ 

18.2 

Appliance  servicing 

18.2.1 

Workshop 

18.2.1.1 

General 

200-300-500 

2 

18.2.1.2 

Workbench 

300-500-750 

2 

Localized  lighting  may  be  appropriate 

18.2.1.3 

Counter 

200-300-500 

2 

Localized  lighting  may  be  appropriate 

18.2.1.4 

Stores 

200-300-500 

3 

18.3 

Laundries 

18.3.1 

Commercial  laundries 

18.3.2 

Receiving,  sorting,  washing,  drying, 

200-300-500 

3 

ironing,  despatch,  dry-cleaning,  bulk 
machine  work 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


21 


Table  4  —  ( Continued ) 

0) (2) (3) (4) 


18.3.3 

Head  ironing,  pressing,  mending, 
spotting,  inspection 

300-500-750 

18.3.4 

Launderettes 

200-300-500 

18.4 

Sewage  Treatment  Works 

18.4.1 

Walkways 

30-50-100 

18.4.2 

Process  areas 

50-100-150 

19 

RETAILING 

19.1 

Small  Shops  with  Counters 

300-500-750 

19.2 

Small  Self-Service  Shops  with  Island 
Displays 

300-500-750 

19.3 

Super  Markets,  Hyper-Markets 

19.3.1 

General 

300-500-750 

19.3.2 

Checkout 

300-500-750 

19.3.3 

Showroom  for  large  objects,  for 
example,  cars,  furniture 

300-500-750 

19.3.4 

Shopping  precincts  and  arcades 

100-150-200 

20 

PLACES  OF  PUBLIC  ASSEMBLY 

20.1 

Public  Rooms,  Village  Halls,  Worship 
Halls 

200-300-500 

20.2 

Concert  Halls,  Cinemas  and  Theatres 

20.2.1 

Foyer 

150-200-300 

20.2.2 

Booking  office 

200-300-500 

20.2.3 

Auditorium 

50-100-150 

20.2.4 

Dressing  rooms 

200-300-500 

20.2.5 

Projection  room 

100-150-200 

20.3 

Churches 

20.3.1 

Body  of  church 

100-150-200 

20.3.2 

Pulpit,  lectern 

200-300-500 

20.3.3 

Choir  stalls 

200-300-500 

20.3.4 

Alter,  communion  table,  chancel 

100-150-200 

20.3.5 

Vestries 

100-150-200 

20.3.6 

Organ 

200-300-500 

20.4 

Hospitals 

20.4.1 

Anaesthetic  rooms 

20.4.1.1 

General 

200-300-500 

20.4.1.2 

Local 

750-1  000-1  500 

20.4.2 

Consulting  areas 

20.4.2.1 

General 

200-300-500 

20.4.2.2 

Examination 

750-1  000-1  500 

20.4.3 

Corridors 

20.4.3.1 

General 

100-150-200 

20.4.4 

Ward  corridors 

20.4.4.1 

Day,  screened  from  bays 

150-200-300 

20.4.4.2 

Day,  open  to  natural  light 

150-200-300 

(total) 

20.4.4.3 

Morning/ evening 

100-150-200 

20.4.4.4 

Night 

5-10 

20.4.5 

Cubicles 

20.4.5.1 

General 

200-300-500 

20.4.5.2 

Treatment 

750-1  000-1  500 

20.4.6 

Examination 

20.4.6.1 

General 

200-300-500 

20.4.6.2 

Local  inspection 

750-1  000-1  500 

20.4.7 

Intensive  therapy 

20.4.7.1 

Bad  head 

30-50 

20.4.7.2 

Circulation  between  bed  ends 

50-100-150 

20.4.7.3 

Observation 

200-300-500 

20.4.7.4 

Local  observation 

750-1  000-1  500 

20.4.7.5 

Staff  base  (day) 

200-300-500 

20.4.7.6 

Staff  base  (night) 

30 

20.4.8 

Laboratories 

20.4.8.1 

General 

200-300-500 

20.4.8.2 

Examination 

300-500-750 

20.4.9 

Nurses’  stations 

22 

(5) 


The  service  illuminance  should  be  provided 
on  the  horizontal  plane  of  the  counter.  Where 
wall  displays  are  used,  a  similar  illuminance 
on  the  walls  is  desirable 


Local  or  localized  lighting  may  be  appropriate 
Dimming  facilities  will  be  necessary.  Special 
lighting  of  the  aisles  is  desirable 
Special  mirror  lighting  for  make-up  may  be 
required 


Use  local  lighting 
Local  lighting  may  be  appropriate 
Additional  lighting  to  provide  emphasis  is 
desirable 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  4  —  ( Continued ) 


(5) 


(1) 

(2) 

(3) 

20.4.9.1 

Morning/day/evening 

200-300-500 

20.4.9.2 

Night  desks 

30 

20.4.9.3 

Night,  medical  trolleys 

50-100-150 

20.4.10 

Operating  theatres 

20.4.10.1 

General 

300-500-750 

20.4.10.2 

Local 

10  000  to  50  000 

20.4.11 

Pathology  departments 

20.4.11.1 

General 

200-300-500 

20.4.11.2 

Examination 

300-500-750 

20.4.11.3 

Pharmacies 

200-300-500 

20.4.11.4 

Reception/enquiry 

200-300-500 

20.4.11.5 

Recovery  rooms 

200-300-500 

20.4.12 

Ward-circulation 

20.4.12.1 

Day 

50-100-150 

20.4.12.2 

Morning/evening 

50-100-150 

20.4.12.3 

Night 

3-5 

20.4.13 

Ward-bed  head 

20.4.13.1 

Morning/evening 

30-50 

20.4.13.2 

Reading 

100-150-200 

20.4.14 

Night 

20.4.14.1 

Adult 

0.1-1 

20.4.14.2 

Pediatric 

1 

20.4.14.3 

Psychiatric 

1-5 

20.4.14.4 

Watch 

5 

20.4.15 

X-Ray  areas 

20.4.15.1 

General 

150-200-300 

20.4.15.2 

Diagnostic 

150-200-300 

20.4.15.3 

Operative 

200-300-500 

20.4.15.4 

Process  dark  room 

50 

20.4.16 

Surgeries 

20.4.16.1 

General 

200-300-500 

20.4.16.2 

Waiting  rooms 

100-150-200 

20.4.17 

Dental  surgeries 

20.4.17.1 

Chair 

Special  lighting 

20.4.17.2 

Laboratories 

300-500-750 

20.4.18 

Consulting  rooms 

20.4.18.1 

General 

200-300-500 

20.4.18.2 

Desk 

300-500-750 

20.4.18.3 

Examination  couch 

300-500-750 

20.4.18.4 

Ophthalmic  wall  and  near-vision  charts 

300-500-750 

20.5 

Hotels 

20.5.1 

Entrance  halls 

50-100-150 

20.5.2 

Reception,  cashier’s  and  porters’  desks 

200-300-500 

20.5.3 

Bars,  coffee  base,  dining  rooms,  grill 
rooms,  restaurants,  lounges 

50-200 

20.5.4 

Cloak  rooms,  baggage  rooms 

50-100-150 

20.5.5 

Bed  rooms 

30-50-100 

20.5.6 

Bathroom 

50-100-150 

20.5.7 

Food  preparation  and  stores,  cellars, 
lifts  and  corridors 

20.6 

Libraries 

20.6.1 

Lending  library 

20.6.1.1 

General 

200-300-500 

20.6.1.2 

Counters 

300-500-750 

20.6.1.3 

Bookshelves 

100-150-200 

20.6.1.4 

Reading  rooms 

200-300-500 

20.6.1.5 

Reading  tables 

200-300-500 

20.6.2 

Catalogues 

20.6.2.1 

Card 

100-150-200 

20.6.2.2 

Microfiche/Visual  display  units 

100-150-200 

20.6.3 

Reference  libraries 

20.6.3.1 

General 

200-300-500 

20.6.3.2 

Counters 

300-500-750 

Special  operating  lights  are  used. 


Localized  lighting  may  be  appropriate. 

The  lighting  should  be  designed  to  create  an 
appropriate  atmosphere 

Supplementary  local  lighting  at  the  bed  head, 
writing  table  should  be  provided 
Supplementary  local  lighting  near  the  mirror 
is  desirable 

See  'General  Building  Areas’ 


Localized  lighting  may  be  appropriate. 

The  service  illuminance  should  be  provided 
on  the  vertical  face  at  the  bottom  of  the 
bookstack 

Localized  lighting  may  be  appropriate 


Localized  lighting  may  be  appropriate. 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


23 


Table  4  —  ( Continued ) 


(1) 

(2) 

(3) 

(4) 

(5) 

20.6.3.3 

Bookshelves 

100-150-200 

2 

The  service  illuminance  should  be  provided 
on  a  vertical  surface  at  the  foot  of  the 
bookshelves 

20.6.3.4 

Study  tables,  carrels 

300-500-750 

1 

20.6.3.5 

Map  room 

200-300-500 

1 

20.6.4 

Display  and  exhibition  areas 

20.6.4.1 

Exhibits  insensitive  to  light 

200-300-500 

20.6.4.2 

Exhibit  sensitive  to  light,  for  example, 
pictures,  prints,  rare  books  in  archives 

50  to  150 

20.6.5 

Library  workrooms 

20.6.5.1 

Book  repair  and  binding 

300-500-750 

2 

20.6.5.2 

Catalogue  and  sorting 

300-500-750 

2 

20.6.5.3 

Remote  book  stores 

100-150-200 

3 

20.7 

Museums  and  Art  Galleries 

20.7.1 

Exhibits  insensitive  to  light 

200-300-500 

20.7.2 

Light  sensitive  exhibits,  for  example, 

150 

This  is  a  maximum  illuminance  to  be 

oil  and  temper  paints,  undyed  leather, 
bone,  ivory,  wood,  etc 

provided  on  the  principal  plane  of  the  exhibit 

20.7.3 

Extremely  light  sensitive  exhibits,  for 

50 

This  is  the  maximum  illuminance  to  be 

example,  textiles,  water  colours,  prints 
and  drawings,  skins,  botanical 
specimens,  etc 

provided  on  the  principal  plane  of  the  object 

20.7.4 

Conservation  studies  and  workshops 

300-500-750 

1 

20.8 

Sports  Facilities 

Multi-purpose  sports  halls 

300-750 

This  lighting  system  should  be  sufficiently 
flexible  to  provide  lighting  suitable  for  the 
variety  of  sports  and  activities  that  take  place 
in  sports  halls.  Higher  illuminance  of  1000- 
2000  lux  would  be  required  for  television 

coverage 

21 

EDUCATION 

21.1 

Assembly  Halls 

21.1.1 

General 

200-300-500 

3 

21.1.2 

Platform  and  stage 

Special  lighting  to  provide  emphasis  and  to 
facilitate  the  use  of  the  platform/  stage  is 
desirable 

21.2 

Teaching  Spaces 

General 

200-300-500 

1 

21.3 

Lecture  Theatres 

21.3.1 

General 

200-300-500 

1 

21.3.2 

Demonstration  benches 

300-500-750 

1 

Localized  lighting  may  be  appropriate 

21.4 

Seminar  Rooms 

300-500-750 

1 

21.5 

Art  Rooms 

300-500-750 

1 

21.6 

Needlework  Rooms 

300-500-750 

1 

21.7 

Laboratories 

300-500-750 

1 

21.8 

Libraries 

200-300-500 

1 

21.9 

Music  Rooms 

200-300-500 

1 

21.10 

Sports  Halls 

200-300-500 

1 

21.11 

Workshops 

200-300-500 

1 

22 

TRANSPORT 

22.1 

Airports 

22.1.1 

Ticket  counters,  checking  desks,  and 
information  desks 

300-500-750 

2 

Localized  lighting  may  be  appropriate 

22.1.2 

Departure  lounges,  other  waiting  areas 

150-200-300 

2 

22.1.3 

Baggage  reclaim 

150-200-300 

2 

22.1.4 

Baggage  handling 

50-100-150 

2 

22.1.5 

Customs  and  immigration  halls 

300-500-750 

2 

22.1.6 

Concourse 

150-200-300 

2 

22.2 

Railway  Stations 

22.2.1 

Ticket  office 

300-500-750 

2 

Localized  lighting  may  be  appropriate 

22.2.2 

Information  office 

300-500-750 

2 

Localized  lighting  over  the  counter  may  be 
appropriate 

22.2.3 

Parcels  office,  left 

22.2.4 

Luggage  office 

22.2.4.1 

General 

50-100-150 

2 

22.2.4.2 

Counter 

150-200-300 

2 

22.2.5 

Waiting  rooms 

150-200-300 

2 

22.2.6 

Concourse 

150-200-300 

2 

24 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  4  —  ( Concluded ) 


(1) 

(2) 

(3) 

(4) 

(5) 

22.2.7 

Time  table 

150-200-300 

2 

Localized  lighting  may  be  appropriate 

2Z2.8 

Ticket  barriers 

150-200-300 

2 

Localized  lighting  may  be  appropriate 

22.2.9 

Platforms  (covered) 

30-50-100 

2 

Care  should  be  taken  to  light  and  mark  the 
edge  of  the  platform  clearly 

22J.10 

Platforms  (open) 

20 

Care  should  be  taken  to  light  and  mark  the 
edge  of  the  platform  clearly 

22.3 

Coach  Stations 

22.3.1 

Ticket  offices 

300-500-750 

2 

Localized  lighting  over  the  counter  may  be 
appropriate 

223.2 

Information  offices 

300-500-750 

2 

Localized  lighting  over  the  counter  may  be 
appropriate 

2233 

Left  luggage  office 

2233.1 

General 

50-100-150 

3 

2233.2 

Counter 

150-200-300 

3 

Localized  lighting  is  appropriate 

223.4 

Waiting  rooms 

150-200-300 

2 

223.5 

Concourse 

150-200-300 

2 

223.6 

Time  tables 

150-200-300 

2 

Local  lighting  is  appropriate 

223.7 

Loading  areas 

100-150-200 

3 

23 

GENERAL  BUILDING  AREAS 

23.1 

Entrance 

23.1.1 

Entrance  halls,  lobbies,  waiting  rooms 

150-200-300 

2 

23.13 

Enquiry  desks 

300-500-750 

2 

Localized  lighting  may  be  appropriate 

23.13 

Gatehouses 

150-200-300 

2 

23.2 

Circulation  Areas 

23.2.1 

Lifts 

50-100-150 

23.23 

Corridors,  passageways,  stairs 

50-100-150 

2 

233.3 

Escalators,  revelators 

100-150-200 

233 

Medical  and  First  Aid  Centres 

233.1 

Consulting  rooms,  treatment  rooms 

300-500-750 

1 

2333 

Rest  rooms 

100-150-200 

1 

2333 

Medical  stores 

100-150-200 

2 

23.4 

Staff  Rooms 

23.4.1 

Changing,  locker  and  cleaners  rooms, 
cloakrooms,  lavatories 

50-100-150 

23.43 

Rest  rooms 

100-150-200 

1 

233 

Staff  Restaurants 

233.1 

Canteens,  cafeterias,  dining  rooms. 

150-200-300 

2 

mess  rooms 

2333 

Servery,  vegetable  preparation, 

washing-up  area 

200-300-500 

2 

2333 

Food  preparation  and  cooking 

300-500-750 

2 

233.4 

Food  stores,  cellars 

100-150-200 

2 

23.6 

Communications 

23.6.1 

Switchboard  rooms 

200-300-500 

2 

23.63 

Telephone  apparatus  rooms 

100-150-200 

2 

23.63 

Telex  room,  post  room 

300-500-750 

2 

23.6.4 

Reprographic  room 

200-300-500 

2 

23.7 

Building  Services 

23.7.1 

Boiler  houses 

23.7.1.1 

General 

50-100-150 

3 

23.7.13 

Boiler  front 

100-150-200 

3 

23.7.13 

Boiler  control  room 

200-300-500 

2 

Localized  lighting  of  the  control  display  and 
the  control  desk  may  be  appropriate 

23.7.1.4 

Control  rooms 

200-300-500 

2 

Localized  lighting  of  the  control  display  and 
the  control  desk  may  be  appropriate 

23.7.13 

Mechanical  plant  room 

100-150-200 

2 

23.7.1.6 

Electrical  power  supply  and 
distribution  rooms 

100-150-200 

2 

23.7.1.7 

Store  rooms 

50-100-150 

3 

23.8 

Car  Parks 

23.8.1 

Covered  car  parks 

23.8.1.1 

Floors 

5-20 

233.1.2 

Ramps  and  comers 

30 

23.8.13 

Entrances  and  exits 

50-100-150 

23.8.1.4 

Control  booths 

150-200-300 

23.8.13 

Outdoor  car  parks 

5-20 

NOTE 

—  For  details  on  use  of  the  ranges  of  illumination  given  in 

three  steps  in 

this  table,  reference  shall  be  made  to  4. 1.4.2, 

4.1.43.1  and  4.1.433.  For  details  on  quality  class  of  direct  glare  limitation,  reference  shall  be  made  to  4.13.1. 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


25 


4.1.7  For  detailed  information  regarding  principles  of 
good  lighting,  reference  may  be  made  to  good  practice 
[8-1(2)]. 

4.2  Daylighting 

The  primary  source  of  lighting  for  daylighting  is  the 
sun.  The  light  received  by  the  earth  from  the  sun  consists 
of  two  parts,  namely,  direct  solar  illuminance  and  sky 
illuminance.  For  the  purposes  of  daylighting  design, 
direct  solar  illuminance  shall  not  be  considered  and 
only  sky  illuminance  shall  be  taken  as  contributing  to 
illumination  of  the  building  interiors  during  the  day. 

4.2.1  The  relative  amount  of  sky  illuminance  depends 
on  the  position  of  the  sun  defined  by  its  altitude,  which 
in  turn,  varies  with  the  latitude  of  the  locality,  the  day 
of  the  year  and  the  time  of  the  day,  as  indicated  in 
Table  5. 

4.2.2  The  external  available  horizontal  sky  illuminance 
(diffuse  illuminance)  values  which  are  exceeded  for 
about  90  percent  of  the  daytime  working  hours  may  be 
taken  as  outdoor  design  illuminance  values  for  ensuring 
adequacy  of  daylighting  design.  The  outdoor  design 
sky  illuminance  varies  for  different  climatic  regions  of 
the  country.  The  recommended  design  sky  illuminance 
values  are  6  800  lux  for  cold  climate,  8  000  lux  for 
composite  climate,  9  000  lux  for  warm  humid  climate, 
9  000  lux  for  temperate  climate  and  1 0  500  lux  for  hot- 
dry  climate.  For  integration  with  the  artificial  lighting 
during  daytime  working  hours  an  increase  of  500  lux 
in  the  recommended  sky  design  illuminance  for 
daylighting  is  suggested. 

4.2.3  The  daylight  factor  is  dependent  on  the  sky 
luminance  distribution,  which  varies  with  atmospheric 
conditions.  A  clear  design  sky  with  its  non-uniform 
distribution  of  luminance  is  adopted  for  the  purposes 
of  design  in  this  Section. 

4.2.4  Components  of  Daylight  Factor 

Daylight  factor  is  the  sum  of  all  the  daylight  reaching 
on  an  indoor  reference  point  from  the  following  sources: 

a)  Direct  sky  visible  from  the  point, 

b)  External  surfaces  reflecting  light  directly  to 
the  point  ( see  Note  1),  and 

c)  Internal  surfaces  reflecting  and  inter-reflecting 
light  to  the  point. 

NOTES 

1  External  surface  reflection  may  be  computed  approximately 
only  for  points  at  the  centre  of  the  room,  and  for  detailed  analysis 
procedures  are  complicated  and  these  may  be  ignored  for  actual 
calculations. 

2  Each  of  the  three  components,  when  expressed  as  a  ratio  or 
percent  of  the  simultaneous  external  illuminance  on  the 


horizontal  plane,  defines  respectively  the  sky  component  (SC), 
the  external  reflected  component  (ERC)  and  the  internal 
reflected  component  (IRC)  of  the  daylight  factor. 

4.2.4. 1  The  daylight  factors  on  the  horizontal  plane  only 
are  usually  taken,  as  the  working  plane  in  a  room  is 
generally  horizontal;  however,  the  factors  in  vertical 
planes  should  also  be  considered  when  specifying 
daylighting  values  for  special  cases,  such  as  daylighting 
on  classrooms,  blackboards,  pictures  and  paintings  hung 
on  walls. 

4.2.5  Sky  Component  (SC) 

Sky  component  for  a  window  of  any  size  is  computed 
by  the  use  of  the  appropriate  table  of  Annex  B. 

a)  The  recommended  sky  component  level 
should  be  ensured  generally  on  the  working 
plane  at  the  following  positions: 

1)  At  a  distance  of  3  m  to  3.75  m  from  the 
window  along  the  central  line 
perpendicular  to  the  window, 

2)  At  the  centre  of  the  room  if  more 
appropriate,  and 

3)  At  fixed  locations,  such  as  school  desks, 
blackboards  and  office  tables. 

b)  The  daylight  area  of  the  prescribed  sky 
component  should  not  normally  be  less  than 
half  the  total  area  of  the  room. 

4.2.5. 1  The  values  obtainable  from  the  tables  are  for 
rectangular,  open  unglazed  windows,  with  no  external 
obstructions.  The  values  shall  be  corrected  for  the 
presence  of  window  bars,  glazing  and  external 
obstructions,  if  any.  This  assumes  the  maintenance  of 
a  regular  cleaning  schedule. 

4.2. 5.2  Corrections  for  window  bars 

The  corrections  for  window  bars  shall  be  made  by 
multiplying  the  values  read  from  tables  in  Annex  B  by 
a  factor  equal  to  the  ratio  of  the  clear  opening  to  the 
overall  opening. 

4.2. 5.3  Correction  for  glazing 

Where  windows  are  glazed,  the  sky  components 
obtained  from  Annex  A  shall  be  reduced  by  10  to 
20  percent,  provided  the  panes  are  of  clear  and  clean 
glass.  Where  glass  is  of  the  frosted  (ground)  type,  the 
sky  components  read  from  Annex  A  may  be  reduced 
by  1 5  to  30  percent.  In  case  of  tinted  or  reflective  glass 
the  reduction  is  about  50  percent.  Fligher  indicated 
correction  corresponds  to  larger  windows  and/or  near 
reference  points.  In  the  case  of  openings  and  glazings 
which  are  not  vertical,  suitable  correction  shall  be  taken 
into  account. 


26 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  5  Solar  Altitudes  (to  the  Nearest  Degree)  for  Indian  Latitudes 

( Clause  4.2.1) 


Period  of  22  June  21  March  and  23  September  22  December 

Year 


Hours  of 
Day 
(Sun  or 
Solar) 
Latitude 

07  00 
17  00 

08  00 
16  00 

09  00 
15  00 

10  00 
14  00 

11  00 
13  00 

12  00 

07  00 
17  00 

08  00 
16  00 

09  00 
15  00 

10  00 
14  00 

11  00 
13  00 

12  00 

07  00 
17  00 

08  00 
16  00 

09  00 
15  00 

10  00 
14  00 

11  00 
13  00 

12  00 

(i) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

(9) 

(10) 

(ID 

(12) 

(13) 

(14) 

(15) 

(16) 

(17) 

(18) 

(19) 

10°N 

18 

31 

45 

58 

70 

77 

15 

30 

44 

59 

72 

80 

9 

23 

35 

46 

53 

57 

13°N 

19 

32 

46 

60 

72 

80 

15 

29 

44 

58 

70 

77 

8 

21 

33 

43 

51 

54 

16°N 

20 

33 

47 

61 

74 

83 

14 

29 

43 

56 

68 

74 

7 

19 

31 

41 

48 

51 

19°N 

21 

34 

48 

62 

75 

86 

14 

28 

42 

55 

66 

71 

5 

18 

29 

48 

45 

48 

22°N 

22 

35 

49 

62 

75 

89 

14 

28 

41 

53 

64 

68 

4 

16 

27 

36 

42 

45 

25°N 

23 

36 

49 

63 

76 

88 

13 

27 

40 

52 

61 

65 

3 

14 

25 

34 

39 

42 

28°N 

23 

36 

49 

63 

76 

86 

13 

26 

39 

50 

59 

62 

1 

13 

23 

31 

37 

39 

31°N 

24 

37 

50 

62 

75 

82 

13 

25 

37 

48 

56 

56 

— 

11 

21 

28 

34 

36 

34°N 

25 

37 

49 

62 

73 

79 

12 

25 

36 

46 

53 

56 

— 

9 

18 

26 

31 

33 

4.2. 5.4  Correction  for  external  obstructions  4.2.7  Internal  Reflected  Component  (IRC) 


There  is  no  separate  correction,  except  that  the  values 
from  tables  in  Annex  B  shall  be  read  only  for  the 
unobstructed  portions  of  the  window. 

4.2.6  External  Reflected  Component  (ERC) 

The  value  of  the  sky  component  corresponding  to  the 
portion  of  the  window  obstructed  by  the  external 
obstructions  may  be  found  by  the  use  of  methods 
described  in  Annex  C  of  good  practice  [8-1(3)]. 

These  values  when  multiplied  by  the  correction  factors, 
corresponding  to  the  mean  elevation  of  obstruction 
from  the  point  in  question  as  given  in  Table  6,  can  be 
taken  as  the  external  reflected  components  for  that 
point. 


The  component  of  daylight  factor  contributed  by 
reflection  from  the  inside  surfaces  varies  directly  as 
the  window  area  and  inversely  as  the  total  area  of 
internal  surfaces,  and  depends  on  the  reflection  factor 
of  the  floor,  wall  and  roof  surfaces  inside  and  of  the 
ground  outside.  For  rooms  white-washed  on  walls  and 
ceiling  and  windows  of  normal  sizes,  the  IRC  will  have 
sizeable  value  even  at  points  far  away  from  the  window. 
External  obstructions,  when  present,  will 
proportionately  reduce  IRC.  Where  accurate  values  of 
IRC  are  desired,  the  same  may  be  done  in  accordance 
with  the  good  practice  [8-1(3)]. 

4.2.8  General  Principles  of  Openings  to  Afford  Good 
Lighting 


Table  6  Correction  Factor  for  ERC 

(Clause  4.2.6) 


SI  No. 

(1) 

Mean  Angle  of  Elevation 

(2) 

Correction  Factor 

(3) 

i) 

5° 

0.086 

ii) 

15° 

0.086 

in) 

25° 

0.142 

iv) 

35° 

0.192 

v) 

45° 

0.226 

vi) 

55° 

0.274 

vii) 

65° 

0.304 

viii) 

75° 

0.324 

ix) 

85° 

0.334 

4.2.6. 1  For  method  of  calculating  ERC,  reference  may 
be  made  to  accepted  standard  (see  Examples  10  and 
11  given  in  Annex  B  of  good  practice  [8-1(3)]. 


4.2.8. 1  Generally,  while  taller  openings  give  greater 
penetrations,  broader  openings  give  better  distribution 
of  light.  It  is  preferable  that  some  area  of  the  sky  at  an 
altitude  of  20°  to  25°  should  light  up  the  working  plane. 

4.2. 8.2  Broader  openings  may  also  be  equally  or  more 
efficient,  provided  their  sills  are  raised  by  300  mm  to 
600  mm  above  the  working  plane. 

NOTE  —  It  is  to  be  noted  that  while  placing  window  with  a 
high  sill  level  might  help  natural  lighting,  this  is  likely  to  reduce 
ventilation  at  work  levels.  While  designing  the  opening  for 
ventilation  also,  a  compromise  may  be  made  by  providing  the 
sill  level  about  150  mm  below  the  head  level  of  workers. 

4.2. 8.3  For  a  given  penetration,  a  number  of  small 
openings  properly  positioned  along  the  same,  adjacent 
or  opposite  walls  will  give  better  distribution  of 
illumination  than  a  single  large  opening.  The  sky 
component  at  any  point,  due  to  a  number  of  openings 
may  be  easily  determined  from  the  corresponding  sky 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


27 


component  contour  charts  appropriately  superposed. 
The  sum  of  the  individual  sky  component  for  each 
opening  at  the  point  gives  the  overall  component  due 
to  all  the  openings.  The  same  charts  may  also  facilitate 
easy  drawing  of  sky  component  contours  due  to 
multiple  openings. 

4.2. 8.4  Unilateral  lighting  from  side  openings  will,  in 
general,  be  unsatisfactory  if  the  effective  width  of  the 
room  is  more  than  2  to  2.5  times  the  distance  from  the 
floor  to  the  top  of  the  opening.  In  such  cases  provision 
of  light  shelves  is  always  advantageous. 

4. 2. 8. 5  Openings  on  two  opposite  sides  will  give 
greater  uniformity  of  internal  daylight  illumination, 
especially  when  the  room  is  7  m  or  more  across.  They 
also  minimise  glare  by  illuminating  the  wall 
surrounding  each  of  the  opposing  openings.  Side 
openings  on  one  side  and  clerestory  openings  on  the 
opposite  side  may  be  provided  where  the  situation  so 
requires. 

4.2.8.6  Cross-lighting  with  openings  on  adjacent  walls 
tends  to  increase  the  diffused  lighting  within  a  room. 

4.2.8.7  Openings  in  deep  reveals  tend  to  minimise  glare 
effects. 

4.2.8.8  Openings  shall  be  provided  with  Chajjahs, 
louvers,  baffles  or  other  shading  devices  to  exclude,  as 
far  as  possible,  direct  sunlight  entering  the  room. 
Chajjahs,  louvers,  etc,  reduce  the  effective  height  of 
the  opening  for  which  due  allowance  shall  be  made. 
Broad  and  low  openings  are,  in  general,  much  easier 
to  shade  against  sunlight  entry.  Direct  sunlight,  when 
it  enters,  increases  the  inside  illuminance  very 
considerably.  Glare  will  result  if  it  falls  on  walls  at  low 
angles,  more  so  than  when  it  falls  on  floors,  especially 
when  the  floors  are  dark  coloured  or  less  reflective. 

4.2.8.9  Light  control  media,  such  as  translucent  glass 
panes  (opal  or  matt)  surfaced  by  grinding,  etching  or 
sandblasting,  configurated  or  corrugated  glass,  certain 
types  of  prismatic  glass,  tinted  glass  and  glass  blasts 
are  often  used.  They  should  be  provided,  either  fixed 
or  movable  outside  or  inside,  especially  in  the  upper 
portions  of  the  openings.  The  lower  portions  are  usually 
left  clear  to  afford  desirable  view.  The  chief  purpose 
of  such  fixtures  is  to  reflect  part  of  the  light  on  to  the 
roof  and  thereby  increase  the  diffuse  lighting  within, 
light  up  the  farther  areas  in  the  room  and  thereby 
produce  a  more  uniform  illumination  throughout.  They 
will  also  prevent  the  opening  causing  serious  glare 
discomfort  to  the  occupants  but  will  provide  some  glare 
when  illuminated  by  direct  sunlight. 

4.2.9  Availability  of  Daylight  in  Mnltistoreyed  Block 

Proper  planning  and  layout  of  building  can  add 
appreciably  to  daylighting  illumination  inside.  Certain 


dispositions  of  building  masses  offer  much  less  mutual 
obstruction  to  daylight  than  others  and  have  a  significant 
relevance,  especially  when  intensive  site  planning  is 
undertaken.  As  guidance,  the  relative  availability  of 
daylight  in  multi-storeyed  blocks  (up  to  4  storeys)  of 
different  relative  orientations  may  be  taken  as  given  in 
Table  7. 

Table  7  Relative  Availability  of  Daylight  on  the 
Window  Plane  at  Ground  Level  in  a 
Four-Storeyed  Building  Blocks  (Clear  Design-Sky 
as  Basis,  Daylight  Availability  Taken  as  Unity  on 
an  Unobstructed  Facade,  Values  are  for  the 
Centre  of  the  Blocks) 

( Clause  4.2.9) 


SI 

Distance  of 

Infinitely 

Parallel 

Parallel  Blocks 

No. 

Separation 

Long 

Blocks 

facing  Gaps 

Between 

Parallel 

Facing  Each 

Between 

Blocks 

Blocks 

Other 

Opposite 

(Length  = 

Blocks 

2  x  Height) 

(Length  = 

2  x  Height) 

(1) 

(2) 

(3) 

(4) 

(5) 

i) 

0.5  Ht 

0.15 

0.15 

0.25 

ii) 

1.0  Ht 

0.30 

0.32 

0.38 

iii) 

1.5  Ht 

0.40 

0.50 

0.55 

iv) 

2.0  Ht 

0.50 

0.60 

0.68 

NOTE  —  Ht  =  Height  of  building. 


4.2.10  For  specified  requirements  for  daylighting  of 
special  occupancies  and  areas,  reference  may  be  made 
to  good  practice  [8-1(4)]. 

4.3  Artificial  Lighting 

4.3.1  Artificial  lighting  may  have  to  be  provided, 

a)  where  the  recommended  illumination  levels 
have  to  be  obtained  by  artificial  lighting  only; 

b)  to  supplement  daylighting  when  the  level  of 
illumination  falls  below  the  recommended 
value;  and 

c)  where  visual  task  may  demand  a  higher  level 
of  illumination. 

4.3.2  Artificial  Lighting  Design  for  Interiors 

For  general  lighting  purposes,  the  recommended 
practice  is  to  design  for  a  level  of  illumination  on  the 
working  plane  on  the  basis  of  the  recommended  levels 
for  visual  tasks  given  in  Table  4  by  a  method  called 
‘Lumen  method’.  In  order  to  make  the  necessary 
detailed  calculations  concerning  the  type  and  quantity 
of  lighting  equipment  necessary,  advance  information 
on  the  surface  reflectances  of  walls,  ceilings  and  floors 
is  required.  Similarly,  calculations  concerning  the 
brightness  ratio  in  the  interior  call  for  details  of  the 
interior  decoration  and  furnishing.  Stepwise  guidance 
regarding  designing  the  interior  lighting  systems  for  a 


28 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


building  using  the  ‘Lumen  method’  is  given  in  4.3.2. 1 
to  4.3.2.4. 

4.3.2. 1  Determination  of  the  illumination  level 

Recommended  value  of  illumination  shall  be  taken  from 
Table  4,  depending  upon  the  type  of  work  to  be  carried 
out  in  the  location  in  question  and  the  visual  tasks 
involved. 

4.3.2.2  Selection  of  the  light  sources  and  luminaires 

The  selection  of  light  sources  and  luminaires  depends 
on  the  choice  of  lighting  system,  namely,  general 
lighting,  directional  lighting  and  localized  or  local 
lighting. 

4.3.2.3  Determination  of  the  luminous  flux 

a)  The  luminous  flux  ( F)  reaching  the  working 
plane  depends  upon  the  following: 

1 )  Lumen  output  of  the  lamps, 

2)  Type  of  luminaire, 

3)  Proportion  of  the  room  (room  index)  (kt), 

4)  Reflectance  of  internal  surfaces  of  the 
room, 

5)  Depreciation  in  the  lumen  output  of  the 
lamps  after  burning  their  rated  life,  and 

6)  Depreciation  due  to  dirt  collection  on 
luminaires  and  room  surface. 

b)  Coefficient  of  utilization  or  utilization  factor 
1)  The  compilation  of  tables  for  the 

utilization  factor  requires  a  considerable 
amount  of  calculations,  especially  if  these 
tables  have  to  cover  a  wide  range  of 
lighting  practices.  For  every  luminaire, 
the  exact  light  distribution  has  to  be 
measured  in  the  laboratory  and  their 
efficiencies  have  to  be  calculated  and 
measured  exactly.  These  measurements 
comprise, 

i)  the  luminous  flux  radiated  by  the 
luminaires  directly  to  the  measuring 
surface; 

ii)  the  luminous  flux  reflected  and  re- 
reflected  by  the  ceiling  and  the  walls 
to  the  measuring  surface;  and 

iii)  the  inter-reflections  between  the 
ceiling  and  wall  which  result  in  the 
measuring  surface  receiving 
additional  luminous  flux. 

All  these  measurements  have  to  be  made 
for  different  reflection  factors  of  the 
ceiling  and  the  walls  for  all  necessary 
room  indices.  These  tables  have  also  to 
indicate  the  maintenance  factor  to  be 
taken  for  the  luminous  flux  depreciation 


throughout  the  life  of  an  installation  due 
to  ageing  of  the  lamp  and  owing  to  the 
deposition  of  dirt  on  the  lamps  and 
luminaires  and  room  surfaces. 

2)  The  values  of  the  reflection  factor  of  the 
ceiling  and  of  the  wall  are  as  follows: 


White  and  very  light  colours  :  0.7 

Light  colours  :  0.5 

Middle  tints  :  0.3 

Dark  colours  :  0.1 


For  the  walls,  taking  into  account  the 
influence  of  the  windows  without 
curtains,  shelves,  almirahs  and  doors  with 
different  colours,  etc,  should  be 
estimated. 

c)  Calculation  for  determining  the  luminous  flux 
[see  Table  22  of  SP  :  41  (S&T)  —  1987 
‘Handbook  on  functional  requirements  of 
buildings  other  than  industrial  buildings' ] 

E  -H4 
av_  A 

E.  .A 

or,  <|)  =  av’  ,  for  new  condition,  and 

U 


4)  =  av'  ,  for  working  condition 

M 

where 

(f>  =  total  luminous  flux  of  the  light  sources 

installed  in  the  room,  in  lumens; 

Em  =  average  illumination  level  required  on  the 
working  plane,  in  lux; 

A  =  area  of  the  working  plane,  in  m2; 
p  =  utilization  factor  in  new  conditions;  and 
d  =  maintenance  factor. 

In  practice,  it  is  easier  to  calculate  straightaway  the 
number  of  lamps  or  luminaires  from: 


^lamp 

Em.A 

N,  ■  ■  =  E™'A 

T  luminaires  »  . 

^  -t  luminaires 

where 

Tlamp 

luminous  flux  of  each  lamp,  in 
lumens 

^luminaires 

luminous  flux  of  each  luminaire,  in 
lumens 

^lamp 

total  number  of  lamps 

^luminaires 

total  number  of  luminaires. 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


29 


43.2.4  Arrangement  of  the  luminaires 

This  is  done  to  achieve  better  uniformly  distributed 
illumination.  The  location  of  the  luminaires  has  an 
important  effect  on  the  utilization  factor. 

a)  In  general,  luminaires  are  spaced  V  metre 
apart  in  either  direction,  while  the  distance  of 
the  end  luminaire  from  the  wall  is  ‘0.5x’  metre. 
The  distance  V  is  more  or  less  equal  to  the 
mounting  height '  Hf  between  the  luminaire 
and  the  working  plane.  The  utilization  factor 
tables  are  calculated  for  this  arrangement  of 
luminaires  [see  Table  22  of  SP  :  41  (S&T)  - 
1987  ‘Handbook  on  functional  requirements 
of  buildings  other  than  industrial  buildings’], 

b)  For  small  rooms  where  the  room  index  ( kt )  is 
less  than  1 ,  the  distance  V  should  always  be 
less  than  Hm,  since  otherwise  luminaires 
cannot  be  properly  located.  In  most  cases  of 
such  rooms,  four  or  two  luminaires  are  placed 
for  good  general  lighting.  If,  however,  in  such 
rooms  only  one  luminaire  is  installed  in  the 
middle,  higher  utilization  factors  are  obtained, 
but  the  uniformity  of  distribution  is  poor.  For 
such  cases,  references  should  be  made  to  the 
additional  tables  for  ki  =  0.6  to  1.25  for 
luminaires  located  centrally. 

4.3.3  Artificial  Lighting  to  Supplement  Daylighting 

4.3.3. 1  The  need  for  general  supplementary  artificial 
lighting  arises  due  to  diminishing  of  daylighting  beyond 


design  hours,  that  is,  for  solar  altitude  below  15°  or 
when  dark  cloudy  conditions  occur. 

4.33.2  The  need  may  also  arise  for  providing  artificial 
lighting  during  the  day  in  the  innermost  parts  of  the 
building  which  cannot  be  adequately  provided  with 
daylighting,  or  when  the  outside  windows  are  not  of 
adequate  size  or  when  there  are  unavoidable  external 
obstructions  to  the  incoming  daylighting. 

4.3.33  The  need  for  supplementary  lighting  during 
the  day  arises,  particularly  when  the  daylighting  on  the 
working  plane  falls  below  100  lux  and  the  surrounding 
luminance  drops  below  19  cd/m2. 

4.33.4  The  requirement  of  supplementary  artificial 
lighting  increases  with  the  decrease  in  daylighting 
availability.  Therefore,  conditions  near  sunset  or  sunrise 
or  equivalent  conditions  due  to  clouds  or  obstructions, 
etc,  represent  the  worst  conditions  when  the 
supplementary  lighting  is  most  needed. 

4.33.5  The  requirement  of  supplementary  artificial 
lighting  when  daylighting  availability  becomes  poor 
may  be  determined  from  Fig.  3  for  an  assumed  ceiling 
height  of  3.0  m,  depending  upon  floor  area,  fenestration 
percentage  and  room  surface  reflectance.  Cool  daylight 
fluorescent  tubes  are  recommended  with  semi-direct 
luminaires.  To  ensure  a  good  distribution  of 
illumination,  the  mounting  height  should  be  between 

1.5  m  and  2.0  m  above  the  work  plane  for  a  separation 
of  2.0  m  to  3.0  m  between  the  luminaires.  Also  the 
number  of  lamps  should  preferably  be  more  in  the  rear 
half  of  the  room  than  in  the  vicinity  of  windows.  The 


co 

LLI 

lO 


LU 

O 

CO 

LU 

C£ 

O 

Z) 


o 

'3- 


o 

DC 

LU 

CO 


25  n 


20- 


15- 


10- 


5  - 


3  0 


REFLECTANCE 

CEILING 

WALLS 

FLOOR 

0.7 

0.7 

0.3 

— 

0.7 

0.5 

0.3 

0.5 

0.5 

0.3 

OPENINGS, 

PERCENT 

.  5 

'  -10 


0 


“I - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - [ - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 - 1 

50  100  150  200  230 


FLOOR  AREA,  m2 

Fig.  3  Supplementary  Artificial  Lighting  for  40  W  Fluorescent  Tubes 


30 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


following  steps  may  be  followed  for  using  Fig.  3  for 
determining  the  number  of  fluorescent  tubes  required 
for  supplementary  daylighting. 

a)  Determine  fenestration  percentage  of  the  floor 
area,  that  is, 

Window  area  , 

-  x  100 

Floor  area 

b)  In  Fig.  3,  refer  to  the  curve  corresponding  to 
the  percent  fenestration  determined  above  and 
the  set  of  reflectances  of  ceiling,  walls  and 
floor  actually  provided. 

c)  For  the  referred  curve  of  Fig.  3  read,  along 
the  ordinate,  the  number  of  40  W  fluorescent 
tubes  required,  corresponding  to  the  given 
floor  area  on  the  abscissa. 

4.3.4  For  detailed  information  on  the  design  aspects 
and  principles  of  artificial  lighting,  reference  may  be 
made  to  good  practice  [8-1(2)]. 

4.3.5  For  specific  requirements  for  lighting  of  special 
occupancies  and  areas,  reference  may  be  made  to  good 
practice  [8-1(5)]. 

4.3.6  Electrical  installation  aspect  for  artificial  lighting 
shall  be  in  accordance  with  Part  8  ‘Building  Services, 
Section  2  Electrical  and  Allied  Installations’  of  the 
Code. 

4.4  Energy  Conservation  in  Lighting 

4.4.1  A  substantial  portion  of  the  energy  consumed  on 
lighting  may  be  saved  by  utilization  of  daylight  and 
rational  design  of  supplementary  artificial  lights. 

4.4.2  Daytime  use  of  artificial  lights  may  be  minimised 
by  proper  design  of  windows  for  adequate  daylight 
indoors.  Daylighting  design  should  be  according  to  4.2. 

4.4.3  Fenestration  expressed  as  percentage  of  floor  area 
required  for  satisfactory  visual  performance  of  a  few 
tasks  for  different  separation  to  height  (S/H)  ratio  of 
external  obstructions  such  as  opposite  buildings  may 
be  obtained  from  the  design  nomogram  (see  Fig.  4). 
The  obstructions  at  a  distance  of  three  times  their  height 
or  more  ( S/H  >3)  from  a  window  fapade  are  not 
significant  and  a  window  facing  such  an  obstruction 
may  be  regarded  as  a  case  of  unobstructed  window. 

4.4.3. 1  The  nomogram  consists  of  horizontal  lines 
indicating  fenestration  percentage  of  floor  area  and 
vertical  lines  indicating  the  separation  to  height  ratio 
of  external  obstructions  such  as  opposite  buildings.  Any 
vertical  line  for  separation  to  height  ratio  other  than 
already  shown  in  the  nomogram  ( 1 .0,  2.0  and  3.0)  may 
be  drawn  by  designer,  if  required.  For  cases  where  there 
is  no  obstruction,  the  ordinate  corresponding  to  the 
value  3.0  may  be  used.  The  value  of  percentage 


fenestration  and  separation  to  height  ratio  are  marked 
on  left  hand  ordinate  and  abscissa,  respectively.  The 
illumination  levels  are  marked  on  the  right  hand 
ordinate.  The  values  given  within  brackets  are  the 
illumination  levels  on  the  work  plane  at  center  and  rear 
of  the  room.  The  wattage  of  fluorescent  tubes  required 
per  m2  of  the  floor  area  for  different  illumination  levels 
is  shown  on  each  curve. 

4.4.3.2  Following  assumptions  have  been  made  in  the 
construction  of  the  nomogram: 

a)  An  average  interior  finish  with  ceiling  white, 
walls  off  white  and  floor  grey  has  been 
assumed. 

b)  Ceiling  height  of  3  m,  room  depths  up  to  1 0  m 
and  floor  area  between  30  m2  and  50  m2  have 
been  assumed.  For  floor  area  beyond  50  m2 
and  less  than  30  m2,  the  values  of  percent 
fenestration  as  well  as  wattage  per  m2  should 
be  multiplied  by  a  factor  of  0.85  and  1.15, 
respectively. 

c)  It  is  assumed  that  windows  are  of  metallic 
sashes  with  louvers  of  width  up  to  600  mm  or 
a  Chhajja  (balcony  projection)  at  ceiling  level 
of  width  up  to  2.0  m.  For  wooden  sashes,  the 
window  area  should  be  increased  by  a  factor 
of  about  1.1. 

d)  Luminaires  emanating  more  light  in  the 
downward  direction  than  upward  direction 
(such  as  reflectors  with  or  without  diffusing 
plastics)  and  mounted  at  a  height  of  1.5  m  to 
2.0  m  above  the  work  plane  have  been 
considered. 

4.4.3.3  Method  of  use 

The  following  steps  shall  be  followed  for  the  use  of 
nomogram: 

a)  Step  1  —  Decide  the  desired  illumination  level 
depending  upon  the  task  illumination 
requirement  in  the  proposed  room  and  read 
the  value  of  watts  per  m2  on  the  curve 
corresponding  to  the  required  illumination 
level. 

b)  Step  2  —  Fix  the  vertical  line  corresponding 
to  the  given  separation  to  height  ratio  of 
opposite  buildings  on  the  abscissa.  From  the 
point  of  intersection  of  this  vertical  line  and 
the  above  curve  move  along  horizontal,  and 
read  the  value  of  fenestration  percent  on  the 
left  hand  ordinate. 

c)  Step  3  —  If  the  floor  area  is  greater  than  50  m2 
or  if  it  is  less  than  30  m2,  the  value  of  watt  per 
m2  as  well  as  fenestration  percent  may  be 
easily  determined  for  adequate  daylighting 
and  supplemental  artificial  lighting  for  design 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


31 


(360,  200) 
200 

(320,  175) 
175 

(280,  150) 
150 

(240,  125) 
125 

(200,  100) 

100 

(150,  75) 
75 


1.0 


2.0 


3.0 


SEPARATION  TO  HEIGHT  RATIO 

Fig.  4  Nomograph  for  Daylighting  and  Supplemental  Lighting  Design  of  Buildings 


32 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


WORK  PLANE  ILLUMINATION  (LUX)  INCLUSIVE  OF  SUPPLEMENTAL 
LIGHTS  DURING  POOR  DAYLIGHT  CONDITIONS 


purposes.  However,  if  the  fenestration 
provided  is  less  than  the  required  value,  the 
wattage  of  supplementary  artificial  lights 
should  be  increased  proportionately  to  make 
up  for  the  deficiency  of  natural  illumination. 

4.4.4  For  good  distribution  of  day  light  on  the  working 
plane  in  a  room,  window  height,  window  width  and 
height  of  sill  should  be  chosen  in  accordance  with  the 
following  recommendations: 

a)  In  office  buildings  windows  of  height  1 .2  m 
or  more  in  the  centre  of  a  bay  with  sill  level  at 
1.0  to  1.2  m  above  floor  and  in  residential 
buildings  windows  of  height  1.0  m  to  1.1  m 
with  sill  height  as  0.7  m  to  0.9  m  above  floor 
are  recommended  for  good  distribution  of 
daylight  indoors.  Window  width  can 
accordingly  be  adjusted  depending  upon  the 
required  fenestration  percentage  of  the  floor 
area. 

b)  If  the  room  depth  is  more  than  10  m,  windows 
should  be  provided  on  opposite  sides  for 
bilateral  lighting. 

c)  It  is  desirable  to  have  a  white  finish  for  ceiling 
and  off  white  (light  colour)  to  white  for  walls. 
There  is  about  7  percent  improvement  in 
lighting  levels  in  changing  the  finish  of  walls 
from  moderate  to  white. 

4.4.5  For  good  distribution  and  integration  of  daylight 
with  artificial  lights  the  following  guidelines  are 
recommended: 

a)  Employ  cool  daylight  fluorescent  tubes  for 
supplementary  artificial  lighting. 

b)  Distribute  luminaries  with  a  separation  of  2  m 
to  3  m  in  each  bay  of  3  m  to  4  m  width. 

c)  Provide  more  supplementary  lights  such  as 
twin  tube  luminaries  in  work  areas  where 
daylight  is  expected  to  be  poor,  for  example 
in  the  rear  region  of  a  room  having  single 
window  and  in  the  central  region  of  a  room 
having  windows  on  opposite  walls.  In  the 
vicinity  of  windows  only  single  tube 
luminaries  should  be  provided. 

4.4.6  Artificial  Lighting 

Energy  conservation  in  lighting  is  affected  by  reducing 
wastage  and  using  energy  effective  lamps  and 
luminaires  without  sacrificing  lighting  quality. 
Measures  to  be  followed  comprise  utilization  of 
daylight,  energy  effective  artificial  lighting  design  by 
providing  required  illumination  where  needed,  turning 
off  artificial  lights  when  not  needed,  maintaining  lighter 
finishes  of  ceiling,  walls  and  furnishings,  and 
implementing  periodic  schedule  for  cleaning  of 


luminaires  and  group  replacement  of  lamps  at  suitable 
intervals.  Choice  of  light  sources  with  higher  luminous 
efficacy  and  luminaires  with  appropriate  light 
distribution  is  the  most  effective  means  of  energy  saving 
in  lighting.  However,  choice  of  light  sources  also 
depends  on  the  other  lighting  quality  parameters  like 
colour  rendering  index  and  colour  temperature  or 
appearance.  For  example,  high  pressure  sodium  vapour 
lamps,  which  have  very  high  luminous  efficacy,  are  not 
suitable  for  commercial  interiors  because  of  poor  colour 
rendering  index  and  colour  appearance,  but  are  highly 
desirable  in  heavy  industries.  Also  the  choice  of  light 
sources  depends  on  the  mounting  height  in  the  interiors. 
For  example,  fluorescent  lamps  are  not  preferred  for 
mounting  beyond  7  m  height,  when  high  pressure  gas 
discharge  lamps  are  preferred  because  of  better  optical 
control  due  to  their  compact  size. 

4.4.6.1  Efficient  artificial  light  sources  and  luminaires 

Luminous  efficacies  of  some  of  the  lamps  used  in 
lighting  of  buildings  are  given  in  Table  8  along  with 
average  life  in  burning  hours,  colour  rendering  index 
and  colour  temperature. 

Following  recommendations  may  be  followed  in  the 
choice  of  light  sources  for  different  locations: 

a)  For  supplementary  artificial  lighting  of  work 
area  in  office  building  care  should  be  taken  to 
use  fluorescent  lamps,  which  match  with 
colour  temperature  of  the  daylight. 

b)  For  residential  buildings  fluorescent  lamps 
and/or  CFLs  of  proper  CRI  and  CCT  are 
recommended  to  match  with  the  colours  and 
interior  design  of  the  room. 

c)  For  commercial  interiors,  depending  on  the 
mounting  heights  and  interior  design, 
fluorescent  lamps,  CFLs  and  low  wattage 
metal  halide  lamps  are  recommended.  For 
highlighting  the  displays  in  show  windows, 
hotels,  etc,  low  wattage  tubular  or  dichroic 
reflector  type  halogen  lamps  can  be  used. 

d)  For  industrial  lighting,  depending  on  the 
mounting  height  and  colour  consideration 
fluorescent  lamps,  high  pressure  mercury 
vapour  lamps  or  high  pressure  sodium  vapour 
lamps  are  recommended. 

4.4.6.2  For  the  same  lumen  output,  it  is  possible  to 
save  50  to  70  percent  energy  if  CFL  lamps  are  replaced 
with  induction  lighting,  and  40  to  60  percent  if  replaced 
with  LED  lamps.  Similar  energy  effective  solutions  are 
to  be  chosen  for  every  application  area. 

Similarly  with  white  fluorescent  tubes  recommended 
for  corridors  and  staircases,  the  electrical  consumption 
reduces  to  1/4.5  of  the  energy  consumption  with 
incandescent  lamps. 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


33 


Table  8  Luminous  Efficacy,  Life,  Lumen  Maintenance  and  Colour  Rendition  of  Light  Sources 

( Clause  4.4.6. 1) 


SI 

Light  Source 

Wattage 

Efficacy 

Average  Life 

Lumen 

Colour  Rendition 

No. 

Range 

W 

lm/W 

h 

Maintenance 

(1) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

0 

Incandescent  lamps 

15  to  200 

12  to  20 

500  to  1  000 

Fair  to  good 

Very  good 

ii) 

Tungsten  halogen 

300  to  1  500 

20  to  27 

200  to  2  000 

Good  to  very  good 

Very  good 

iii) 

Standard  fluorescent  lamps 

20  to  80 

55  to  65 

5  000 

Fair  to  good 

Good 

iv) 

Compact  fluorescent  lamps  (CFL) 

5  to  40 

60  to  70 

7  500 

Good 

Good  to  very  good 

v) 

Slim  line  fluorescent 

18  to  58 

57  to  67 

5  000 

Fair  to  good 

Good 

v) 

High  pressure  mercury  vapour  lamps 

60  to  1  000 

50  to  65 

5  000 

Very  low  to  fair 

Federate 

vi) 

Blended  -  light  lamps 

160  to  250 

20  to  30 

5  000 

Low  to  fair 

Federate 

vii) 

High  pressure  sodium  vapour  lamps 

50  to  1  000 

90  to  125 

10  000  to  15  000 

Fair  to  good 

Low  to  good 

viii) 

Metal  halide  lamps 

35  to  2  000 

80  to  95 

4  000  to  10  000 

Very  low 

Very  good 

ix) 

Low  pressure  sodium 

10  to  180 

100  to  200 

10  000  to  20  000 

Good  to  very  good 

Poor 

x) 

LED 

0.5  to  2.0 

60  to  100 

10  000 

Very  good 

Good  for  white  LED 

NOTES 

1  The  table  includes  lamps  and  wattages  currently  in  use  in  buildings  in  India. 

2  Luminous  efficacy  varies  with  the  wattage  of  the  lamp. 

3  Average  life  values  are  from  available  Indian  Standards.  Where  Indian  Standard  is  not  available,  values  given  are  only  indicative. 

4  For  exact  values,  it  is  advisable  to  contact  manufacturers. 


4.4.6.3  Efficient  luminaire  also  plays  an  important  role 
for  energy  conservation  in  lighting.  The  choice  of  a 
luminaire  should  be  such  that  it  is  efficient  not  only 
initially  but  also  throughout  its  life.  Following 
luminaries  are  recommended  for  different  locations: 

a)  For  offices  semi-direct  type  of  luminaries  are 
recommended  so  that  both  the  work  plane 
illumination  and  surround  luminance  can  be 
effectively  enhanced. 

b)  For  corridors  and  stair  cases  direct  type  of 
luminaries  with  wide  spread  of  light 
distributions  are  recommended. 

c)  In  residential  buildings,  bare  fluorescent  tubes 
are  recommended.  Wherever  the  incandescent 
lamps  are  employed,  they  should  be  provided 
with  white  enameled  conical  reflectors  at  an 
inclination  of  about  45°  from  vertical. 

4.4.7  Cleaning  Schedule  for  Window  Panes  and 
Luminaires 

Adequate  schedule  for  cleaning  of  window  panes  and 
luminaries  will  result  in  significant  advantage  of 
enhanced  daylight  and  lumen  output  from  luminaries. 
This  will  tend  to  reduce  the  duration  over  which 
artificial  lights  will  be  used  and  minimise  the  wastage 
of  energy.  Depending  upon  the  location  of  the  building 
a  minimum  of  three  to  six  months  interval  for  periodic 
cleaning  of  luminaries  and  window  panes  is 


recommended  for  maximum  utilization  of  daylight  and 
artificial  lights. 

4.4.8  Photocontrols  for  Artificial  Lights 

There  is  a  considerable  wastage  of  electrical  energy  in 
lighting  of  buildings  due  to  carelessness  in  switching 
off  lights  even  when  sufficient  daylight  is  available 
indoors.  In  offices  and  commercial  buildings,  occupants 
may  switch  on  lights  in  the  morning  and  keep  them  on 
throughout  the  day.  When  sufficient  daylight  is 
available  inside,  suitable  photo  controls  can  be 
employed  to  switch  off  the  artificial  lights  and  thus 
prevent  the  wastage  of  energy. 

The  photocontrol  should  have  the  following  features: 

a)  An  integrated  photocontrol  system  continually 
measures  the  amount  of  visible  light  under  the 
lighting  fixture  and  maintains  the  lux  levels 
as  referred  in  Table  4. 

b)  An  integrated  photocontrol  system  should 
maintain  six  daylighting  scenarios  that  can  be 
adjusted  by  the  user  namely;  daytime 
occupied,  daytime  unoccupied,  sunset 
occupied,  sunset  unoccupied,  night  time 
occupied  and  night  time  unoccupied. 

c)  The  photocontrol  sensor  should  have 
a  60°  cone  of  reference  to  measure  the  amount 
of  light  on  the  work  surface. 


34 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


4.4.9  Solar  Photovoltaic  Systems  (SPV) 

Solar  photovoltaic  system  enables  direct  conversion  of 
sunlight  into  electricity  and  is  a  viable  option  for 
lighting  purpose  in  remote  nongrid  areas.  The  common 
SPV  lighting  systems  are: 

a)  Solar  lantern, 

b)  Fixed  type  solar  home  lighting  system,  and 

c)  Street  lighting  system. 

4.4.9. 1  SPV  lighting  system  should  preferably  be 
provided  with  CFL  for  energy  efficiency. 

4. 4. 9. 2  Inverters  used  in  buildings  for  supplying 
electricity  during  the  power  cut  period  should  be 
charged  through  SPV  system. 

4. 4. 9. 3  Regular  maintenance  of  SPV  system  is 
necessary  for  its  satisfactory  functioning. 

4.4.10  Lighting  shelves  and  light  pipes  may  be  explored 
for  utilization  and  integration  in  the  lighting  design. 

5  VENTILATION 

5.1  General 

Ventilation  of  buildings  is  required  to  supply  fresh  air 
for  respiration  of  occupants,  to  dilute  inside  air  to 
prevent  vitiation  by  body  odours  and  to  remove  any 
products  of  combustion  or  other  contaminants  in  air 
and  to  provide  such  thermal  environments  as  will  assist 
in  the  maintenance  of  heat  balance  of  the  body  in  order 
to  prevent  discomfort  and  injury  to  health  of  the 
occupants. 

5.2  Design  Considerations 

5.2.1  Respiration 

Supply  of  fresh  air  to  provide  oxygen  for  the  human 
body  for  elimination  of  waste  products  and  to  maintain 
carbon  dioxide  concentration  in  the  air  within  safe  limits 
rarely  calls  for  special  attention  as  enough  outside  air 
for  this  purpose  normally  enters  the  areas  of  occupancy 
through  crevices  and  other  openings. 

5.2. 1.1  In  normal  habitable  rooms  devoid  of  smoke 
generating  source,  the  content  of  carbon  dioxide  in  air 
rarely  exceeds  0.5  percent  to  1  percent  and  is,  therefore, 
incapable  of  producing  any  ill  effect.  The  amount  of 
air  required  to  keep  the  concentration  down  to  1  percent 
is  very  small.  The  change  in  oxygen  content  is  also  too 
small  under  normal  conditions  to  have  any  ill  effects; 
the  oxygen  content  may  vary  quite  appreciably  without 
noticeable  effect,  if  the  carbon  dioxide  concentration 
is  unchanged. 

5.2.2  Vitiation  by  Body  Odours 

Where  no  products  of  combustion  or  other 


contaminants  are  to  be  removed  from  air,  the  amount 
of  fresh  air  required  for  dilution  of  inside  air  to  prevent 
vitiation  of  air  by  body  odours,  depends  on  the  air  space 
available  per  person  and  the  degree  of  physical  activity; 
the  amount  of  air  decreases  as  the  air  space  available 
per  person  increases,  and  it  may  vary  from  20  m3  to 
30  m3  per  person  per  hour.  In  rooms  occupied  by  only 
a  small  number  of  persons  such  an  air  change  will 
automatically  be  attained  in  cool  weather  by  normal 
leakage  around  windows  and  other  openings  and  this 
may  easily  be  secured  in  warm  weather  by  keeping  the 
openings  open. 

No  standards  have  been  laid  down  under  Factories  Act, 
1948  as  regards  the  amount  of  fresh  air  required  per 
worker  or  the  number  of  air  changes  per  hour.  Section 
16  of  the  Factories  Act,  1948  relating  to  overcrowding 
requires  that  at  least  14  m3  to  16  m3  of  space  shall  be 
provided  for  every  worker  and  for  the  purpose  of  that 
section  no  account  shall  be  taken  of  any  space  in  a  work 
room  which  is  more  than  4.25  m  above  the  floor  level. 

NOTE  —  Vitiation  of  the  atmosphere  can  also  occur  in  factories 
by  odours  given  off  due  to  contaminants  of  the  product  itself, 
say  for  example,  from  tobacco  processing  in  a  ‘Beedi’  factory. 
Here  the  ventilation  will  have  to  be  augmented  to  keep  odours 
within  unobjectionable  levels. 

5.2.2. 1  Recommended  values  for  air  changes 

The  standards  of  general  ventilation  are  recommended/ 
based  on  maintenance  of  required  oxygen,  carbon 
dioxide  and  other  air  quality  levels  and  for  the  control 
of  body  odours  when  no  products  of  combustion  or 


other  contaminants  are  present  in  the 
air  changes  should  be  as  follows: 

air;  the  values  of 

SI  No. 

Application  Air  Change  per  Flour 

(1) 

(2) 

(3) 

1. 

Assembly  rooms 

4-8 

2. 

Bakeries 

20-30 

3. 

Banks/building  societies 

4-8 

4. 

Bathrooms 

6-10 

5. 

Bedrooms 

2-4 

6. 

Billiard  rooms 

6-8 

7. 

Boiler  rooms 

see  Note  2 

8. 

Cafes  and  coffee  bars 

10-12 

9. 

Canteens 

8-12 

10. 

Cellars 

3-10 

11. 

Changing  rooms 

6-10 

12. 

Churches 

1-3 

13. 

Cinemas  and  theatres 

10-15 

14. 

Club  rooms 

12,  Min 

15. 

Compressor  rooms 

10-12 

16. 

Conference  rooms 

8-12 

17. 

Corridors 

5-10 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


35 


SI  No. 

Application  Air  Change  per  Hour 

(1) 

(2) 

(3) 

18. 

Dairies 

8-12 

19. 

Dance  halls 

12,  Min 

20. 

Dye  works 

20-30 

21. 

Electroplating  shops 

10-12 

22. 

Engine  rooms/DG 

Rooms/GG  Rooms 

see  Note  2 

23. 

Entrance  halls 

3-5 

24. 

Factories  and  work  shops 

8-10 

25. 

Foundries 

15-30 

26. 

Garages 

6-8 

27. 

Glass  houses 

25-60 

28. 

Gymnasium 

6,  Min 

29. 

Hair  dressing  saloon 

10-15 

30. 

Hospitals  sterilising 

15-25 

31. 

Hospital  wards 

6-8 

32. 

Hospital  domestic 

15-20 

33. 

Laboratories 

6-15 

34. 

Launderettes 

10-15 

35. 

Laundries 

10-30 

36. 

Lavatories 

6-15 

37. 

Lecture  theatres 

5-8 

38. 

Libraries 

3-5 

39. 

Lift  cars 

20,  Min 

40. 

Living  rooms 

3-6 

41. 

Mushroom  houses 

6-10 

42. 

Offices 

6-10 

43. 

Paint  shops  (not  cellulose) 

10-20 

44. 

Photo  and  X-ray  dark  room 

10-15 

45. 

Public  house  bars 

12,  Min 

46. 

Recording  control  rooms 

15-25 

47. 

Recording  studios 

10-12 

48. 

Restaurants 

8-12 

49. 

Schoolrooms 

5-7 

50. 

Shops  and  supermarkets 

8-15 

51. 

Shower  baths 

15-20 

52. 

Stores  and  warehouses 

3-6 

53. 

STP  rooms 

30,  Min 

54. 

Squash  courts 

4,  Min 

55. 

Swimming  baths 

10-15 

56. 

Toilets 

6-10 

57. 

Underground  vehicle  parking 

6,  Min 

58. 

Utility  rooms 

15-30 

59. 

Welding  shops 

15-30 

NOTES 

1  The  ventilation  rates  may  be  increased  by  50  percent  where 
heavy  smoking  occurs  or  if  the  room  is  below  the  ground. 

2  The  ventilation  rate  shall  be  as  per  11.2.2  of  Part  8  ‘Building 
Services,  Section  3  Air  Conditioning,  Heating  and  Mechanical 
Ventilation’  of  the  Code. 


5.2.3  Heat  Balance  of  Body 

Especially  in  hot  weather,  when  thermal  environment 
inside  the  room  is  worsened  by  heat  given  off  by 
machinery,  occupants  and  other  sources,  the  prime  need 
for  ventilation  is  to  provide  such  thermal  environment 
as  will  assist  in  the  maintenance  of  heat  balance  of  the 
body  in  order  to  prevent  discomfort  and  injury  to  health. 
Excess  of  heat  either  from  increased  metabolism  due 
to  physical  activity  of  persons  or  gains  from  a  hot 
environment  has  to  be  offset  to  maintain  normal  body 
temperature  (37°C).  Heat  exchange  of  the  human  body 
with  respect  to  the  surroundings  is  determined  by  the 
temperature  and  humidity  gradient  between  the  skin 
and  the  surroundings  and  other  factors,  such  as  age  of 
persons,  clothing,  etc,  and  the  latter  depends  on  air 
temperature  (dry  bulb  temperature),  relative  humidity, 
radiation  from  the  solid  surroundings  and  rate  of  air 
movement.  The  volume  of  outside  air  to  be  circulated 
through  the  room  is,  therefore,  governed  by  the  physical 
considerations  of  controlling  the  temperature,  air 
distribution  or  air  movement.  Air  movement  and  air 
distribution  may,  however,  be  achieved  by  recirculation 
of  the  inside  air  rather  than  bringing  in  all  outside  air. 
However,  fresh  air  supply  or  the  circulated  air  will 
reduce  heat  stress  by  dissipating  heat  from  body  by 
evaporation  of  the  sweat,  particularly  when  the  relative 
humidity  is  high  and  the  air  temperature  is  near  body 
temperature. 

5.2.3. 1  Indices  of  thermal  comfort 

Thermal  comfort  is  that  condition  of  thermal 
environment  under  which  a  person  can  maintain  a  body 
heat  balance  at  normal  body  temperature  and  without 
perceptible  sweating.  Limits  of  comfort  vary 
considerably  according  to  studies  carried  out  in  India 
and  abroad. 

The  thermal  indices  which  find  applications  for  Indian 
climate  are  as  follows: 

a)  Effective  temperature  (ET), 

b)  Tropical  summer  index  (TSI),  and 

c)  Adaptive  thermal  comfort. 

5.2.3. 1.1  Effective  temperature  (ET) 

Effective  temperature  is  defined  as  the  temperature  of 
still,  saturated  air  which  has  the  same  general  effect 
upon  comfort  as  the  atmosphere  under  investigation. 
Combinations  of  temperature,  humidity  and  wind 
velocity  producing  the  same  thermal  sensation  in  an 
individual  are  taken  to  have  the  same  effective 
temperature. 

Initially  two  scales  were  developed,  one  of  which 
referred  to  men  stripped  to  the  waist,  and  called  the 
basic  scale.  The  other  applies  to  men  fully  clad  in  indoor 
clothing  and  called  the  normal  scale  of  effective 


36 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


temperature.  Bedfort  (1946)  proposed  the  use  of  globe 
temperature  reading  instead  of  the  air  temperature 
reading  to  make  allowance  for  the  radiant  heat.  This 
scale  is  known  as  the  corrected  effective  temperature 
(CET)  scale.  No  allowance,  however,  was  made  for 
the  different  rates  of  energy  expenditure.  The  scale  was 
compiled  only  for  men  either  seated  or  engaged  in  light 
activity. 

Figure  5  represents  the  corrected  effective  temperature 
nomogram.  The  CET  can  be  obtained  by  connecting 
the  appropriate  points  representing  the  dry  bulb  (or 
globe)  and  wet  bulb  temperatures  and  reading  the  CET 
value  at  the  intersection  of  this  line  with  the  relevant 
air  velocity  curve  from  the  family  of  curves  for  various 
air  velocities  running  diagonally  upwards  from  left  to 
right. 

The  effective  temperature  scale  may  be  considered  to 
be  reasonably  accurate  in  warm  climates  where  the  heat 
stress  is  not  high  but  it  may  be  misleading  at  high  levels 
of  heat  stress.  There  appears  to  be  an  inherent  error  in 
this  scale  if  used  as  an  index  of  physiological  strain, 
the  error  increasing  with  the  severity  of  the 
environmental  conditions.  For  low  and  moderate 
degrees  of  heat  stress,  the  effective  temperature  scales 


appear  to  assess  climatic  heat  stress  with  an  accuracy 
which  is  acceptable  for  most  practical  purposes. 

5.2.3. 1.2  Tropical  summer  index  (TSI) 

The  TSI  is  defined  as  the  temperature  of  calm  air, 
at  50  percent  relative  humidity  which  imparts  the  same 
thermal  sensation  as  the  given  environment.  The 
50  percent  level  of  relative  humidity  is  chosen  for  this 
index  as  it  is  a  reasonable  intermediate  value  for  the 
prevailing  humidity  conditions.  Mathematically,  TSI 
(°C)  is  expressed  as: 

TSI  =  0.745tg  +  0.308?w  -2.06Vv  + 0.841 

where 

Zw  =  wet  bulb  temperature,  in  °C; 
fg  =  globe  temperature,  in  °C;  and 
V  =  air  speed,  in  m/s. 

The  thermal  comfort  of  a  person  lies  between  TSI 
values  of  25°C  and  30°C  with  optimum  condition  at 
27.5°C.  Air  movement  is  necessary  in  hot  and  humid 
weather  for  body  cooling.  A  certain  minimum  desirable 
wind  speed  is  needed  for  achieving  thermal  comfort  at 
different  temperatures  and  relative  humidities.  Such 


0  5  10  15  20  25  30  35  40  45 

Wet  bulb  temperature  °C 

Fig.  5  Corrected  Effective  Temperature  Nomogram 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


37 


wind  speeds  are  given  in  Table  9.  These  are  applicable 
to  sedentary  work  in  offices  and  other  places  having 
no  noticeable  sources  of  heat  gain.  Where  somewhat 
wanner  conditions  are  prevalent,  such  as  in  godowns 
and  machine  shops  and  work  is  of  lighter  intensity,  and 
higher  temperatures  can  be  tolerated  without  much 
discomfort,  minimum  wind  speeds  for  just  acceptable 
warm  conditions  are  given  in  Table  10.  For  obtaining 
values  of  indoor  wind  speed  above  2.0  m/s,  mechanical 
means  of  ventilation  may  have  to  be  adopted  (see  also 
Part  8  ‘Building  Services,  Section  3  Air  Conditioning, 
Heating  and  Mechanical  Ventilation’  of  the  Code). 

The  warmth  of  the  environment  was  found  tolerable 
between  30°C  and  34°C  (TSI),  and  too  hot  above  this 
limit.  On  the  lower  side,  the  coolness  of  the  environment 
was  found  tolerable  between  19°C  and  25°C  (TSI)  and 
below  19°C  (TSI),  it  was  found  too  cold. 

Table  9  Desirable  Wind  Speeds  (m/s)  for 
Thermal  Comfort  Conditions 

(Clause  5.2. 3. 1.2) 

SI.  Dry  Bulb  Relative  Humidity 


No. 

Temperature 

Percent 

°C 

30 

40 

50 

60 

70 

80 

90 

(1) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

(9) 

i) 

28 

1) 

1) 

1) 

1) 

1) 

1) 

1) 

ii) 

29 

1) 

1) 

1) 

1) 

1) 

0.06 

0.19 

iii) 

30 

1) 

1) 

1) 

0.06 

0.24 

0.53 

0.85 

iv) 

31 

1) 

0.06 

0.24 

0.53 

1.04 

1.47 

2.10 

v) 

32 

0.20 

0.46 

0.94 

1.59 

2.26 

3.04 

2) 

vi) 

33 

0.77 

1.36 

2.12 

3.00 

2) 

2) 

2) 

vii) 

34 

1.85 

2.72 

2) 

2) 

2) 

2) 

2) 

viii) 

35 

3.20 

2) 

2) 

2) 

2) 

2) 

2) 

1(  None. 

2)  Higher  than  those  acceptable  in  practice. 


Table  10  Minimum  Wind  Speeds  (m/s)  for  Just 
Acceptable  Warm  Conditions 

(Clause  5.2. 3. 1.2) 


SI  Dry  Bulb 

No.  Temperatui 

°C 

(1)  (2) 

'e 

Relative  Humidity 

Percent 

30 

(3) 

40 

(4) 

50 

(5) 

60 

(6) 

70 

(7) 

80 

(8) 

90 

(9) 

i) 

28 

1) 

1) 

1) 

1) 

1) 

1) 

1) 

ii) 

29 

1) 

1) 

1) 

1) 

1) 

1) 

I) 

iii) 

30 

1) 

1) 

1) 

1) 

1) 

1) 

1) 

iv) 

31 

1) 

1) 

1) 

1) 

1) 

0.06 

0.23 

v) 

32 

1) 

1) 

1) 

0.09 

0.29 

0.60 

0.94 

vi) 

33 

1) 

0.04 

0.24 

0.60 

1.04 

1.85 

2.10 

vii) 

34 

0.15 

0.46 

0.94 

1.60 

2.26 

3.05 

2) 

viii) 

35 

0.68 

1.36 

2.10 

3.05 

2) 

2) 

2) 

ix) 

36 

1.72 

2.70 

2) 

2) 

2) 

2) 

2) 

"  None. 

2)  Higher  than  those  acceptable  in  practice. 


5.2.3. 1.3  Adaptive  thermal  comfort 

For  details  on  adaptive  thermal  comfort,  reference  shall 
be  made  to  Part  8  ‘Building  Services,  Section  3  Air 
Conditioning,  Heating  and  Mechanical  Ventilation’  of 
this  Code. 

5.2.3.2  There  will  be  a  limit  of  heat  tolerance  when  air 
temperatures  are  excessive  and  the  degree  of  physical 
activity  is  high.  This  limit  is  determined  when  the  bodily 
heat  balance  is  upset,  that  is,  when  the  bodily  heat  gain 
due  to  conduction,  convection  and  the  radiation  from 
the  surroundings  exceeds  the  bodily  heat  loss,  which  is 
mostly  by  evaporation  of  sweat  from  the  surface  of  the 
body.  The  limits  of  heat  tolerance  for  Indian  workers 
are  based  on  the  study  conducted  by  the  Chief  Adviser 
Factories,  Government  of  India,  Ministry  of  Labour 
and  are  given  in  his  report  on  Thermal  Stress  in  Textile 
Industry  (Report  No.  17)  issued  in  1956.  According  to 
this  Report,  where  workers  in  industrial  buildings 
wearing  light  clothing  are  expected  to  do  work  of 
moderate  severity  with  the  energy  expenditure  in  the 
range  273  to  284  W,  the  maximum  wet  bulb  temperature 
shall  not  exceed  29°C  and  adequate  air  movement 
subject  to  a  minimum  air  velocity  of  30  m/min  shall  be 
provided,  and  in  relation  to  the  dry  bulb  temperature, 
the  wet  bulb  temperature  of  air  in  the  work  room,  as 
far  as  practicable,  shall  not  exceed  that  given  in 
Table  11. 


Table  11  Maximum  Permissible  Wet  Bulb 
Temperatures  for  Given  Dry  Bulb  Temperatures 

(Clause  5. 2. 3. 2) 


SI 

Dry  Bulb 

Maximum  Wet-Bulb 

No. 

Temperature 

Temperature 

°c 

°c 

(1) 

(2) 

(3) 

i) 

30 

29.0 

ii) 

35 

28.5 

iii) 

40 

28.0 

iv) 

45 

27.5 

v) 

50 

27.0 

NOTES 

1  These  are  limits  beyond  which  the  industry  should  not  allow 
the  thermal  conditions  to  go  for  more  than  lh  continuously. 
The  limits  are  based  on  a  series  of  studies  conducted  on  Indian 
subjects  in  psychrometric  chamber  and  on  other  data  on  heat 
casualties  in  earlier  studies  conducted  in  Kolar  Gold  Fields  and 
elsewhere. 

2  Figures  given  in  this  table  are  not  intended  to  convey  that 
human  efficiency  at  50°C  will  remain  the  same  as  at  30°C, 
provided  appropriate  wet  bulb  temperatures  are  maintained. 
Efficiency  decreases  with  rise  in  the  dry  bulb  temperature  as 
well,  as  much  as  possible.  Long  exposures  to  temperature  of 
50°C  dry  bulb/27°C  wet  bulb  may  prove  dangerous. 

3  Refrigeration  or  some  other  method  of  cooling  is 
recommended  in  all  cases  where  conditions  would  be  worse 
than  those  shown  in  this  table. 


38 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


5.3  Methods  of  Ventilation 

General  ventilation  involves  providing  a  building  with 
relatively  large  quantities  of  outside  air  in  order  to 
improve  general  environment  of  the  building.  This  may 
be  achieved  in  one  of  the  following  ways: 

a)  Natural  supply  and  natural  exhaust  of  air; 

b)  Natural  supply  and  mechanical  exhaust  of  air; 

c)  Mechanical  supply  and  natural  exhaust  of  air; 
and 

d)  Mechanical  supply  and  mechanical  exhaust  of 
air. 

5.3.1  Control  of  Heat 

Although  it  is  recognized  that  general  ventilation  is  one 
of  the  most  effective  methods  of  improving  thermal 
environmental  conditions  in  factories,  in  many 
situations,  the  application  of  ventilation  should  be 
preceded  by  and  considered  along  with  some  of  the 
following  other  methods  of  control.  This  would 
facilitate  better  design  of  buildings  for  general 
ventilation,  either  natural  or  mechanical  or  both,  and 
also  reduce  their  cost. 

5.3. 1.1  Isolation 

Sometimes  it  is  possible  to  locate  heat  producing 
equipment,  such  as  furnaces  in  such  a  position  as  would 
expose  only  a  small  number  of  workers  to  hot 
environment.  As  far  as  practicable,  such  sources  of  heat 
in  factories  should  be  isolated. 

In  situations  where  relatively  few  people  are  exposed 
to  severe  heat  stress  and  their  activities  are  confined  to 
limited  areas  as  in  the  case  of  rolling  mill  operators 
and  crane  operators,  it  may  be  possible  to  enclose  the 
work  areas  and  provide  spot  cooling  or  supply 
conditioned  air  to  such  enclosures. 

5.3. 1.2  Insulation 

A  considerable  portion  of  heat  in  many  factories  is  due 
to  the  solar  radiation  falling  on  the  roof  surfaces,  which, 
in  turn,  radiate  heat  inside  the  building.  In  such 
situations,  insulations  of  the  roof  or  providing  a  false 
ceiling  or  double  roofing  would  be  very  effective  in 
controlling  heat.  Some  reduction  can  also  be  achieved 
by  painting  the  roof  in  heat  reflective  shades. 

Hot  surfaces  of  equipment,  such  as  pipes,  vessels,  etc, 
in  the  building  should  also  be  insulated  to  reduce  their 
surface  temperature. 

5.3. 1.3  Substitution 

Sometimes,  it  is  possible  to  substitute  a  hot  process  by 
a  method  that  involves  application  of  localized  or  more 
efficiently  controlled  method  of  heating.  Examples 
include  induction  hardening  instead  of  conventional 


heat  treatment,  cold  riveting  or  spot  welding  instead  of 
hot  riveting,  etc. 

5.3. 1.4  Radiant  shielding 

Hot  surfaces,  such  as  layers  of  molten  metal  emanate 
radiant  heat,  which  can  best  be  controlled  by  placing  a 
shield  having  a  highly  reflecting  surface  between  the 
source  of  heat  and  the  worker,  so  that  a  major  portion 
of  the  heat  falling  on  the  shield  is  reflected  back  to  the 
source.  Surfaces  such  as  of  tin  and  aluminium  have 
been  used  as  materials  for  shields.  The  efficiency  of 
the  shield  does  not  depend  on  its  thickness,  but  on  the 
reflectivity  and  emissivity  of  its  surface.  Care  should 
be  taken  to  see  that  the  shield  is  not  heated  up  by 
conduction  and  for  this  purpose  adequate  provision 
should  be  made  for  the  free  flow  upwards  of  the  heated 
air  between  the  hot  surface  and  the  shield  by  leaving 
the  necessary  air  space  and  providing  opening  at  the 
top  and  the  bottom  of  the  sides. 

5.3.2  Volume  of  Air  Required 

The  volume  of  air  required  shall  be  calculated  by  using 
both  the  sensible  heat  and  latent  heat  gain  as  the  bases. 
The  larger  of  the  two  values  obtained  should  be  used 
in  actual  practice. 

In  places  without  sufficient  wind  speeds  and/or  in 
buildings  where  effective  cross  ventilation  is  not 
possible  due  to  the  design  of  the  interior,  the  indoor  air 
may  be  exhausted  by  a  fan,  with  outdoor  air  entering 
the  building  through  the  open  windows. 

5.3.2. 1  Volume  of  air  required  for  removing  sensible 
heat 

When  the  amount  of  sensible  heat  given  off  by  different 
sources,  namely,  the  sun,  the  manufacturing  processes, 
machinery,  occupants  and  other  sources,  is  known  and 
a  suitable  value  for  the  allowable  temperature  rise  is 
assumed,  the  volume  of  outside  air  to  be  provided  for 
removing  the  sensible  heat  may  be  calculated  from: 

„  2.976  8  Ks 

e,- — 7 — 

where 

Qx  =  quantity  of  air,  in  m3/h; 

Ks  =  sensible  heat  gained,  in  W;  and 
t  =  allowable  temperature  rise,  in  °C. 

5.3.2. 2  Temperature  rise  refers  mainly  to  the  difference 
between  the  air  temperatures  at  the  outlet  (roof  exit) 
and  at  the  inlet  openings  for  outside  air.  As  very  little 
inlet  data  exist  on  allowable  temperature  rise  values 
for  supply  of  outside  air  in  summer  months,  the  values 
given  in  Table  12  related  to  industrial  buildings  may 
be  used  for  general  guidance. 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


39 


Table  12  Allowable  Temperature  Rise  Values 

0 Clause  5. 3.2. 2) 

SI  No.  Height  of  Outlet  Opening  Temperature  Rise 

m  °C 

(1) (2) (3) 

i)  6  3  to  4.5 

ii)  9  4.5  to  6.5 

iii)  12  6.5  to  11 

NOTES 

1  The  conditions  are  limited  to  light  or  medium  heavy 
manufacturing  processes,  freedom  from  radiant  heat  and  inlet 
openings  not  more  than  3  to  4.5  m  above  floor  level. 

2  At  the  working  zone  between  floor  level  and  1.5  m  above 
floor  level,  the  recommended  maximum  allowable  temperature 
rise  for  air  is  2°C  to  3°C  above  the  air  temperature  at  the  inlet 
openings. 


5.3. 2.3  Volume  of  air  required for  removing  latent  heat 

If  the  latent  heat  gained  from  the  manufacturing 
processes  and  occupants  is  also  known  and  a  suitable 
value  for  the  allowable  rise  in  the  vapour  pressure  is 
assumed: 

^  _  4  127.26^ 

e2~  i 

where 

Q2  =  quantity  of  air,  in  m3/h; 

Kx  =  latent  heat  gained,  in  W;  and 
h  =  allowable  vapour  pressure  difference  of 
mercury,  in  mm. 

NOTE  —  In  majority  of  the  cases,  the  sensible  heat  gain  will 
far  exceed  the  latent  heat  gain,  so  that  the  amount  of  outside 
air  to  be  drawn  by  ventilating  equipment  can  be  calculated  in 
most  cases  on  the  basis  of  the  equation  given  in  5.3. 2.1. 

5.3. 2.4  Ventilation  is  also  expressed  as  m3/h/m2  of  floor 
area.  This  relationship  fails  to  evaluate  the  actual  heat 
relief  provided  by  a  ventilation  system,  but  it  does  give 
a  relationship  which  is  independent  of  building  height. 
This  is  a  more  rational  approach,  because,  with  the  same 
internal  load,  the  same  amount  of  ventilation  air, 
properly  applied  to  the  work  zone  with  adequate 
velocity,  will  provide  the  desired  heat  relief  quite 
independently  of  the  ceiling  height  of  the  space,  with 
few  exceptions.  Ventilation  rates  of  30  to  60  m3/h/m2 
have  been  found  to  give  good  results  in  many  plants. 

5.4  Natural  Ventilation 

The  rate  of  ventilation  by  natural  means  through 
windows  or  other  openings  depends  on, 

a)  direction  and  velocity  of  wind  outside  and 
sizes  and  disposition  of  openings  (wind 
action);  and 

b)  convection  effects  arising  from  temperature 
of  vapour  pressure  difference  (or  both) 


between  inside  and  outside  the  room  and  the 
difference  of  height  between  the  outlet  and 
inlet  openings  (stack  effect). 

5.4.1  Ventilation  of  Non-Industrial  Buildings 

Ventilation  in  non-industrial  buildings  due  to  stack 
effect,  unless  there  is  a  significant  internal  load,  could 
be  neglected,  except  in  cold  regions,  and  wind  action 
may  be  assumed  to  be  predominant. 

5.4.1. 1  In  hot  dry  regions,  the  main  problem  in  summer 
is  to  provide  protection  from  sun’s  heat  so  as  to  keep 
the  indoor  temperature  lower  than  those  outside  under 
the  sun.  For  this  purpose  windows  and  other  openings 
are  generally  kept  closed  during  day  time  and  only 
minimum  ventilation  is  provided  for  the  control  of 
odours  or  for  removal  of  products  of  combustion. 

5.4. 1.2  In  warm  humid  regions,  the  problem  in  the 
design  of  non-industrial  buildings  is  to  provide  free 
passage  of  air  to  keep  the  indoor  temperature  as  near 
to  those  outside  in  the  shade  as  possible,  and  for  this 
purpose  the  buildings  are  oriented  to  face  the  direction 
of  prevailing  winds  and  windows  and  other  openings 
are  kept  open  on  both  windward  and  leeward  sides. 

5.4. 1.3  In  winter  months  in  cold  regions,  the  windows 
and  other  openings  are  generally  kept  shut,  particularly 
during  night;  and  ventilation  necessary  for  the  control 
of  odours  and  for  the  removal  of  products  of  combustion 
can  be  achieved  either  by  stack  action  or  by  some 
infiltration  of  outside  air  due  to  wind  action. 

5.4.2  Ventilation  of  Industrial  Buildings 

In  providing  natural  ventilation  of  all  industrial 
buildings  having  significant  internal  heat  loads  due  to 
manufacturing  process,  proper  consideration  should  be 
given  to  the  size  and  distribution  of  windows  and  other 
inlet  openings  in  relation  to  outlet  openings  so  as  to 
give,  with  due  regard  to  orientation,  prevailing  winds, 
size  and  configuration  of  the  building  and 
manufacturing  processes  carried  on,  maximum  possible 
control  of  thermal  environment. 

5.4.2. 1  In  the  case  of  industrial  buildings  wider  than 
30  m,  the  ventilation  through  windows  may  be 
augmented  by  roof  ventilation. 

5.4.3  Design  Guidelines  for  Natural  Ventilation 

5.4.3. 1  By  wind  action 

1)  A  building  need  not  necessarily  be  oriented 
perpendicular  to  the  prevailing  outdoor  wind; 
it  may  be  oriented  at  any  convenient  angle 
between  0°  and  30°  without  losing  any 
beneficial  aspect  of  the  breeze.  If  the 
prevailing  wind  is  from  East  or  West,  building 
may  be  oriented  at  45°  to  the  incident  wind  so 


40 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


as  to  diminish  the  solar  heat  without  much 
reduction  in  air  motion  indoors. 

2)  Inlet  openings  in  the  buildings  should  be  well 
distributed  and  should  be  located  on  the 
windward  side  at  a  low  level,  and  outlet 
openings  should  be  located  on  the  leeward 
side.  Inlet  and  outlet  openings  at  high  levels 
may  only  clear  the  top  air  at  that  level  without 
producing  air  movement  at  the  level  of 
occupancy. 

3)  Maximum  air  movement  at  a  particular  plane 
is  achieved  by  keeping  the  sill  height  of  the 
opening  at  85  percent  of  the  critical  height 
(such  as  head  level)  for  the  following 
recommended  levels  of  occupancy: 

a)  For  sitting  on  chair  0.75  m, 

b)  For  sitting  on  bed  0.60  m,  and 

c)  For  sitting  on  floor  0.40  m. 

4)  Inlet  openings  should  not  as  far  as  possible 
be  obstructed  by  adjoining  buildings,  trees, 
sign  boards  or  other  obstructions  or  by 
partitions  inside  in  the  path  of  air  flow. 

5)  In  rooms  of  normal  size  having  identical 
windows  on  opposite  walls  the  average  indoor 
air  speed  increases  rapidly  by  increasing  the 
width  of  window  up  to  two-third  of  the  wall 
width;  beyond  that  the  increase  is  in  much 
smaller  proportion  than  the  increase  of  the 
window  width.  The  air  motion  in  the  working 
zone  is  maximum  when  window  height  is 
1.1m.  Further  increase  in  window  height 
promotes  air  motion  at  higher  level  of  window, 
but  does  not  contribute  additional  benefits  as 
regards  air  motion  in  the  occupancy  zones  in 
buildings. 

6)  Greatest  flow  per  unit  area  of  openings  is 
obtained  by  using  inlet  and  outlet  openings  of 
nearby  equal  areas  at  the  same  level. 


50 


Fig.  6  Effect  of  Area  of  Opening  on  Average 
Indoor  Wind  Velocity 


7)  For  a  total  area  of  openings  (inlet  and  outlet) 
of  20  percent  to  30  percent  of  floor  area,  the 
average  indoor  wind  velocity  is  around 
30  percent  of  outdoor  velocity.  Further 
increase  in  window  size  increases  the  available 
velocity  but  not  in  the  same  proportion  as 
shown  in  Fig.  6.  In  fact,  even  under  most 
favourable  conditions  the  maximum  average 
indoor  wind  speed  does  not  exceed  40  percent 
of  outdoor  velocity. 

8)  Where  the  direction  of  wind  is  quite  constant 
and  dependable,  the  size  of  the  inlet  should 
be  kept  within  30  to  50  percent  of  the  total 
area  of  openings  and  the  building  should  be 
oriented  perpendicular  to  the  incident  wind. 
Where  direction  of  the  wind  is  quite  variable 
the  openings  may  be  arranged  so  that  as  far  as 
possible  there  is  approximately  equal  area  on 
all  sides.  Thus  no  matter  what  the  wind 
direction  be,  there  would  be  some  openings 
directly  exposed  to  wind  pressure  and  others 
to  air  suction  and  effective  air  movement 
through  the  building  would  be  assured. 

9)  Windows  of  living  rooms  should  open  directly 
to  an  open  space.  In  places  where  building 
sites  are  restricted,  open  space  may  have  to 
be  created  in  the  buildings  by  providing 
adequate  courtyards. 

10)  In  the  case  of  rooms  with  only  one  wall 
exposed  to  outside,  provision  of  two  windows 
on  that  wall  is  preferred  to  that  of  a  single 
window. 

1 1 )  Windows  located  diagonally  opposite  to  each 
other  with  the  windward  window  near  the 
upstream  comer  give  better  performance  than 
other  window  arrangements  for  most  of  the 
building  orientations. 

12)  Horizontal  louvers,  that  is,  sunshades  atop 
windows  deflect  the  incident  wind  upward  and 
reduce  air  motion  in  the  zone  of  occupancy.  A 
horizontal  slot  between  the  wall  and  horizontal 
louver  prevents  upward  deflection  of  air  in  the 
interior  of  rooms.  Provision  of  inverted  L  type 
(F)  louver  increases  the  room  air  motion 
provided  that  the  vertical  projection  does  not 
obstruct  the  incident  wind  ( see  Fig.  7). 

13)  Provision  of  horizontal  sashes  inclined  at  an 
angle  of  45°  in  appropriate  direction  helps  to 
promote  the  indoor  air  motion.  Sashes 
projecting  outward  are  more  effective  than 
projecting  inward. 

14)  Air  motion  at  working  plane  0.4  m  above  the 
floor  can  be  enhanced  by  30  percent  using  a 
pelmet  type  wind  deflector  ( see  Fig.  8). 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


41 


Fig.  7  L-Type  Louver 

15)  Roof  overhangs  help  promoting  air  motion  in 
the  working  zone  inside  buildings. 

1 6)  In  case  of  room  with  windows  on  one  wall, 
with  single  window,  the  room  wind  velocity 
inside  the  room  on  the  windward  side  is 
1 0  percent  of  outdoor  velocity  at  points  up  to 
a  distance  of  one-sixth  of  room  width  from  the 
window  and  then  decreases  rapidly  and  hardly 
any  air  movement  is  produced  in  the  leeward 
half  portion  of  the  room.  The  average  indoor 
wind  velocity  is  generally  less  than  1 0  percent 
of  outdoor  velocity.  When  two  windows  are 
provided  and  wind  impinges  obliquely  on 
them,  the  inside  velocity  increases  up  to 
1 5  percent  of  the  outdoor  velocity. 


1 7)  Cross  ventilation  can  be  obtained  through  one 
side  of  the  building  to  the  other,  in  case  of 
narrow  buildings  with  the  width  common  in 
the  multistoreyed  type  by  the  provision  of 
large  and  suitably  placed  windows  or 
combination  of  windows  and  wall  ventilators 
for  the  inflow  and  outflow  of  air. 

18)  Verandah  open  on  three  sides  is  to  be  preferred 
since  it  causes  an  increase  in  the  room  air 
motion  for  most  of  the  orientations  of  the 
building  with  respect  to  the  outdoor  wind. 

19)  A  partition  placed  parallel  to  the  incident  wind 
has  little  influence  on  the  pattern  of  the  air 
flow,  but  when  located  perpendicular  to  the 
main  flow,  the  same  partition  creates  a  wind 
shadow.  Provision  of  a  partition  with  spacing 
of  0.3  m  underneath  helps  augmenting  air 
motion  near  floor  level  in  the  leeward 
compartment  of  wide  span  buildings. 

20)  Air  motion  in  a  building  unit  having  windows 
tangential  to  the  incident  wind  is  accelerated 
when  another  unit  is  located  at  end-on  position 
on  downstream  side  (see  Fig.  9). 

2 1 )  Air  motion  in  two  wings  oriented  parallel  to 
the  prevailing  breeze  is  promoted  by  connecting 
them  with  a  block  on  downstream  side. 


f[ 

H  w 

Bli  ^  ° 

H  □  “  H  w  /  4 

i 

WD  =  H  w / 6 

1 

X 

* 


Hw-  WINDOW  HEIGHT 
Hd  -  DEFLECTOR  HEIGHT 
WD  -  DEFLECTOR  WIDTH 


Fig.  8  Sketch  of  a  Pelmet  Type  Wind  Deflector 


42 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


22)  Air  motion  in  a  building  is  not  affected  by 
constructing  another  building  of  equal  or 
smaller  height  on  the  leeward  side;  but  it  is 
slightly  reduced  if  the  leeward  building  is 
taller  than  the  windward  block. 

23)  Air  motion  in  a  shielded  building  is  less  than 
that  in  an  unobstructed  building.  To  minimise 
shielding  effect,  the  distances  between  two 
rows  should  be  8  H  for  semi-detached  houses 
and  10  //for  long  rows  houses.  However,  for 
smaller  spacing  the  shielding  effect  is  also 
diminished  by  raising  the  height  of  the 
shielded  building. 

24)  Hedges  and  shrubs  defect  the  air  away  from 
the  inlet  openings  and  cause  a  reduction  in 
indoor  air  motion.  These  elements  should  not 
be  planted  at  a  distance  of  about  8  m  from  the 
building  because  the  induced  air  motion  is 
reduced  to  minimum  in  that  case.  However, 
air  motion  in  the  leeward  part  of  the  building 
can  be  enhanced  by  planting  a  low  hedge  at  a 
distance  of  2  m  from  the  building. 

25)  Trees  with  large  foliage  mass  having  trunk 
bare  of  branches  up  to  the  top  level  of  window, 
deflect  the  outdoor  wind  downwards  and 
promotes  air  motion  in  the  leeward  portion  of 
buildings, 

26)  Ventilation  conditions  indoors  can  be 
ameliorated  by  constructing  buildings  on  earth 


mound  having  a  slant  surface  with  a  slope  of 
10°  on  upstream  side. 

27)  In  case  of  industrial  buildings  the  window 
height  should  be  about  1.6  m  and  width  about 
two-third  of  wall  width.  These  should  be 
located  at  a  height  of  1 . 1  m  above  the  floor. 
In  addition  to  this,  openings  around  0.9  m  high 
should  be  provided  over  two-third  length  of 
the  glazed  area  in  the  roof  lights. 

28)  Height  of  industrial  buildings,  although 
determined  by  the  requirements  of  industrial 
processes  involved,  generally  kept  large 
enough  to  protect  the  workers  against  hot 
stagnant  air  below  the  ceiling  as  also  to  dilute 
the  concentration  of  contaminant  inside. 
However,  if  high  level  openings  in  roof  or 
walls  are  provided,  building  height  can  be 
reduced  to  4  m  without  in  any  way  impairing 
the  ventilation  performance. 

29)  The  maximum  width  up  to  which  buildings  of 
height  usually  found  in  factories,  being 
effectively  ventilated  by  natural  means  by 
wind  action,  is  30  m,  beyond  which  sufficient 
reliance  cannot  be  placed  on  prevailing  winds. 
Approximately  half  the  ventilating  area  of 
openings  should  be  between  floor  level  and  a 
height  of  2.25  m  from  the  floor. 

NOTE  —  For  data  on  outdoor  wind  speeds  at  a  place,  reference 

may  be  made  to  ‘The  Climatic  Data  Handbook’  prepared  by 

Central  Building  Research  Institute,  Roorkee,  1999’. 

5.4.3.2  By  stack  effect 

Natural  ventilation  by  stack  effect  occurs  when  air 
inside  a  building  is  at  a  different  temperature  than  air 
outside.  Thus  in  heated  buildings  or  in  buildings 
wherein  hot  processes  are  carried  on  and  in  ordinary 
buildings  during  summer  nights  and  during  pre¬ 
monsoon  periods,  the  inside  temperature  is  higher  than 
that  of  outside,  cool  outside  air  will  tend  to  enter  through 
openings  at  low  level  and  warm  air  will  tend  to  leave 
through  openings  at  high  level.  It  would,  therefore,  be 
advantageous  to  provide  ventilators  as  close  to  ceilings 
as  possible.  Ventilators  can  also  be  provided  in  roofs 
as,  for  example,  cowl,  vent  pipe,  covered  roof  and  ridge 
vent. 

5.5  Mechanical  Ventilation 

The  requirements  of  mechanical  ventilation  shall  be  in 
accordance  with  Part  8  ‘Building  Services,  Section  3 
Air  Conditioning,  Heating  and  Mechanical  Ventilation’ 
of  the  Code. 

5.6  Determining  Rate  of  Ventilation 
5.6.1  Natural  Ventilation 

This  is  difficult  to  measure  as  it  varies  from  time  to 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


43 


time.  The  amount  of  outside  air  through  windows  and 
other  openings  depends  on  the  direction  and  velocity 
of  wind  outside  (wind  action)  and/or  convection  effects 
arising  from  temperature  or  vapour  pressure  differences 
(or  both)  between  inside  and  outside  of  the  building 
(stack  effect). 

5.6. 1.1  Wind  action 

For  determining  the  rate  of  ventilation  based  on  wind 
action  the  wind  may  be  assumed  to  come  from  any 
direction  within  45°  of  the  direction  of  prevailing  wind. 
Ventilation  due  to  external  wind  is  given  by  the 
following  formula: 

Qv  =  K.A.V 


resulting  air  flow  is  not  equal  to  the  two  flows  estimated 
separately. 

When  acting  simultaneously,  the  rate  of  air  flow  through 
the  building  may  be  computed  by  the  following 
equation: 

02=0w2+a2 

where 

Q  =  resultant  volume  of  air  flow,  in  m3/min; 

Qw  =  volume  of  air  flow  due  to  wind  force,  in  m3/ 
min;  and 

Qt  =  volume  of  air  flow  due  to  thermal  force,  in 
m3/min. 


where 

Qw  =  rate  of  air  flow,  in  m3/h; 

K  =  coefficient  of  effectiveness,  which  may  be 
taken  as  0.6  for  wind  perpendicular  to 
openings  and  0.3  for  wind  at  an  angle  less 
than  45°  to  the  openings; 

A  =  free  area  of  inlet  openings,  in  m2;  and 
V  =  wind  speed,  in  m/h. 

NOTE  —  For  wind  data  at  a  place,  the  local  Meteorological 
Department  may  be  consulted. 

5.6.1.2  Stack  effect  (thermal  action) 

Ventilation  due  to  convection  effects  arising  from 
temperature  difference  between  inside  and  outside  is 
given  by: 

Qt  =  7-°  A  y\h  (?r~0 

where 

QT  =  rate  of  air  flow,  in  m3/h; 

A  =  free  area  of  inlet  openings,  in  m2; 
h  =  vertical  distance  between  inlets  and  outlets, 
in  m; 

t,  =  average  temperature  of  indoor  air  at  height 
h,  in  °C;  and 

ta  =  temperature  of  outdoor  air,  in  °C. 

NOTE  —  The  equation  is  based  on  0.65  times  the  effectiveness 
of  openings.  This  should  be  reduced  to  0.50,  if  conditions  are 
not  favourable. 


5.6.1.3  When  areas  of  inlet  and  outlet  openings  are 
unequal,  the  value  of  A  may  be  calculated  using  the 
equation: 


2 

A* 


^inlct  ^outlet 


5.6. 1.4  Combined  Effect  of  Wind  and  Thermal  Action 

When  both  forces  (wind  and  thermal)  act  together  in 
the  same  direction,  even  without  interference,  the 


Wind  velocity  and  direction,  outdoor  temperature,  and 
indoor  distribution  cannot  be  predicted  with  certainty, 
and  refinement  in  calculation  is  not  justified.  A  simple 
method  is  to  calculate  the  sum  of  the  flows  produced 
by  each  force  separately.  Then  using  the  ratio  of  the 
flow  produced  by  thermal  forces  to  the  aforementioned 
sum,  the  actual  flow  due  to  the  combined  forces  can  be 
approximated  from  Fig.  10.  When  the  two  flows  are 
equal,  the  actual  flow  is  about  30  percent  greater  than 
the  flow  caused  by  either  force  acting  independently 
(see  Fig.  10). 


5  ui 

LL  LU 
Ll  O' 

ocu 

LLl  £ 
CL  D 
H  LU 

2  & 
LLl 

5  % 
o  ^ 

_l  LU 


i—  w 

o  2 


0  20  40  60  80  100 


FLOW  DUE  TO  TEMPERATURE 
DIFFERENCE  AS  PERCENT  OF  TOTAL 


Fig.  10  Determination  of  Flow  Caused  by 
Combined  Forces  of  Wind  and  Temperature 
Difference 


Judgment  is  necessary  for  proper  location  of  openings 
in  a  building  specially  in  the  roof,  where  heat,  smoke 
and  fumes  are  to  be  removed.  Usually,  windward 


44 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


monitor  openings  should  be  closed,  but  if  wind  is  so 
slight  that  temperature  head  can  overcome  it,  all 
openings  may  be  opened. 

5. 6. 1.5  For  method  for  determining  the  rate  of 
ventilation  based  on  probable  indoor  wind  speed  with 
typical  illustrative  example  for  residential  building, 
reference  may  be  made  to  A-4  of  good  practice  [9-1(6)]. 

5.6.2  Mechanical  Ventilation 

The  determination  of  rate  of  ventilation  in  case  of 
mechanical  ventilation  shall  be  done  in  accordance  with 
Part  8  ‘Building  Services,  Section  3  Air  Conditioning, 
Heating  and  Mechanical  Ventilation’  of  the  Code. 

5.6.3  Combined  effect  of  Different  Methods  of 
Ventilation 

When  combination  of  two  or  more  methods  of  general 
ventilation  is  used,  the  total  rate  of  ventilation  shall  be 
reckoned  as  the  highest  of  the  following  three,  and  this 
rule  shall  be  followed  until  an  exact  formula  is 
established  by  research: 

a)  1 .25  times  the  rate  of  natural  ventilation, 

b)  Rate  of  positive  ventilation,  and 

c)  Rate  of  exhaust  of  air. 

5.6.4  Measurement  of  Air  Movement 

The  rate  of  air  movement  of  turbulent  type  at  the 
working  zone  shall  be  measured  either  with  a  Kata 
thermometer  (dry  silvered  type)  or  heated  thermometer 
or  properly  calibrated  thermocouple  anemometer. 
Whereas  anemometer  gives  the  air  velocity  directly, 
the  Kata  thermometer  and  heated  thermometer  give 
cooling  power  of  air  and  the  rate  of  air  movement  is 
found  by  reference  to  a  suitable  nomogram  using  the 
ambient  temperature. 


5.7  Energy  Conservation  in  Ventilation  System 

5.7.1  Maximum  possible  use  should  be  made  of  wind 
induced  natural  ventilation.  This  may  be  accomplished 
by  following  the  design  guidelines  given  in  5.7.1. 1. 

5.7.1. 1  Adequate  number  of  circulating  fans  should  be 
installed  to  serve  all  interior  working  areas  during  summer 
months  in  the  hot  dry  and  warm  humid  regions  to  provide 
necessary  air  movement  at  times  when  ventilation  due  to 
wind  action  alone  does  not  afford  sufficient  relief. 

5.7.1. 1.1  The  capacity  of  a  ceiling  fan  to  meet  the 
requirement  of  a  room  with  the  longer  dimension  D 
metre  should  be  about  55 D  m3/min. 

5. 7. 1.1. 2  The  height  of  fan  blades  above  the  floor 
should  be  (3 H  +  W)/ 4,  where  H  is  the  height  of  the 
room,  and  W  is  the  height  of  work  plane. 

5.7. 1.1. 3  The  minimum  distance  between  fan  blades 
and  the  ceiling  should  be  about  0.3  m. 

5.7.2  Electronic  regulators  should  be  used  instead  of 
resistance  type  regulators  for  controlling  the  speed  of 
fans. 

5.7.3  When  actual  ventilated  zone  does  not  cover  the 
entire  room  area,  then  optimum  size  of  ceiling  fan 
should  be  chosen  based  on  the  actual  usable  area  of 
room,  rather  than  the  total  floor  area  of  the  room.  Thus 
smaller  size  of  fan  can  be  employed  and  energy  saving 
could  be  achieved. 

5.7.4  Power  consumption  by  larger  fans  is  obviously 
higher,  but  their  power  consumption  per  square  metre 
of  floor  area  is  less  and  service  value  higher.  Evidently, 
improper  use  of  fans  irrespective  of  the  rooms’ 
dimensions  is  likely  to  result  in  higher  power 
consumption.  From  the  point  of  view  of  energy 
consumption,  the  number  of  fans  and  the  optimum  sizes 
for  rooms  of  different  dimensions  are  given  in  Table  1 3 . 


Table  13  Optimum  Size/Number  of  Fans  for  Rooms  of  Different  Sizes 

( Clause  5.7.4) 


SI  Room  Optimum  Size,  mm/Number  of  Fans 

No.  Width  for  Room  Length 


m 


(1) 

(2) 

4  m 

(?) 

5  m 
(4) 

6  m 

(5) 

7m 

(6) 

8  m 

(7) 

9m 

(8) 

10  m 

(9) 

1 1  m 
(10) 

12  m 

(in 

14  m 
(12) 

16  m 
(13) 

1) 

3 

1  200/1 

1  400/1 

1  500/1 

1  050/2 

1  200/2 

1  400/2 

1  400/2 

1  400/2 

1  200/3 

1  400/3 

1  400/3 

il) 

4 

1  200/1 

1  400/1 

1  200/2 

1  200/2 

1  200/2 

1  400/2 

1  400/2 

1  500/2 

1  200/3 

1  400/3 

1  500/3 

111) 

5 

1  400/1 

1  400/1 

1  400/2 

1  400/2 

1  400/2 

1  400/2 

1  400/2 

1  500/2 

1  400/3 

1  400/3 

1  500/3 

iv) 

6 

1  200/2 

1  400/2 

900/4 

1  050/4 

1  200/4 

1  400/4 

1  400/4 

1  500/4 

1  200/6 

1  400/6 

1  500/6 

V) 

7 

1  200/2 

1  400/2 

1  050/4 

1  050/4 

1  200/4 

1  400/4 

1  400/4 

1  500/4 

1  200/6 

1  400/6 

1  500/6 

VI) 

8 

1  200/2 

1  400/2 

1  200/4 

1  200/4 

1  200/4 

1  400/4 

1  400/4 

1  500/4 

1  200/6 

1  400/6 

1  500/6 

vii) 

9 

1  400/2 

1  400/2 

1  400/4 

1  400/4 

1  400/4 

1  400/4 

1  400/4 

1  500/4 

1  400/6 

1  400/6 

1  500/6 

viii) 

10 

1  400/2 

1  400/2 

1  400/4 

1  400/4 

1  400/4 

1  400/4 

1  400/4 

1  500/4 

1  400/6 

1  400/6 

1  500/6 

IX) 

11 

1  500/2 

1  500/2 

1  500/4 

1  500/4 

1  500/4 

1  500/4 

1  500/4 

1  500/4 

1  500/6 

1  500/6 

1  500/6 

X) 

12 

1  200/3 

1  400/3 

1  200/6 

1  200/6 

1  200/6 

1  400/6 

1  400/6 

1  500/6 

1  200/7 

1  400/9 

1  400/9 

XI) 

13 

1  400/3 

1  400/3 

1  200/6 

1  200/6 

1  200/6 

1  400/6 

1  400/6 

1  500/6 

1  400/9 

1  400/9 

1  500/9 

xii) 

14 

1  400/3 

1  400/3 

1  400/6 

1  400/6 

1  400/6 

1  400/6 

1  400/6 

1  500/6 

1  400/9 

1  400/9 

1  500/9 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


45 


ANNEX A 
(< Clause  3.4.1) 

METHOD  OF  CALCULATING  SOLAR  LOAD  ON  VERTICAL 
SURFACES  OF  DIFFERENT  ORIENTATION 


A-l  DETAILS  OF  CALCULATION 

A-l.l  The  solar  energy  above  the  earth’s  atmosphere 
is  constant  and  the  amount  incident  on  unit  area  normal 
to  sun’s  rays  is  called  solar  constant  (1.360  8  kWm'2 
or  2  cal/cm2/min).  This  energy,  in  reaching  the  earth’s 
surface,  is  depleted  in,  the  atmosphere  due  to  scattering 
by  air  molecules,  water  vapour,  dust  particles,  and 
absorption  by  water  vapour  and  ozone.  The  depletion 
varies  with  varying  atmospheric  conditions.  Another 
important  cause  of  depletion  is  the  length  of  path 
traversed  by  sun’s  rays  through  the  atmosphere.  This 
path  is  the  shortest  when  sun  is  at  the  zenith  and,  as  the 
altitude  of  the  sun  decreases,  the  length  of  path  in  the 
atmosphere  increases.  Figure  11  gives  the  computed 
incident  solar  energy/hour  on  unit  surface  area  normal 
to  the  rays  under  standard  atmospheric  conditions  ( see 
Note  below)  for  different  altitudes  of  the  sun. 

NOTE  —  The  standard  atmospheric  conditions  assumed  for 
this  computation  are:  cloud-free,  300  dust  particles  per  cm3, 
15  mm  of  precipitable  water,  2.5  mm  of  ozone,  at  sea  level. 

A-1.2  In  order  to  calculate  the  solar  energy  on  any 
surface  other  than  normal  to  the  rays,  the  altitude  of 
the  sun  at  that  time  should  be  known.  The  corresponding 
value  of  direct  solar  radiation  (/N)  should  then  be  found 
with  the  help  of  Fig.  12.  The  solar  radiation  incident 
on  any  surface  (7S)  is  given  by: 

h  =  4n  (sin  (3  sin  §  +  cos  P  cos  a  cos 

where 

p  =  solar  altitude, 

(])  =  angle  tilt  of  the  surface  from  the  vertical 

( see  Fig.  12),  and 
a  =  wall  solar  azimuth  angle. 

A-2  EXAMPLE  TO  FIND  OUT  ORIENTATION 
ON  THE  BASIS  OF  SOLAR  LOAD 

A-2.1  Example 

A-2. 1.1  As  an  example,  a  simple  building  with  flat 
roof,  10  m  x  20  m,  and  4  m  high  is  dealt  with  below. 
For  the  sake  of  generalization,  no  shading  device  or 
verandah  is  taken. 

A-2.1.2  As  the  roof  is  horizontal,  it  will  receive  the 
same  solar  heat  in  any  orientation. 

A-2.1.3  The  area  of  the  vertical  surfaces  are  4  m  x 
1 0  m  =  A  (say)  and  4  m  x  20  m  =  2 A.  Since,  the  external 
wall  surface  are  not  in  shade  except  when  the  sun  is 


0  10  20  30  40  50  60  70  80  90 

SOLAR  ALTITUDE-DEGREES 


Fig.  1 1  Direct  Solar  Intensities  Normal  to  Sun  at 
Sea  Level  for  Standard  Condition  (Computed) 


Fig.  12  Definition  of  Solar  Angles 


not  shining  on  them,  the  total  solar  load  in  a  day  on  a 
surface  can  be  obtained  by  multiplying  the  total  load 
per  unit  area  per  day  ( see  Table  3)  by  the  area  of  the 
surface.  For  four  principal  orientations  of  the  building, 
the  total  solar  load  on  the  building  is  worked  out  in 
Table  14. 

A-2. 1.4  From  Table  14,  it  can  be  seen  that  for  the  above 
type  of  building,  orientation  3  (longer  surface  facing 
North  and  South)  is  appropriate  as  it  affords  maximum 
solar  heat  gain  in  winter  and  in  summer.  This  is  true  for 
all  places  of  India  from  the  point  of  solar  heat  gain.  By 
further  increasing  the  length  to  breadth  ratio,  the 


46 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  14  Solar  Heat  Gained  Due  to  Orientation  of  Buildings 

( Clause  A-2.1 .3) 


8°  N  THIRUVANANTHAPURAM 

1 3°  N  CHENNAI 

May  16 

Dec  22 

May  16 

Dec  22 

1. 

North 

2  177  x  A  =  2  177A 

— 

1  625  x  A  =  1  625A 

— 

East 

2  618  x  2A  =  5  236A 

2  177  x  2A  =  4  354A 

2  697  x  2A  =  5  394A 

2  019  x  2A  =  4  038A 

South 

— 

4  164  x  A  =  4  164A 

— 

4  385  x  A  =  4  385A 

West 

2  618  x  2A  =  5  236A 

2  177  x  2A  =  4  354A 

2  697  x  2A  =  5  394A 

2  019  x  2A  =  4  038A 

Total 

12  649 A 

12  872A 

12413A 

12  461A 

2. 

NE 

2  650  x  A  =  2  650A 

410  x  A  =  410A 

2  492  x  A  =  2  492A 

315  x  A  =  315A 

SE 

1  167  x  2A  =  2  334A 

3  391  x  2A  =  6  782A 

1  341  x  2A  =  2  682A 

3  423  x  2A  =  6  846A 

SW 

1  167  x  2A  =  2  334A 

3  391  x  a  =  3  391A 

1  341  x  A=  1  341A 

3  423  x  A  =  3  423A 

NW 

2  650  x  2A  =  5  300A 

410  x  2A  =  820A 

2  492  x  A  =  4  984A 

315  x  2A  =  630A 

Total 

12  618A 

1 1  403A 

1 1  499A 

11  214A 

3. 

North 

2  177  x  2A  =  4  354A 

— 

1  625  x  2A  =  3  2 50 A 

— 

East 

2  618  x  A  =  2  618A 

2  177  x  A  =  2  177A 

2  697  x  A  =  2  697A 

2  019  x  A  =  2  019A 

South 

— 

4  164  x  2A  =  8  328A 

— 

4  385  x  2A  =  8  770A 

West 

2  618  x  A  =  2  618A 

2  177  x  A  =  2  177A 

2  697  x  A  =  2  697A 

2  019  x  A  =  2  019A 

Total 

9  590A 

12  602A 

8  644A 

12  808A 

4. 

NE 

2  650  x  2A  =  5  300A 

— 

2  492  x  A  =  4  984A 

315  x  2A  =  630A 

SE 

1  167  x  A=  1  167A 

2  177  x  A  =  2  177A 

1  341  x  A=  1  341A 

3  423  x  A  =  3  423A 

SW 

1  167  x  2A  =  2  334A 

4  164  x  2A  =  8  328A 

1  341  x  2A  =  2  682A 

3  423  x  2A  =  6  846A 

NW 

2  650  x  A  =  2  650A 

2  177  x  A  =  2  177A 

2  492  x  A  =  2  492A 

315  x  A  =  315A 

Total 

11  451A 

12  6  82 A 

1 1  499A 

11  214A 

19°  N  MUMBAI 

23°  N  KOLKATA 

May  16 

Dec  22 

May  16 

Dec  22 

1. 

North 

962  x  A  =  962A 

— 

741  x  A  =  741A 

— 

East 

2  795  x  2A=  5  590A 

1  830  x  2A  =  3  660A 

2  871  x  2A  =  5  742A 

1  703  x  2A  =  3  406A 

South 

— 

4  574  x  A  =  4  574A 

205  x  A  =  205A 

4  637  x  A  =  4  637A 

West 

2  795  x  2A  =  5  590A 

1  830  x  2A  =  3  660A 

2  871  x  2A  =  5  742A 

1  703  x  2A  =  3  406A 

Total 

12  142  A 

1 1  8 94 A 

12  430A 

1 1  449A 

2. 

NE 

2  255  x  A  =  2  255A 

237  x  A  =  237A 

2  192  x  A  =  2  192A 

173  x  A  =  173A 

SE 

1  640  x  2A  =  3  280A 

3  438  x  2A  =  6  876A 

1  845  x  2A  =  3  690A 

3  454  x  2A  =  6  908A 

SW 

1  640  x  A  =  1  640A 

3  438  x  A  =  3  438A 

1  845  x  A  =  1  845A 

3  454  x  A  =  3  454A 

NW 

2  255  x  2A  —  4  510A 

237  x  2A  =  474A 

2  192  x  2A  =  4  384A 

173  x  2A  =  346A 

Total 

11  685A 

1 1  025A 

12  111A 

10  881A 

3. 

North 

962  x  2A  =  1  924A 

— 

741  x  2A=  1  482A 

— 

East 

2  795  x  A  =  2  795A 

1  830  x  A  =  1  830A 

2  871  x  A  =  2  871A 

1  703  x  A  =  1  703A 

South 

— 

4  574  x  2A  =  9  148A 

205  x  2A  =  410A 

4  637  x  2A  =  9  274A 

West 

2  795  x  A  =  2  795A 

1  830  x  A  =  1  830A 

2  871  x  A  =  2  871A 

1  703  x  A  =  1  703A 

Total 

7  514A 

12  808A 

7  634A 

12  680A 

4. 

NE 

2  255  x  2A  =  4  510A 

237  x  2A  =  474A 

2  192  x  2A  =  4  384A 

173  x  2A  =  346A 

SE 

1  640  x  A  =  1  640A 

3  438  x  A  =  3  438A 

1  845  x  A  =  1  845A 

3  454  x  A  =  3  454A 

SW 

1  640  x  2A  =  3  280A 

3  438  x  2A  =  6  876A 

1  845  x  2A  =  3  690A 

3  454  x  2A  =  6  908A 

NW 

2  255  x  A  =  2  255A 

237  x  A  =  237A 

2  192  x  A  =  2  192A 

173  x  A  =  173A 

Total 

11  685A 

1 1  025A 

12  111A 

10  881A 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


47 


Table  14  —  {Concluded) 


29°  N  DELHI 


May  16 

Dec  22 

1 .  North 

536  x  A  =  536A 

— 

East 

2  950  x  2A  =  5  900A 

1  467  x  2A  =  2  934A 

South 

741  x  A  =  741A 

4  543  x  A  =  4  543A 

West 

2  950  x  2A  =  5  9 00 A 

1  467  x  2A  =  2  934A 

Total 

13  077A 

10  41 1A 

2.  NE 

2  098  x  A  =  2  098A 

1 10  x  A  =  1 10A 

SE 

2  192  x  2A  =  4  384A 

3  265  x  2A  =  6  530A 

sw 

2  192  x  A  =  2  192A 

3  265  x  A  =  3  265A 

NW 

2  098  x2A  =  4  196A 

1 10  x  2A  =  220A 

Total 

12  870A 

10  125A 

3.  North 

536  x  2A  =  1  072A 

— 

East 

2  950  x  A  =  2  950A 

1  467  x  A  =  1  467 A 

South 

741  x  2A=  1  482A 

4  543  x  2A  =  9  086A 

West 

2  950  x  A  =  2  950A 

1  467  x  A  =  1  467 A 

Total 

8  454A 

12  020A 

4.  NE 

2  098  x2A  =  4  196A 

1 10  x  2A  =  220A 

SE 

2  1 92  x  A  =  2  192A 

3  265  x  A  =  3  265A 

SW 

2  192  x  2A  =  4  3  84A 

3  265  x2A  =  6  530A 

NW 

2  098  xA  =  4  196A 

110xA=110A 

Total 

12  870A 

10  125  A 

A 


2A 


2A 


A 

TYPE  I 


TYPE  II 


TYPE  IV 


advantage  of  this  orientation  will  be  more  pronounced. 
It  may  also  be  noted  that  in  higher  altitudes,  the  relative 
merit  of  this  orientation  is  more. 

A-2.1.5  It  is  also  seen  that  the  total  solar  heat  on  the 
building  is  the  same  for  orientation  2  and  4.  But  if  the 
site  considerations  require  a  choice  between  these  two, 
orientation  2  should  be  preferred  at  places  north  of 
latitude  23°N  and  orientation  4  at  southern  places.  This 
is  so  because  the  total  solar  load  per  unit  area  in  summer 
on  the  north  western  wall  decreases  with  the  increase 


in  latitude  and  that  on  the  south  western  wall  increases. 
It  would,  therefore,  be  advantageous  to  face  only 
smaller  surface  of  the  building  to  greater  solar  load  in 
the  summer  afternoons,  when  the  air  temperature  also 
is  higher. 

A-2.1.6  At  hill  stations,  winter  season  cause  more 
discomfort  and  so  sole  criterion  for  optimum  orientation 
should  be  based  on  receiving  maximum  solar  energy 
on  building  in  winter. 


48 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


ANNEX  B 

(' Clauses  4.2.5,  4. 2. 5.2,  4. 2. 5.4  and  4.2.6. 1) 

SKY  COMPONENT  TABLES 


B-l  DESCRIPTION  OF  TABLES 

B-l.l  The  three  sky  component  tables  are  as  given 
below: 


component  at  given  point  is  explained  with  help  of  the 
following  example. 

B-l. 6.2  Example 


a)  Table  15  —  Percentage  sky  components  on 

the  horizontal  plane  due  to  a 
vertical  rectangular  opening  for 
the  clear  design  sky. 

b)  Table  16  —  Percentage  sky  components  on 

the  vertical  plane  perpendicular 
to  a  vertical  rectangular  opening 
for  the  clear  design  sky. 

c)  Table  17  —  Percentage  sky  components  on 

the  vertical  plane  parallel  to  a 
vertical  rectangular  opening  for 
the  clear  design  sky. 

B-l. 2  All  the  tables  are  for  an  unglazed  opening 
illuminated  by  the  clear  design  sky. 

B-1.3  The  values  tabulated  are  the  components  at  a 
point  P  distant  from  the  opening  on  a  line  perpendicular 
to  the  plane  of  the  opening  through  one  of  its  lower 
corners,  and  /  and  h  are  the  width  and  height 
respectively  of  the  rectangular  opening  ( see  Fig.  13). 


Fig.  13 

B-1.4  Sky  component  for  different  hid  and  Hd  values 
are  tabulated,  that  is,  for  windows  of  different  size  and 
for  different  distances  of  the  point  P  from  the  window. 

B-l. 5  By  suitable  combination  of  the  values  obtained 
from  the  three  tables,  for  a  given  point  for  a  given 
window,  the  sky  component  in  any  plane  passing 
through  the  point  may  be  obtained. 

B-l. 6  Method  of  Using  the  Tables 

B-l. 6.1  Method  of  using  the  Tables  to  get  the  sky 


It  is  desired  to  calculate  the  sky  component  due  to  a 
vertical  window  ABCD  with  width  1.8  m  and  height 
1 .5  m  at  a  point  P  on  a  horizontal  plane  3.0  m  from  the 
window  wall  located  as  shown  in  the  Fig.  14.  Foot  of 
the  perpendicular  N  is  0.6  m  below  the  sill  and  0.9  m 
to  the  left  of  AD. 


0.9  m 


1.8  m 


Fig.  14 

Consider  ABCD  extended  to  NB'CD' 

1)  For  NB'CD' 

//4  =  (1.8  +  0.9)/3  =  0.9 
h/d=  (1.5  +  0.6)/3  =  0.7 
Fx  =  5.708  percent  (from  Table  15) 

2)  For  NA'DD' 
l/d  =  0.9/3  =  0.3 

Md=  (1.5  +  0.6)/3  =  0.7 

F2=  2.441  percent  (from  Table  15) 

3)  For  NB’BA' 

Hd  =  (1.8  +  0.9)/3  =  0.9 
h/d=  0.6/3  =  0.2 

F}  =  0.878  percent  (from  Table  15) 

4)  ForNA'AA’ 
lid  =  0.9/3  =  0.3 
h/d=  0.6/3  =  0.2 

F  =  0.403  percent  (from  Table  15) 


PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


49 


Since  ABCD  =  NB '  CD  '-NA'DD'-NB '  B  A '  +  NA '  AA ' 

Sky  Component,  F=  Fl-F2~F3  +  F4 

=  5.708  -  2.441  -  0.878  +  0.403 
=  2.792 

B-2  GENERAL  INSTRUCTIONS 

B-2.1  For  irregular  obstructions  like  row  of  trees 
parallel  to  the  plane  of  the  window,  equivalent  straight 
boundaries  horizontal  and  vertical,  may  be  drawn. 

B-2. 2  For  extremely  irregular  obstruction  or 
obstructions  not  in  a  plane  parallel  to  the  window, 
diagrammatic  methods,  such  as  Waldrams  diagrams 
may  have  to  be  employed. 

B-2.3  For  bay  windows,  dormer  windows  or  corner 
windows  the  effective  dimensions  of  window  opening 
computed  should  be  taken  when  using  the  tables  to  find 
the  sky  components. 

B-3  CALCULATION  OF  IRC 

B-3.1  The  internal  reflected  component  is  a  variable 
quantity  which  varies  from  point  to  point  in  a  room 
depending  upon  the  interior  finish.  IRC  value  is 
maximum  at  the  centre  of  the  room  and  decreases 
elsewhere  in  all  directions.  For  processing  calculations 
of  IRC  at  any  given  point  of  the  room,  special 
techniques  have  to  be  made  out.  The  internal  reflected 
component  may  be  calculated  by  using  the  formula: 

IRC  =  °'85H  (CR fw  + 1  OR  ) 
zl(l-R) 


Rjw  =  average  reflection  factor  of  the  floor  and 
those  parts  of  the  wall  below  the  plane  of 
the  mid-height  of  the  window  (excluding  the 
window  wall); 

Rc„  =  average  reflection  factor  of  the  ceiling  and 
those  parts  of  the  wall  above  the  plane  of 
the  mid-height  of  the  window  (excluding  the 
window  wall); 

A  =  area  of  all  the  surfaces  in  the  room  (ceiling 
walls,  floor  and  windows);  and 

R  =  average  reflection  factor  of  all  surfaces  in 
the  room  (ceiling,  walls,  floor  and  windows) 
expressed  as  a  decimal  part  of  unity. 

B-3.2  Example 

Consider  two  rooms  of  dimensions: 

Room  X  =  6  m  (/)  x  5  m  ( w )  x  3  m  ( ht ) 

Room  Y=  3.7  m  x  3  m  x  3  m 

Let  the  window  area  be  15  percent  of  the  floor  area 
and  be  glazed. 

Window  size  in  room  X  =  2.5  m  x  1.8  m 

Window  size  in  room  3.7  m  x  3  m 

The  window  are  on  the  Y=  6  m  x  3  m  side  in  room  X 
and  3.7  m  x  3  m  side  in  room  Y  and  the  sill  heights  are 
0.9  m  from  floor  level. 

Reflection  coefficients  of: 


where 

W  =  window  area; 

C  =  constant  of  value  7  8  when  there  is  no  external 
obstruction  but  it  has  different  values  as 
shown  in  the  following  table  when  there  are 
obstructions: 


Angle  of 
Obstruction 
Degree 
(1) 

Sky  +  External 
Obstruction,  C 

(2) 

5 

68.9 

15 

50.6 

25 

36.2 

35 

26.7 

45 

20.1 

55 

15.8 

65 

12.9 

75 

11.1 

85 

10.36 

walls  and  ceiling  =  70  percent 
floor  =  20  percent 

glazing  =15  percent 

Value  of  IRC  in  room  X: 

a)  Total  interior  area,  A=2  (3  0+18  +  15) 

=  126  m2 

b)  Average  reflection  factor  of  interior: 

n  61.5x0.7+30x0.7+30x0.2+4.5x0.15 

R  = - =  0.56 

61.5  +  30  +  30  +  4.5 

c)  l  -R  =  0.44 

d)  Mid-height  of  window  is  1.83  m  from  floor, 
average  reflection  factor  of  room  below 
1.83  m  level  excluding  the  wall  containing  the 
window: 


*fw  - 


29.28x0.7  +  30x0.2 
29.28  +  30 


0.45 


50 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


e)  Average  reflection  factor  of  room  above 
1.83m  level  excluding  the  wall  containing  the 
window: 


R 


CW 


18.72x0.7  +  30x0.7 
18.72  +  30 


f)  IRC  =  0  85  X  4’5  (78  x0.45  +  10  x0.7) 
126  x  0.44 v  ’ 

=  2.904 


Value  of  IRC  in  room  Y: 

a)  Total  interior  area: 

A  =  2(3.7 x3+ 3.7x3 +  3x3)  =  62.4  m2 

b)  Average  reflection  factor: 


38x55x0.7x3x0.7  +  3.7x3 
x0.2  +  1.5xl. 1x0.15 

38.55  +  11.1  +  11.1  +  1.65 


0.596 


c)  Mid-height  of  window  from  floor  =  1 .46  m 

d)  Average  reflection  factor  below  1 .46  m  level 

_  3.7x3x0.7  +  1.54x9.7x0.7 

Re.  —  —  U.  / 

11.1  +  14.94 


e) 


Average  reflection  factor  above  1 .46  m  level 
3.7x3x0.7  +  1.54x9.7x0.7 


R  „  = 


11.1  +  14.94 


=  0.7 


f) 


IRC  =  °'85xL65  (78  x  0.48  +  10  x  0.7) 
62.4  x  0.404 v  ’ 

=  2.472 


B-4  GENERAL  NOTE  ON  DAYLIGHTING  OF 
BUILDNG 

B-4.1  The  main  aim  of  day  lighting  design  is  how  to 
admit  enough  light  for  good  visibility  without  setting 
up  uncomfortable  glare.  No  simple  solution  may  be 


given  as  the  sky  varies  so  much  in  its  brightness  from 
hour  to  hour,  and  from  season  to  season. 

B-4.2  Different  visual  tasks  need  differing  amounts  of 
lights  for  the  same  visual  efficiency.  The  correct  amount 
of  light  for  any  task  is  determined  by  the  following: 

a)  Characteristics  of  the  tasks  —  Size  of 
significant  detail,  contrast  of  detail  with 
background  and  how  close  it  is  to  the  eyes; 

b)  Sight  of  the  worker  —  For  example,  old 
people  need  more  light; 

c)  Speed  and  accuracy  necessary  in  the 
performance  of  work.  If  no  errors  are 
permissible,  much  more  light  is  needed;  and 

d)  Ease  and  comfort  of  working  —  Long  and 
sustained  tasks  shall  be  done  easily  whereas 
workers  can  make  a  special  effort  for  tasks  of 
very  short  duration. 

These  factors  have  been  made  the  subject  of  careful 
analysis  as  a  result  of  which  tables  of  necessary  levels 
of  illumination  have  been  draw  up. 

B-4.3  Levels  of  lighting  determined  analytically  shall 
be  translated  into  levels  of  daylight  and  then  into  size 
of  window  opening  or  vice  versa  for  checking  the  size 
of  window  assumed  for  required  levels  of  daylight. 

B-4.4  One  of  the  many  important  factors  involved  in 
the  translation  is  the  lightness  of  the  room  surface.  The 
illumination  levels  in  a  given  room  with  a  finite  window 
will  be  higher  when  the  walls  are  light  coloured  than 
when  these  are  dark  coloured.  It  is  necessary,  therefore, 
at  an  early  stage  to  consider  the  colouring  of  the  rooms 
of  the  building  and  not  to  leave  this  until  later.  Lighting 
is  not  merely  a  matter  of  window  openings  and  quite 
half  the  eventual  level  of  lighting  may  be  dependent  on 
the  decoration  in  the  room.  Whatever  may  be  the  colour 
the  occupant  wants  to  use,  it  is  most  desirable  to 
maintain  proper  values  of  reflectance  factors  for  ceiling, 
wall  and  floors  so  that  the  level  of  daylight  illumination 
is  maintained. 


PART  8  BUILDING  SERVICES 


SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


51 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  15  Percentage  Sky  Components  on  the  Horizontal  Plane  Due  to  a  Vertical 
Rectangular  Opening  for  the  Clear  Design  Sky 

{Clauses  B-l.l  and  B-l.6.2) 


l/d 

h/d 

(1) 

0.1 

(2) 

0.2 

(3) 

0.3 

(4) 

0.4 

(5) 

0.5 

(6) 

0.6 

(7) 

0.7 

(8) 

0.8 

(9) 

0.9 

(10) 

1.0 

(ID 

1.1 

(12) 

1.2 

(13) 

1.3 

(14) 

1.4 

(15) 

1.5 

(16) 

1.6 

(17) 

1.7 

(18) 

1.8 

(19) 

1.9 

(20) 

2.0 

(21) 

3.0 

(22) 

4.0 

(23) 

5.0 

(24) 

10.0 

(25) 

INF 

(26) 

0.1 

0.036 

0.071 

0.104 

0.133 

0.158 

0.179 

0.198 

0.213 

0.225 

0.235 

0.243 

0.250 

0.256 

0.261 

0.264 

0.268 

0.270 

0.272 

0.274 

0.276 

0.284 

0.286 

0.287 

0.288 

0.288 

0.2 

0.141 

0.277 

0.403 

0.516 

0.614 

0.699 

0.770 

0.829 

0.878 

0.918 

0.950 

0.977 

0.999 

1.018 

1.033 

1.046 

1.056 

1.065 

1.072 

1.079 

1.110 

1.118 

1.122 

1.125 

1.125 

0.3 

0.300 

0.589 

0.859 

1.102 

1.315 

1.499 

1.653 

1.782 

1.888 

1.976 

2.048 

2.108 

2.157 

2.197 

2.231 

2.259 

2.282 

2.302 

2.318 

2.333 

2.401 

2.421 

2.429 

2.436 

2.437 

0.4 

0.460 

0.905 

1.322 

1.702 

2.041 

2.337 

2.590 

2.804 

2.984 

3.134 

3.258 

3.361 

3.446 

3.516 

3.574 

3.623 

3.664 

3.699 

3.728 

3.753 

3.873 

3.909 

3.922 

3.935 

3.937 

0.5 

0.604 

1.189 

1.741 

2.247 

2.700 

3.099 

3.444 

3.740 

3.992 

4.204 

3.383 

4.553 

4.659 

4.765 

4.853 

4.928 

4.990 

5.043 

5.088 

5.126 

5.312 

5.366 

5.387 

5.408 

5.410 

0.6 

0.732 

1.443 

2.114 

2.732 

3.289 

3.781 

4.211 

4.582 

4.900 

5.171 

5.401 

5.596 

5.761 

5.901 

6.020 

6.121 

6.208 

6.281 

6.344 

6.397 

6.661 

6.739 

6.769 

6.798 

6.802 

0.7 

0.844 

1.665 

2.441 

3.159 

3.808 

4.385 

4.891 

5.330 

5.708 

6.034 

6.311 

6.548 

6.751 

6.924 

7.071 

7.198 

7.307 

7.400 

7.481 

7.551 

7.902 

8.006 

8.047 

8.087 

8.092 

0.8 

0.942 

1.858 

2.727 

3.532 

4.262 

4.914 

5.488 

5.989 

6.423 

6.798 

7.119 

7.395 

7.632 

7.836 

8.011 

8.162 

8.292 

8.405 

8.502 

8.587 

9.029 

9.164 

9.217 

9.268 

9.276 

0.9 

1.026 

2.025 

2.974 

3.855 

4.657 

5.375 

6.011 

6.567 

7.051 

7.470 

7.832 

8.144 

8.413 

8.645 

8.846 

9.019 

9.170 

9.301 

9.415 

9.515 

10.045 

10.214 

10.280 

10.345 

10.355 

1.0 

1.099 

2.169 

3.188 

4.135 

5.000 

5.776 

6.465 

7.071 

7.600 

8.060 

8.458 

8.803 

9.102 

9.361 

9.585 

9.780 

9.950 

10.098 

10.228 

10.343 

10.957 

11.162 

11.243 

11.323 

11.335 

1.1 

1.161 

2.294 

3.372 

4.377 

5.296 

6.124 

6.861 

7.510 

8.079 

8.576 

9.008 

9.383 

9.709 

9.992 

10.239 

10.454 

10.642 

10.806 

10.951 

11.078 

11.776 

12.017 

12.114 

12.209 

12.224 

1.2 

1.215 

2.401 

3.531 

4.586 

5.553 

6.425 

7.204 

7.893 

8.498 

9.027 

9.489 

9.892 

10.243 

10.549 

10.816 

11.050 

11.254 

11.434 

11.593 

11.732 

12.509 

12.786 

12.900 

13.013 

13.030 

1.3 

1.262 

2.493 

3.668 

4.767 

5.775 

6.687 

7.503 

8.226 

8.863 

9.422 

9.912 

10.339 

10.713 

11.040 

11.326 

11.577 

11.797 

11.992 

12.163 

12.314 

13.167 

13.478 

13.609 

13.742 

13.762 

1.4 

1.302 

2.573 

3.787 

4.924 

5.968 

6.915 

7.764 

8.517 

9.183 

9.769 

10.283 

10.733 

11.127 

11.473 

11.777 

12.044 

12.279 

12.487 

12.670 

12.833 

13.758 

14.102 

14.251 

14.404 

14.427 

1.5 

1.337 

2.643 

3.891 

5.060 

6.136 

7.114 

7.991 

8.772 

9.664 

10.073 

10.609 

11.080 

11.493 

11.857 

12.176 

12.458 

12.707 

12.927 

13.122 

13.295 

14.289 

14.666 

14.832 

15.006 

15.033 

1.6 

1.367 

2.703 

3.981 

5.179 

6.283 

7.287 

8.190 

8.996 

9.710 

10.341 

10.897 

11.386 

11.817 

12.196 

12.531 

12.826 

13.088 

13.319 

13.525 

13.708 

14.768 

15.176 

15.359 

15.555 

15.585 

1.7 

1.394 

2.756 

4.060 

5.283 

6.412 

7.440 

8.366 

9.192 

9.927 

10.577 

11.151 

11.657 

12.104 

12.498 

12.846 

13.154 

13.427 

13.669 

13.885 

14.078 

15.199 

15.638 

15.838 

16.056 

16.091 

1.8 

1.417 

2.803 

4.129 

5.375 

6.526 

7.574 

8.520 

9.366 

10.119 

10.786 

11.376 

11.898 

12.359 

12.766 

13.127 

13.446 

13.730 

13.983 

14.208 

14.409 

15.590 

16.058 

16.274 

16.516 

16.554 

1.9 

1.438 

2.844 

4.190 

5.456 

6.626 

7.693 

8.656 

9.520 

10.289 

10.972 

11.577 

12.112 

12.587 

13.006 

13.378 

13.708 

14.002 

14.264 

14.498 

14.707 

15.944 

16.441 

16.673 

16.937 

16.980 

2.0 

1.456 

2.880 

4.244 

5.527 

6.714 

7.798 

8.778 

9.656 

10.440 

11.137 

11.755 

12.303 

12.789 

13.220 

13.603 

13.943 

14.246 

14.516 

14.758 

14.975 

16.265 

16.790 

17.037 

17.325 

17.372 

3.0 

1.559 

3.087 

4.553 

5.937 

7.223 

8.403 

9.478 

10.448 

11.321 

12.103 

12.804 

13.431 

13.993 

14.496 

14.947 

15.353 

15.718 

16.048 

16.346 

16.676 

18.301 

19.051 

19.432 

19.943 

20.046 

4.0 

1.600 

3.168 

4.676 

6.100 

7.426 

8.646 

9.759 

10.768 

11.678 

12.498 

13.235 

13.897 

14.493 

15.030 

15.514 

15.951 

16.347 

16.706 

17.033 

17.330 

19.241 

20.142 

20.623 

21.322 

21.495 

5.0 

1.620 

3.208 

4.735 

6.179 

7.525 

8.765 

9.897 

10.925 

11.854 

12.693 

13.448 

14.128 

14.742 

15.296 

15.798 

16.252 

16.664 

17.040 

17.382 

17.695 

19.740 

20.740 

21.293 

22.148 

22.393 

10.0 

1.648 

3.263 

4.818 

6.289 

7.662 

8.930 

10.089 

11.144 

12.100 

12.965 

13.747 

14.454 

15.094 

15.674 

16.201 

16.681 

17.118 

17.518 

17.885 

18.222 

20.491 

21.681 

22.390 

23.676 

24.238 

INF 

1.657 

3.282 

4.846 

6.327 

7.710 

8.986 

10.155 

11.220 

12.186 

13.060 

13.851 

14.567 

15.217 

15.806 

16.342 

16.831 

17.278 

17.688 

18.064 

18.410 

20.770 

22.046 

22.838 

24.463 

26.111 

PART  8  BUILDING  SERVICES  —  SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


Table  16  Percentage  Sky  Components  on  the  Vertical  Plane  Perpendicular 
to  a  Vertical  Rectangular  Opening  for  the  Clear  Design  Sky 

( Clause  B-l.l) 


l/d 

h/rf 

0.1 

0.2 

0.3 

0.4 

0.5 

0.6 

0.7 

0.8 

0.9 

1.0 

1.1 

1.2 

1.3 

1.4 

1.5 

1.6 

1.7 

1.8 

1.9 

2.0 

3.0 

4.0 

5.0 

10.0 

INF 

(i) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

(9) 

(10) 

(11) 

(12) 

(13) 

(14) 

(15) 

(16) 

(17) 

(18) 

(19) 

(20) 

(21) 

(22) 

(23) 

(24) 

(25) 

(26) 

0.1 

0.036 

0.141 

0.303 

0.506 

0.734 

0.971 

1.207 

1.432 

1.643 

2.836 

1.011 

2.168 

2.308 

2.433 

2.544 

2.642 

2.730 

2.808 

2.878 

2.940 

3.309 

3.461 

3.536 

3.641 

3.678 

0.2 

0.071 

0.277 

0.594 

0.993 

1.442 

1.910 

2.374 

2.820 

3.236 

3.618 

3.964 

4.276 

4.554 

4.802 

5.022 

5.219 

5.393 

5.549 

5.688 

5.812 

6.547 

6.850 

7.000 

7.211 

7.284 

0.3 

0.103 

0.401 

0.863 

1.445 

2.100 

2.793 

3.475 

4.180 

4.743 

5.306 

5.818 

6.278 

6.690 

7.058 

7.385 

7.677 

7.936 

8.168 

8.375 

8.560 

9.657 

10.110 

10.335 

10.651 

10.760 

0.4 

0.126 

0.491 

1.059 

1.779 

2.597 

3.460 

4.326 

5.166 

5.958 

6.691 

7.359 

7.967 

8.507 

8.900 

9.420 

9.804 

10.146 

10.451 

10.724 

10.968 

12.421 

13.024 

13.323 

13.743 

13.889 

0.5 

0.142 

0.554 

1.197 

2.015 

2.947 

3.937 

4.938 

5.914 

6.842 

7.707 

8.503 

9.228 

9.883 

10.472 

10.999 

11.476 

11.897 

12.273 

12.610 

12.912 

14.712 

15.462 

15.835 

16.360 

16.542 

0.6 

0.154 

0.600 

1.298 

2.187 

3.204 

4.288 

5.389 

6.468 

7.498 

8.464 

9.358 

10.177 

10.922 

11.596 

12.204 

12.752 

13.244 

13.686 

14.084 

14.441 

16.583 

17.478 

17.924 

18.552 

18.771 

0.7 

0.162 

0.634 

1.372 

2.316 

3.397 

4.552 

5.729 

6.887 

7.997 

9.042 

10.013 

10.907 

11.723 

12.465 

13.138 

13.746 

14.296 

14.793 

15.241 

15.646 

18.111 

19.148 

19.665 

20.397 

20.653 

0.8 

0.169 

0.660 

1.429 

2.413 

3.543 

4.754 

5.990 

7.209 

8.382 

9.490 

10.523 

11.476 

12.350 

13.147 

13.873 

14.531 

15.129 

15.670 

16.161 

16.606 

19.361 

20.538 

21.127 

21.961 

22.253 

0.9 

0.174 

0.680 

1.472 

2.487 

3.655 

4.909 

6.192 

7.460 

8.683 

9.841 

10.924 

11.926 

12.847 

13.690 

14.459 

15.159 

15.796 

16.375 

16.902 

17.381 

20.387 

21.701 

22.360 

23.397 

23.625 

1.0 

0.178 

0.695 

1.505 

2.545 

3.743 

5.030 

6.350 

7.657 

8.921 

10.120 

11.243 

12.284 

13.245 

14.126 

14.931 

15.666 

16.337 

16.948 

17.504 

18.012 

21.237 

22.680 

23.408 

24.446 

24.810 

1.1 

0.181 

0.707 

1.532 

2.591 

3.812 

5.126 

6.475 

7.814 

9.110 

10.342 

11.498 

12.573 

13.356 

14.478 

15.314 

16.079 

16.778 

17.416 

17.999 

18.531 

21.946 

23.508 

24.303 

25.441 

25.841 

1.2 

0.183 

0.716 

1.552 

2.626 

3.866 

5.202 

6.575 

7.939 

9.261 

10.521 

11.705 

12.807 

13.827 

14.766 

15.628 

16.418 

17.141 

17.802 

18.407 

18.961 

22.543 

24.208 

25.072 

26.309 

26.745 

1.3 

0.185 

0.723 

1.568 

2.655 

3.910 

5.263 

6.655 

8.040 

9.384 

10.666 

11.873 

12.998 

14.041 

15.003 

15.887 

16.698 

17.442 

18.123 

18.747 

19.320 

23.049 

24.809 

25.735 

27.070 

27.542 

1.4 

0.186 

0.729 

1.582 

2.678 

3.945 

5.312 

6.720 

8.122 

9.484 

10.785 

12.011 

13.155 

14.217 

15.198 

16.101 

16.931 

17.692 

18.391 

19.032 

19.621 

23.480 

25.326 

26.308 

27.441 

28.249 

1.5 

0.188 

0.734 

1.592 

2.697 

3.973 

5.352 

6.773 

8.189 

9.566 

10.883 

12.124 

13.285 

14.364 

15.361 

16.280 

17.125 

17.902 

18.616 

19.272 

19.875 

23.850 

25.772 

26.808 

28.336 

28.880 

1.6 

0.189 

0.738 

1.601 

2.712 

3.996 

5.385 

6.816 

8.244 

9.634 

10.963 

12.219 

13.394 

14.486 

15.497 

16.430 

17.289 

18.079 

18.806 

19.475 

20.090 

24.169 

26.161 

27.245 

28.866 

29.445 

1.7 

0.189 

0.741 

1.608 

2.724 

4.016 

5.412 

6.852 

8.290 

9.690 

11.031 

12.298 

13.484 

14.589 

15.511 

16.556 

17.427 

18.229 

18.968 

19.648 

20.274 

24.444 

26.501 

27.629 

29.340 

29.955 

1.8 

0.190 

0.744 

1.614 

2.735 

4.032 

5.434 

6.882 

8.328 

9.737 

11.087 

12.364 

13.561 

14.675 

15.708 

16.663 

17.545 

18.357 

19.105 

19.795 

20.431 

24.684 

26.799 

27.969 

29.765 

30.416 

1.9 

0.191 

0.746 

1.619 

2.743 

4.045 

5.453 

6.908 

8.360 

9.777 

11.135 

12.420 

13.625 

14.749 

15.791 

16.755 

17.645 

18.466 

19.224 

19.922 

20.567 

24.893 

27.062 

28.270 

30.149 

30.835 

2.0 

0.191 

0.748 

1.623 

2.751 

4.056 

5.469 

6.929 

8.387 

9.811 

11.175 

12.468 

13.680 

14.811 

15.861 

16.833 

17.731 

18.560 

19.325 

20.031 

20.684 

25.077 

27.294 

28.537 

30.496 

31.217 

3.0 

0.193 

0.756 

1.642 

2.785 

4.109 

5.544 

7.030 

8.517 

9.972 

11.371 

12.699 

13.950 

15.120 

16.211 

17.224 

18.164 

19.036 

19.844 

20.594 

21.289 

26.082 

28.619 

30.108 

32.676 

32.742 

4.0 

0.194 

0.759 

1.648 

2.794 

4.124 

5.566 

7.058 

8.540 

10.018 

11.427 

12.767 

14.029 

15.212 

16.316 

17.343 

18.298 

19.185 

20.008 

20.772 

21.483 

26.439 

29.128 

30.745 

33.687 

35.064 

5.0 

0.194 

0.760 

1.650 

2.798 

4.129 

5.574 

7.069 

8.568 

10.036 

11.449 

12.793 

14.060 

15.248 

16.357 

17.390 

18.351 

19.243 

20.073 

20.844 

21.562 

26.592 

29.359 

31.049 

34.232 

35.872 

10.0 

0.194 

0.761 

1.652 

2.801 

4.135 

5.581 

7.080 

8.582 

10.053 

11.470 

12.818 

14.095 

15.283 

16.398 

17.436 

18.403 

19.302 

20.138 

20.917 

21.641 

26.758 

29.624 

31.419 

35.049 

37.513 

INF 

0.194 

0.761 

1.652 

2.802 

4.136 

5.582 

7.081 

8.584 

10.056 

11.473 

12.822 

14.095 

15.288 

16.404 

17.443 

18.411 

19.311 

20.148 

20.928 

21.654 

26.785 

29.672 

31.490 

35.274 

39.172 

'ji 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  17  Percentage  Sky  Components  on  the  Vertical  Plane  Parallel 
to  a  Vertical  Rectangular  Opening  for  the  Clear  Design  Sky 

( Clause  B-l.l) 


l/d 

h/H 

0.1 

0.2 

0.3 

0.4 

0.5 

0.6 

0.7 

0.8 

0.9 

1.0 

1.1 

1.2 

1.3 

1.4 

1.5 

1.6 

1.7 

1.8 

1.9 

2.0 

3.0 

4.0 

5.0 

10.0 

INF 

(i) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

(9) 

(10) 

(11) 

(12) 

(13) 

(14) 

(15) 

(16) 

(17) 

(18) 

(19) 

(20) 

(21) 

(22) 

(23) 

(24) 

(25) 

(26) 

0.1 

0.728 

1.429 

2.078 

2.600 

3.167 

3.660 

3.964 

4.265 

4.513 

4.717 

4.883 

5.020 

5.132 

5.225 

5.301 

5.365 

5.418 

5.463 

5.501 

5.533 

5.687 

5.733 

5.749 

5.765 

5.766 

0.2 

1.429 

2.803 

4.007 

5.221 

6.220 

7.073 

7.790 

8.385 

8.876 

9.278 

9.609 

9.880 

10.103 

10.286 

10.439 

10.565 

10.671 

10.760 

10.835 

10.899 

11.207 

11.296 

11.330 

11.362 

11.365 

0.3 

2.068 

4.061 

5.913 

7.580 

9.040 

10.285 

11.337 

12.212 

12.934 

13.528 

14.016 

14.417 

14.747 

15.020 

15.246 

15.434 

15.591 

15.724 

15.836 

15.931 

16.390 

16.523 

16.574 

16.623 

16.627 

0.4 

2.529 

4.970 

7.249 

9.312 

11.133 

12.707 

14.042 

15.164 

16.097 

16.870 

17.507 

18.025 

18.458 

18.816 

19.113 

19.360 

19.568 

19.742 

19.890 

20.015 

20.624 

20.801 

20.868 

20.933 

20.939 

0.5 

2.852 

5.608 

8.186 

10.529 

12.606 

14.401 

15.952 

17.256 

18.350 

19.262 

20.021 

20.652 

21.177 

21.613 

21.978 

22.275 

22.530 

22.746 

22.923 

23.082 

23.836 

24.056 

24.140 

24.222 

24.229 

0.6 

3.086 

6.070 

8.867 

11.415 

13.681 

15.656 

17.353 

18.793 

20.008 

21.027 

21.879 

22.592 

23.189 

23.689 

24.109 

24.462 

24.761 

25.014 

25.229 

25.412 

26.229 

26.561 

26.662 

26.759 

26.768 

0.7 

3.259 

6.413 

9.373 

12.074 

14.482 

16.588 

18.402 

19.949 

21.257 

22.359 

23.285 

24.063 

24.716 

25.267 

25.731 

26.124 

26.458 

26.742 

26.984 

27.192 

28.214 

28.517 

28.634 

28.748 

28.758 

0.8 

3.389 

6.672 

9.755 

12.573 

15.090 

17.296 

19.201 

20.830 

22.212 

23.380 

24.365 

25.195 

25.895 

26.486 

26.987 

27.412 

27.775 

28.084 

28.350 

28.578 

29.720 

30.065 

30.198 

30.327 

30.339 

0.9 

3.489 

6.869 

10.046 

12.955 

15.556 

17.840 

19.817 

21.511 

22.952 

24.173 

25.206 

26.078 

26.816 

27.441 

27.972 

28.424 

28.810 

29.141 

29.426 

29.672 

30.927 

31.303 

31.451 

31.596 

31.610 

1.0 

3.565 

7.024 

10.272 

13.250 

15.917 

18.263 

20.297 

22.043 

23.531 

24.795 

25.866 

26.773 

27.542 

28.196 

28.572 

29.226 

29.633 

29.982 

30.283 

30.544 

31.889 

32.302 

32.467 

32.627 

32.643 

1.1 

3.625 

7.139 

10.447 

13.481 

16.200 

18.594 

20.674 

22.462 

23.989 

25.288 

26.391 

27.326 

28.121 

28.798 

29.375 

29.869 

30.293 

30.658 

30.973 

31.246 

32.670 

33.117 

33.297 

33.473 

33.491 

1.2 

3.672 

7.233 

10.586 

13.663 

16.423 

18.857 

20.973 

22.795 

24.353 

25.681 

26.810 

27.770 

28.587 

29.283 

29.878 

30.388 

30.826 

31.204 

31.532 

31.816 

33.309 

33.796 

33.981 

34.173 

34.193 

1.3 

3.709 

7.307 

10.696 

13.807 

16.602 

19.067 

21.213 

23.062 

24.646 

25.998 

27.148 

28.128 

28.963 

29.676 

30.286 

30.810 

31.261 

31.651 

31.989 

32.283 

33.836 

34.350 

34.550 

34.756 

34.779 

1.4 

3.739 

7.366 

10.784 

13.924 

16.745 

19.236 

21.406 

23.278 

24.884 

26.255 

27.424 

28.420 

29.271 

29.998 

30.621 

31.157 

31.618 

32.018 

32.365 

32.667 

34.374 

34.813 

35.035 

35.247 

35.271 

1.5 

3.763 

7.414 

10.856 

14.018 

16.861 

19.373 

21.563 

23.454 

25.077 

26.465 

27.649 

28.660 

29.523 

30.262 

30.897 

31.443 

31.914 

32.322 

32.677 

32.986 

34.641 

35.202 

35.436 

35.663 

35.689 

1.6 

3.783 

7.453 

10.914 

14.095 

16.956 

19.485 

21.692 

23.599 

25.236 

26.638 

27.835 

28.857 

29.732 

30.482 

31.226 

31.680 

32.160 

32.575 

32.937 

33.253 

34.950 

35.532 

35.776 

36.017 

36.046 

1.7 

3.799 

7.485 

10.962 

14.158 

17.034 

19.578 

21.798 

23.718 

25.368 

26.781 

27.989 

29.022 

29.906 

30.665 

31.317 

31.879 

32.366 

32.888 

33.156 

33.477 

35.211 

35.812 

36.067 

36.321 

36.352 

1.8 

3.812 

7.512 

11.002 

14.211 

17.099 

19.655 

21.886 

23.817 

25.478 

26.900 

28.118 

29.160 

30.052 

30.818 

31.477 

32.046 

32.539 

32.967 

33.340 

33.666 

35.435 

36.052 

36.316 

36.584 

36.617 

1.9 

3.824 

7.534 

11.035 

14.254 

17.153 

19.719 

21.960 

23.900 

25.570 

27.001 

28.226 

26.276 

30.175 

30.948 

31.613 

32.188 

32.686 

33.119 

33.497 

33.828 

35.626 

35.259 

36.532 

36.812 

36.847 

2.0 

3.833 

7.553 

11.062 

14.291 

17.199 

19.773 

22.022 

23.970 

25.647 

27.086 

28.318 

29.374 

31.279 

31.058 

31.728 

32.308 

32.811 

33.249 

33.631 

33.965 

35.791 

36.438 

36.719 

37.011 

37.048 

3.0 

3.876 

7.639 

11.192 

14.463 

17.412 

20.027 

22.316 

24.302 

26.016 

27.491 

28.757 

29.846 

30.783 

31.592 

32.291 

32.898 

33.427 

33.889 

34.294 

34.551 

36.640 

37.380 

37.715 

38.107 

38.157 

4.0 

3.888 

7.663 

11.228 

14.511 

17.471 

20.098 

22.398 

24.398 

26.121 

27.606 

28.884 

29.983 

30.930 

31.748 

32.457 

33.074 

33.611 

34.082 

34.496 

34.860 

36.915 

37.699 

38.063 

38.510 

38.579 

5.0 

3.893 

7.672 

11.241 

14.529 

17.494 

20.125 

22.430 

24.432 

26.161 

27.650 

28.932 

30.035 

30.986 

31.808 

32.521 

33.142 

33.683 

34.157 

34.574 

34.943 

37.028 

37.834 

38.214 

38.696 

38.781 

10.0 

3.897 

7681 

11.254 

14.546 

17.515 

20.150 

22.459 

24.466 

26.199 

27.693 

28.978 

30.085 

31.041 

31.867 

32.584 

33.208 

33.753 

34.231 

34.652 

35.024 

37.144 

37.978. 

38.382 

38.927 

39.057 

INF 

3.898 

7.682 

11.256 

44.548 

17.518 

20.154 

22.464 

24.471 

26.205 

27.699 

28.985 

30.093 

31.049 

31.876 

32.593 

33.218 

33.764 

34.243 

34.664 

35.037 

37.162 

38.003 

38.411 

38.978 

39.172 

LIST  OF  STANDARDS 


The  following  list  records  those  standards  which  are  IS  No. 


acceptable  as  ‘good  practice’  and  ‘accepted  standards’ 
in  the  fulfillment  of  the  requirements  of  the  Code.  The 

7942  :  1976 

latest  version  of  a  standard  shall  be  adopted  at  the  time 
of  enforcement  of  the  Code.  The  standards  listed  may 

(5) 

1944 

be  used  by  the  Authority  for  conformance  with  the 

(Parts  1  and  2) 

requirements  of  the  referred  clauses  in  the  Code. 

1970 

In  the  following  list,  the  number  appearing  in  first 
column  within  parentheses  indicates  the  number  of  the 
reference  in  this  Section. 

Part  6  :  1981 

IS  No. 

Title 

2672  :  1966 

(1)  7662 

Recommendations  for  orientation 

4347  :  1967 

(Part  1)  :  1974 

ofbuildings:  Part  1  Non-industrial 
buildings 

6074  :  1971 

(2)  3646 

Code  of  practice  for  interior 

(Part  1) :  1992 

illumination:  Part  1  General 
requirements  and  recommen¬ 

6665  :  1972 

dations  for  building  interiors  (first 
revision) 

10894  :  1984 

(3)  2440  :  1975 

Guide  for  daylighting  ofbuildings 
(second  revision) 

10947  :  1984 

(4)  6060  :  1971 

Code  of  practice  for  day  lighting 
of  factory  buildings 

(6) 

3362  :  1977 

Title 

Code  of  practice  for  day  lighting 
of  educational  buildings 
Code  of  practice  for  lighting  of 
public  thoroughfares: 

:  Parts  1  and  2  For  main  and 
secondary  roads  (Group  A  and  B) 
(first  revision) 

Lighting  for  town  and  city  centres 
and  areas  of  civic  importance 
(Group  E) 

Code  of  practice  for  library  lighting 
Code  of  practice  for  hospital 
lighting 

Functional  requirements  of  hotels, 
restaurants  and  other  food  service 
establishments 

Code  of  practice  for  industrial 
lighting 

Code  of  practice  for  lighting  of 

educational  institutions 

Code  of  practice  for  lighting  for 

ports  and  harbours 

Code  of  practice  for  natural 

ventilation  of  residential  buildings 

(first  revision) 


PART  8  BUILDING  SERVICES 


SECTION  1  LIGHTING  AND  NATURAL  VENTILATION 


55 


NATIONAL  BUILDING  CODE  OF  INDIA 

PART  8  BUILDING  SERVICES 

Section  2  Electrical  and  Allied  Installations 


BUREAU  OF  INDIAN  STANDARDS 


CONTENTS 


FOREWORD  ...  3 

1  SCOPE  ...  7 

2  TERMINOLOGY  AND  CONVENTIONAL  SYMBOLS  ...  7 

3  GENERAL  REQUIREMENTS  ...  17 

4  PLANNING  OF  ELECTRICAL  INSTALLATIONS  ...  18 

5  DISTRIBUTION  OF  SUPPLY  AND  CABLING  ...30 

6  WIRING  ...  47 

7  FITTINGS  AND  ACCESSORIES  ...  56 

8  EARTHING  ...  61 

9  INSPECTION,  TESTING  AND  VERIFICATION  OF  INSTALLATION  ...  72 

10  ALLIED/MISCELLANEOUS  SERVICES  ...  77 

11  LIGHTNING  PROTECTION  OF  BUILDINGS  ...  81 

1 2  ELECTRICAL  INSTALLATIONS  FOR  CONSTRUCTION  AND  DEMOLITION  ...  1 1 1 
SITES 

13  PROTECTION  OF  HUMAN  BEINGS  FROM  ELECTRICAL  HAZARDS  ...118 

ANNEX  A  DRAWING  SYMBOLS  FOR  ELECTRICAL  INSTALLATIONS  ...  124 

IN  BUILDINGS 

ANNEX  B  EXTRACTS  FROM  CENTRAL  ELECTRICITY  AUTHORITY  ...  1 29 

(MEASURES  RELATING  TO  SAFETY  AND  ELECTRIC  SUPPLY) 
REGULATION,  2010  FURTHER  AMENDED  IN  2015 

ANNEX  C  AREA  REQUIRED  FOR  TRANSFORMER  ROOM  AND  ...  1 50 

SUBSTATION  FOR  DIFFERENT  CAPACITIES 

ANNEX  D  ADDITIONAL  AREA  REQUIRED  FOR  GENERATOR  IN  ELECTRIC  ...150 
SUBSTATION 

ANNEXE  CHECKLIST  FOR  INSPECTION,  HANDING  OVER  AND  ...151 

COMMISSIONING  OF  VARIOUS  EQUIPMENT  OF  SUBSTATION 

ANNEX  F  CHECKLIST  FOR  INSPECTION,  HANDING  OVER  AND  ...  1 6 1 

COMMISSIONING  OF  EARTHING  PITS 

ANNEX  G  FORM  OF  COMPLETION  CERTIFICATE  ...  1 63 

LIST  OF  STANDARDS  ...  166 


2 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


National  Building  Code  Sectional  Committee,  CED  46 


FOREWORD 

This  Code  (Part  8/Section  2)  covers  essential  requirements  for  electrical  and  allied  installations  in  buildings. 

This  Section  was  first  published  in  1970  and  was  subsequently  revised  in  1983  and  2005.  In  the  first  revision, 
general  guidance  for  electrical  wiring  installation  in  industrial  location  where  voltage  supply  normally  exceeds 
650  V  was  included.  This  Section  was  also  updated  based  on  the  existing  version  of  the  Indian  Standards.  The 
importance  of  pre-planning  and  exchange  of  information  among  all  concerned  agencies  from  the  earlier  stages  of 
building  work  was  emphasized. 

In  the  second  revision  of  2005,  the  title  of  this  Section  was  modified  from  the  erstwhile  ‘Electrical  Installations’ 
to  ‘Electrical  and  Allied  Installations’  to  reflect  the  provisions  included  on  certain  allied  installations.  The  significant 
changes  incorporated  in  the  last  revision  included,  thorough  change  in  the  risk  assessment  procedure  for  lightning 
including  some  other  changes  in  the  provision  of  lightning  protection  of  building;  alignment  of  some  of  the 
provisions  of  wiring  with  the  practices  prevalent  at  that  time;  modification  of  definitions  in  line  with  terminologies 
used  at  national  and  international  level  and  addition  of  some  new  definitions;  incorporation  of  provisions  on 
installation  of  distribution  transformer  inside  the  multi-storeyed  building;  introduction  of  concept  of  energy 
conservation  in  lighting  and  introduction  of  concept  of  various  types  of  earthing  in  building  installation. 

All  electrical  installations  in  India  come  under  the  purview  of  The  Indian  Electricity  Act,  2003  and  the  rules  and 
regulations  framed  thereunder.  In  the  context  of  the  buildings,  both  buildings  (the  structure  itself)  and  the  building 
services  (not  just  the  electrical  services,  but  all  other  services  that  use  electricity  or  have  an  interface  with  the 
electrical  system)  are  required  to  follow  these.  The  erstwhile  Indian  Electricity  Rules,  1956  were  superseded  by 
various  Central  Electricity  Authority  Regulations.  While  revising  the  provisions  of  this  Section  of  the  Code,  care 
has  been  taken  to  align  the  same  with  the  provisions  of  the  relevant  regulations,  particularly,  Central  Electricity 
Authority  (Measures  Relating  to  Safety  and  Electric  Supply)  Regulations,  2010,  amended  in  20 15.  In  this  revision, 
in  addition  to  above,  the  following  major  modifications  have  been  incorporated: 

a)  Various  new  terms  and  their  definitions  have  been  added  and  existing  terms  and  definitions  have  also 
been  updated  based  on  current  developments  at  national  and  international  level. 

b)  Provisions  relating  to  location  and  other  requirements  relating  to  layout,  environmental  and  safety  aspects 
for  different  substation  apparatus/equipment  and  generating  sets  have  been  reviewed  and  updated. 

c)  Provisions  relating  to  location  of  compact  substations  have  been  added. 

d)  Requirements  for  electrical  supply  system  for  life  and  safety  services  have  been  included. 

e)  Provisions  relating  to  reception  and  distribution  of  supply  and  wiring  installations  have  been  updated 
with  due  cognizance  to  Indian  Standards  formulated  for  various  wiring  systems. 

f)  Provisions  relating  to  installation  of  energy  meters  have  been  updated. 

g)  Discrimination,  cascading  and  limitation  concepts  for  the  coordination  of  protective  devices  in  electrical 
circuits  have  been  introduced. 

h)  Socket  outlets  with  suitable  circuit  breakers,  conforming  to  following  Indian  Standards  have  been 
recommended  for  industrial  and  commercial  applications,  either  indoors  or  outdoors: 

1)  1S/1EC  60309-1:2002  ‘Plugs,  socket-outlets  and  couplers  for  industrial  purposes  —  Part  1: 
General  requirements’;  and 

2)  1S/1EC  60309-2:2002  ‘Plugs,  socket-outlets  and  couplers  for  industrial  purposes  —  Part  2: 
Dimensional  Interchangeability  Requirements  for  Pin  and  Contact-Tube  Accessories’. 

j)  Provisions  relating  to  earthing/grounding  have  been  substantially  revised  and  updated. 

k)  Provisions  relating  to  lightning  protection  of  buildings  have  been  revamped  based  on  the  current  national 
and  international  developments. 

m)  Provisions  relating  to  renewable  energy  sources  for  building,  such  as  solar  PV  system;  aviation  obstacle 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


3 


lights;  electrical  supply  for  electric  vehicle  charging  and  car  park  management;  etc,  have  been  included. 

n)  New  provisions  relating  to  electrical  installations  for  construction  sites  and  demolition  sites  have  been 
included. 

p)  New  provisions  relating  to  protection  of  human  beings  from  electrical  hazards  and  protection  against 
fire  in  the  building  due  to  leakage  current  have  been  included. 

q)  Typical  formats  for  checklists  for  handing  over  and  commissioning  of  substation  equipment  and  earthing 
pit  have  been  included. 

This  Section  has  to  be  read  together  with  Part  8  ‘Building  Services,  Section  1  Lighting  and  Natural  Ventilation’  of 
the  Code  for  making  provision  for  the  desired  levels  of  illumination  as  well  as  ventilation  for  different  locations 
in  different  occupancies;  and  also  with  Part  4  ‘Fire  and  Life  Safety’  of  the  Code  for  list  of  emergency  fire  and  life 
safety  services  and  other  sections  of  Part  8  ‘Building  Services’  and  Part  9  ‘Plumbing  Services’  for  electricity 
related  requirements  and  integration  thereof.  Utmost  importance  should  be  given  in  the  installation  of  electrical 
wiring  to  prevent  short  circuiting  and  the  hazards  associated  therewith. 

Notwithstanding  the  provisions  given  in  this  Section  and  the  National  Electrical  Code,  2011  the  provisions  of  the 
Indian  Electricity  Act,  2003  and  the  rules  and  regulations  framed  thereunder  have  to  be  necessarily  complied 
with. 


The  information  contained  in  this  Section  is  largely  based  on  the  following  Indian  Standards/Special  Publication: 


IS  732  :  1989 
IS  3043  :  1987 
IS  4648:  1968 
IS  12032  (Part  11)  :  1987 

IS/IEC  62305-1  :  2010 
IS/IEC  62305-2  :  2010 
IS/IEC  62305-3  :  2010 
IS/IEC  62305-4  :  2010 
SP  30  :  2011 


Code  of  practice  for  electrical  wiring  installations  ( third  revision)  ( under  revision ) 
Code  of  practice  for  earthing  (first  revision)  {under  revision) 

Guide  for  electrical  layout  in  residential  buildings 

Specification  for  graphical  symbols  for  diagrams  in  the  field  of  electro  technology: 
Part  1 1  Architectural  and  topographical  installation  plan  and  diagrams 
Protection  against  lightning:  Part  1  General  principles 
Protection  against  lightning:  Part  2  Risk  management 

Protection  against  lightning:  Part  3  Physical  damage  to  structures  and  life  hazard 
Protection  against  lightning:  Part  4  Electrical  and  electronic  systems  within  structures 
National  Electrical  Code,  2011  (first  revision) 


It  may  be  noted  that  some  of  the  above  standards  are  currently  under  revision.  The  revised  version  when  available 
should  also  be  referred. 


Considerable  assistance  has  also  been  drawn  from  following  International  Standards  while  formulating  this  Section: 


IEC  60364-4-41  :  2005 
IEC  60364-4-43  :  2008 
IEC  60364-4-44  :  2007 
IEC  60364-5-51  :  2005 
IEC  60364-5-54  :  201 1 
IEC  60364-7  series 
IEC  61439-1  :  2011 
IEC  61439-2  :  2011 
IEC  61439-6  :  2012 


Low- voltage  electrical  installations  —  Part  4-4 1 :  Protection  for  safety  —  Protection 
against  electric  shock 

Low- voltage  electrical  installations  —  Part  4-43:  Protection  for  safety  —  Protection 
against  overcurrent 

Low- voltage  electrical  installations  —  Part  4-44:  Protection  for  safety  —  Protection 
against  voltage  disturbances  and  electromagnetic  disturbances 
Electrical  installations  of  buildings  —  Part  5-5 1 :  Selection  and  erection  of  electrical 
equipment  —  Common  rules 

Low-voltage  electrical  installations  —  Part  5-54:  Selection  and  erection  of  electrical 
equipment  —  Earthing  arrangements  and  protective  conductors 
Low- voltage  electrical  installations  —  Part  7:  Requirements  for  special  installations 
or  locations 

Low- voltage  switchgear  and  controlgear  assemblies  and  bus  trunking  —  Part  1 : 
General  rules 

Low- voltage  switchgear  and  controlgear  assemblies  and  bus  trunking  —  Part  2:  Power 
switchgear  and  controlgear  assemblies 

Low-voltage  switchgear  and  controlgear  assemblies  and  bus  trunking  —  Part  6: 
Busbar  trunking  systems  (bus ways) 


4 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


All  standards,  whether  given  herein  above  or  cross-referred  to  in  the  main  text  of  this  Section,  are  subject  to 
revision.  The  parties  to  agreement  based  on  this  Section  are  encouraged  to  investigate  the  possibility  of  applying 
the  most  recent  editions  of  the  standards. 

For  the  purpose  of  deciding  whether  a  particular  requirement  of  this  Section  is  complied  with,  the  final  value, 
observed  or  calculated,  expressing  the  result  of  a  test  or  analysis,  shall  be  rounded  off  in  accordance  with  IS  2  :  1 960 
‘Rules  for  rounding  off  numerical  values  ( revised )’.  The  number  of  significant  places  retained  in  the  rounded  off 
value  should  be  the  same  as  that  of  the  specified  value  in  this  Section  of  the  Code. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


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NATIONAL  BUILDING  CODE  OF  INDIA 


PART  8  BUILDING  SERVICES 

Section  2  Electrical  and  Allied  Installations 


1  SCOPE 

This  Code  (Part  8/Section  2)  covers  the  essential 
requirements  for  electrical  installations  in  buildings  to 
ensure  efficient  use  of  electricity  including  safety  from 
fire  and  shock.  This  Section  also  includes  general 
requirements  relating  to  lightning  protection  of 
buildings  and  brief  provisions  on  certain  allied 
installations. 

2  TERMINOLOGY  AND  CONVENTIONAL 
SYMBOLS 

2.1  For  the  purpose  of  this  Section,  the  following 
definitions  shall  apply.  For  definition  of  other  terms, 
reference  may  be  made  to  accepted  standards  [8-2(1)]. 

2.1.1  Accessory  —  A  device,  other  than  current  using 
equipment,  associated  with  such  equipment  or  with  the 
wiring  of  an  installation. 

2.1.2  Apparatus  —  Electrical  apparatus  including  all 
machines,  appliances  and  fittings  in  which  conductors 
are  used  or  of  which  they  form  a  part. 

2.1.3  Appliance  —  An  item  of  current  using  equipment 
other  than  a  luminaire  or  an  independent  motor. 

2.1.4  Back-up  Protection  —  Protection  which  is 
intended  to  operate  when  a  system  fault  is  not  cleared 
or  abnormal  condition  not  detected  in  the  required  time, 
because  of  failure  or  inability  of  other  protection  to 
operate  or  failure  of  appropriate  circuit-breaker  to  trip. 

2.1.5  Barrier  —  A  part  providing  a  defined  degree  of 
protection  against  contact  with  live  parts,  from  any 
usual  direction  of  access. 

2.1.6  Basic  Protection  —  Protection  against  electric 
shock  under  fault-free  condition. 

NOTE  —  For  low  voltage  installations,  systems  and  equipment, 
basic  protection  generally  corresponds  to  protection  against 
direct  contact  that  is  ‘contact  of  persons  or  live  parts’. 

2.1.7  Bonding  Conductor  —  A  protective  conductor 
providing  equipotential  bonding. 

2.1.8  Bonding  Ring  Conductor  (BRC)  — A  bus  earthing 
conductor  in  the  form  of  a  closed  ring. 

NOTE  —  Normally  the  bonding  ring  conductor,  as  part  of  the 
bonding  network,  has  multiple  connections  to  the  common 
bonding  network  (CBN)  that  improves  its  performance. 

2.1.9  Bunched — Cables  are  said  to  be  ‘bunched’  when 
two  or  more  are  contained  within  a  single  conduit,  duct, 
ducting,  or  trunking,  or,  if  not  enclosed,  are  not 
separated  from  each  other. 


2.1.10  Buried  Direct  —  A  cable  laid  in  the  ground  in 
intimate  contact  with  the  soil. 

2.1.11  Busbar  Trunking  System  —  A  type-tested 
assembly,  in  the  form  of  an  enclosed  conductor  system 
comprising  solid  conductors  separated  by  insulating 
materials.  The  assembly  may  consist  of  units  such  as: 

a)  Busbur  trunking  units,  with  or  without  tap-off 
facilities; 

b)  Tap-off  units  where  applicable;  and 

c)  Phase-transposition,  expansion,  building- 
movement,  flexible,  end-feeder  and  adaptor 
units. 

2.1.12  Bypass  Equipotential  Bonding  Conductor  — 
Bonding  conductor  connected  in  parallel  with  the 
screens  of  cables. 

2.1.13  Cable  —  A  length  of  single-insulated  conductor 
(solid  or  stranded),  or  two  or  more  such  conductors, 
each  provided  with  its  own  insulation,  which  are  laid 
up  together.  The  insulated  conductor  or  conductors  may 
or  may  not  be  provided  with  an  overall  mechanical 
protective  covering. 

2.1.14  Cable,  Circuit  Integrity  —  A  cable  which 
continues  to  function,  that  is,  maintains  the  continuity 
of  the  circuit  under  circumstances  of  fire  (against  a 
specified  temperature  and  period  of  the  test). 

NOTE  —  For  circuit  integrity  cable  requirements  reference  may 
be  made  to  accepted  standard  [8-2(2)],  which  prescribes  a  fire 
survival  test  at  750°C  for  3  h. 

2.1.15  Cable,  Flame  Retardant  (FR)  — A  cable  which 
is  flame  retardant  as  per  the  accepted  standard  [8-2(3)] . 

2.1.16  Cable,  Flame  Retardant  Low  Smoke  and 
Halogen  (FR-LSFI)  —  A  cable  which  is  flame  retardant 
and  emits  low  smoke  and  halogen  as  per  the  accepted 
standard  [8-2(3)]. 

2.1.17  Cable,  Flexible  —  A  cable  containing  one  or 
more  cores,  each  formed  of  a  group  of  wires,  the 
diameters  of  the  cores  and  of  the  wires  being  sufficiently 
small  to  afford  flexibility. 

2.1.18  Cable,  Metal-Sheathed  —  An  insulated  cable 
with  a  metal  sheath. 

2.1.19  Cable,  PVC  Sheathed-Insulated  —  A  cable  in 
which  the  insulation  of  the  conductor  is  a 
polyvinylchloride  (PVC)  compound;  with  PVC  sheath 
also  providing  mechanical  protection  to  the  conductor 
core  or  cores  in  the  cable. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


7 


2.1.20  Cable,  Weatherproof —  A  cable  so  constructed 
that  when  installed  in  uncovered  locations,  it  will 
withstand  all  kinds  of  weather  variations  ( see  2.1.186 
for  definition  of  weatherproof). 

2.1.21  Cable,  XLPE  —  A  cable  in  which  the  insulation 
of  the  conductor  is  cross-linked  polythene  and  the 
mechanical  protection  is  provided  for  the  core  or  cores 
by  a  sheath  of  a  polyvinyl  chloride  compound. 

2.1.22  Cable  Armoured  —  A  cable  provided  with  a 
wrapping  of  metal  (usually  in  the  form  of  tape  or  wire) 
serving  as  a  mechanical  protection. 

2.1.23  Cable  Bracket  —  A  cable  support  consisting  of 
single  devices  fixed  to  elements  of  building  or  plant 
construction. 

2.1.24  Cable  Channel  —  An  enclosure  situated  above 
or  in  the  ground,  open  or  ventilated  or  closed,  and 
having  dimensions  which  do  not  permit  the  access  of 
persons  but  allow  access  to  the  conductor  and/or  cables 
throughout  their  length  during  and  after  installation. 

NOTE  —  A  cable  channel  may  or  may  not  form  part  of  the 
building  construction. 

2.1.25  Cable  Cleat — A  component  of  a  support  system 
which  consists  of  elements  spread  at  intervals  along 
the  length  of  the  cable  or  conduits  and  which 
mechanically  retains  the  cable  or  conduit. 

2.1.26  Cable  Coupler  —  A  means  enabling  the 
connection,  at  will,  of  two  flexible  cables.  It  consists 
of  a  connector  and  a  plug. 

2.1.27  Cable  Ducting  —  A  manufactured  enclosure  of 
metal  or  insulating  material,  other  than  conduit  or  cable 
trunking,  intended  for  the  protection  of  cables  which 
are  drawn-in  after  erection  of  the  ducting,  but  which  is 
not  specifically  intended  to  form  part  of  a  building 
structure. 

2.1.28  Cable  Ladder — A  cable  support  occupying  less 
than  10  percent  of  the  plan  area  and  consisting  of  a 
series  of  supporting  elements  rigidly  fixed  to  each  other 
or  to  a  main  supporting  member  or  members. 

2.1.29  Cable  Raceways  —  An  enclosed  channel  of 
metal  or  non-metallic  materials  designed  expressly  for 
holding  wires,  cables  or  busbars,  with  openable/ 
maintainable  construction  having  provision  of 
ventilation.  These  include  electrical  non-metallic 
tubing,  electrical  metallic  tubing,  underfloor  raceways, 
cellular  concrete  floor  raceways,  cellular  metal  floor 
raceways,  surface  raceways  and  wireways. 

2.1.30  Cable  Tray  —  A  cable  support  consisting  of  a 
continuous  base  with  raised  edges  and  no  covering.  A 
cable  tray  is  considered  to  be  non-perforated,  where 
less  than  30  percent  of  the  material  is  removed  from 
the  base. 


2.1.31  Cable  Trunking  —  A  factory  made  closed 
support  and  protection  system  into  which  conductors 
and/or  cables  are  laid  after  removal  of  the  cover. 

2.1.32  Cable  Tunnel  —  An  enclosure  (corridor) 
containing  supporting  structures  for  conductors  and/or 
cables  and  joints  and  whose  dimensions  allow  free 
access  to  persons  throughout  the  entire  length. 

2.1.33  Cartridge  Fuse  Link  —  A  device  comprising  a 
fuse  element  or  several  fuse  elements  connected  in 
parallel  enclosed  in  a  cartridge  usually  filled  with  an 
arc-extinguishing  medium  and  connected  to 
terminations.  The  fuse  link  is  the  part  of  a  fuse  which 
requires  replacing  after  the  fuse  has  operated. 

2.1.34  Ceiling  Rose  —  A  fitting  (usually  used  to  attach 
to  the  ceiling)  designed  for  the  connection  between  the 
electrical  installation  wiring  and  a  flexible  cord  (which 
is  in  turn  connected  to  a  lampholder). 

2.1.35  Circuit  —  An  assembly  of  electrical  equipment 
supplied  from  the  same  origin  and  protected  against 
overcurrent  by  the  same  protective  device(s).  Circuits 
are  categorized  as  follows: 

a)  Category  1  circuit  —  A  circuit  (other  than  a 
fire  alarm  annunciation  or  emergency  lighting 
circuit  and  other  circuits  required  to  work 
during  fire  in  a  building)  operating  at  low 
voltage  and  supplied  directly  from  a  mains 
supply  system. 

b)  Category  2  circuit  —  With  the  exception  of 
Category  3  circuits,  any  circuit  for  extra  low- 
voltage  (ELV)/telecommunication  [for 
example,  radio,  telephone,  sound  distribution, 
building  management  system  (BMS),  public 
address  system  (PAS),  intruder  alarm,  bell  and 
call  and  data  transmission  circuits)]  which  is 
supplied  from  a  safety  source. 

c)  Category  3  circuit  —  A  fire  alarm  circuit  or 
an  emergency  lighting  circuit  and  other 
circuits  required  to  work  during  fire  in  a 
building. 

2.1.36  Circuit  Breaker  —  A  mechanical  switching 
device,  capable  of  making,  carrying  and  breaking 
currents  under  normal  circuit  conditions  and  also  of 
making,  carrying  for  a  specified  time,  and  breaking 
currents  under  specified  abnormal  circuit  conditions 
such  as  those  of  short  circuit. 

NOTE  —  A  circuit  breaker  is  usually  intended  to  operate 
infrequently,  although  some  types  are  suitable  for  frequent 
operation. 

2.1.36.1  Miniature  circuit  breaker  (MCB)  — A  compact 
mechanical  switching  device  capable  of  making, 
carrying  and  breaking  currents  under  normal  circuit 
conditions  and  also  making  and  carrying  currents  for 
specified  times  and  automatically  breaking  currents 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


under  specified  abnormal  circuit  conditions,  such  as 
those  of  overload  and  short  circuits. 

2.1.36.2  Circuit  breaker,  linked  —  A  circuit  breaker, 
the  contacts  of  which  are  so  arranged  as  to  make  or 
break  all  poles  simultaneously  or  in  a  definite  sequence. 

2.1.36.3  Moulded  case  circuit  breaker  (MCCB)  —  A 
circuit  breaker  having  a  supporting  housing  of  moulded 
insulating  material  forming  an  integral  part  of  the  circuit 
breaker. 

2.1.36.4  Air  circuit  breaker  (ACB)  — A  circuit  breaker 
in  which  the  contacts  open  and  close  in  air  at 
atmospheric  pressure. 

2.1.36.5  Residual  current  operated  circuit  breaker  — 
A  mechanical  switching  device  designed  to  make,  carry 
and  break  currents  under  normal  service  conditions  and 
to  cause  the  opening  of  the  contacts  when  the  residual 
current  attains  a  given  value  under  specified  conditions. 

2.1.36.5.1  Residual  current  operated  circuit  breaker 
with  integral  overcurrent  protection  ( RCBO )  —  A 
residual  current  operated  circuit  breaker  designed  to 
perform  the  functions  of  protection  against  overload 
and/or  short-circuit. 

2.1.36.5.2  Residual  current  operated  circuit  breaker 
without  integral  overcurrent  protection  ( RCCB )  —  A 
residual  current  operated  circuit  breaker  not  designed 
to  perform  the  functions  of  protection  against  overload 
and/or  short-circuits. 

NOTE  —  Similar  function  is  provided  by  earth  leakage  circuit 
breaker  (ELCB). 

2.1.37  Circuit,  Final  Sub  —  An  outgoing  circuit 
connected  to  one-way  distribution  board  and  intended 
to  supply  electrical  energy  at  one  or  more  points  to 
current,  using  appliances  without  the  intervention  of  a 
further  distribution  board  other  than  a  one-way  board. 
It  includes  all  branches  and  extensions  derived  from 
that  particular  way  in  the  board. 

2.1.38  Circuit  Integrity  Cable  Support  and  Fixing 
Materials  —  Supports  and  fixing  materials  for 
supporting  circuit  integrity  cable  ( see  2.1.14),  which 
continues  in  service  after  exposure  to  fire  for  a  specified 
duration. 

2.1.39  Compact  Substation  or  Prefabricated 
Substation  —  Prefabricated  and  type-tested  assembly 
which  can  to  be  operated  from  inside  (walk-in  type)  or 
outside  (non-walk-in  type)  comprising  components 
such  as  power  transformer,  high-voltage  switchgear  and 
controlgear,  low-voltage  switchgear  and  controlgear, 
corresponding  interconnections  (cable,  busbar  or  other) 
and-auxiliary  equipment  and  circuits  located  next  to 
each  other,  maintaining  segregation  and  integrity  of 
each  compartment  in  which  they  are  located  along  with 


external  interconnecting  cables,  earthing,  protections, 
etc.  The  components  shall  be  enclosed,  by  either  a 
common  enclosure  or  by  an  assembly  of  enclosures. 

NOTE  —  See  accepted  standard  [8-2(4)]  for  requirements  of 
prefabricated  substation. 

2.1.40  Conductor  of  a  Cable  or  Core — The  conducting 
portion  consisting  of  a  single  wire  or  group  of  wires, 
assembled  together  and  in  contact  with  each  other  or 
connected  in  parallel. 

2.1.41  Conductor,  Aerial  —  Any  conductor  which  is 
supported  by  insulators  above  the  ground  and  is  directly 
exposed  to  the  weather. 

NOTE  —  Following  four  classes  of  aerial  conductors  are 
recognized: 

a)  Bare  aerial  conductors, 

b)  Covered  aerial  conductors, 

c)  Insulated  aerial  conductors,  and 

d)  Weatherproof  neutral-screened  cable. 

2.1.42  Conductor,  Bare  —  A  conductor  not  covered 
with  insulating  material. 

2.1.43  Conductor  Earthed  —  A  conductor  with  no 
provision  for  its  insulation  from  earth. 

2.1.44  Conductor  Insulated — A  conductor  adequately 
covered  with  insulating  material  of  such  quality  and 
thickness  as  to  prevent  danger. 

2.1.45  Conduit  —  A  part  of  a  closed  wiring  system,  a 
circular  or  non-circular  cross-section  for  conductors 
and/or  cables  in  electrical  installations,  allowing  them 
to  be  drawn  in  and/or  replaced.  Conduits  should  be 
sufficiently  closed-jointed  so  that  the  conductors  can 
only  be  drawn  in  and  not  inserted  laterally. 

2.1.46  Connector —  The  part  of  a  cable  coupler  or  of 
an  appliance  coupler  which  is  provided  with  female 
contact  and  is  intended  to  be  attached  to  the  flexible 
cable  connected  to  the  supply. 

2. 1.47  Connector  Box  or  Joint  Box — A  box  forming  a 
part  of  wiring  installation,  provided  to  contain  joints 
in  the  conductors  of  cables  of  the  installations. 

2.1.48  Connector  for  Portable  Appliances  —  A 
combination  of  a  plug  and  socket  arranged  for 
attachment  to  a  portable  electrical  appliance  or  to  a 
flexible  cord. 

2.1.49  Consumer’s  Terminals  —  The  ends  of  the 
electrical  conductors  situated  upon  any  consumer’s 
premises  and  belonging  to  him,  at  which  the  supply  of 
energy  is  delivered  from  the  service  line. 

2.1.50  Continuous  Operating  Voltage  ( Uc )  — 
Maximum  rms  voltage  which  may  be  continuously 
applied  to  a  surge  protection  device’s  mode  of 
protection.  This  is  equal  to  rated  voltage. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


9 


2.1.51  Cord,  Flexible  —  A  flexible  cable  having  a  large 
number  of  (typically  16  or  23  or  46  or  89,  etc)  strands 
of  conductors  of  small  cross-sectional  area.  Two 
flexible  cords  twisted  together  are  known  as  twin 
‘flexible  cord’. 

NOTE  —  Large  number  of  fine  strands  of  wires  for  each 
conductor  makes  the  conductor  capable  of  withstanding 
frequent  bends  thereby  improving  their  flexibility. 

2.1.52  Coreofa  Cable — Asingle conductor ofacable 
with  its  insulation  but  not  including  any  mechanical 
protective  covering. 

2.1.53  Current  Carrying  Capacity  of  a  Conductor  — 
The  maximum  current  which  can  be  carried  by  a 
conductor  under  specified  conditions  without  its  steady 
state  temperature  exceeding  a  specified  value. 

2.1.54  Current  Using  Equipment  —  Equipment  which 
converts  electrical  energy  in  to  another  form  of  energy, 
such  as  light,  heat,  or  motive  power. 

2.1.55  Cut-out  —  Any  appliance  for  automatically 
interrupting  the  transmission  of  energy  through  any 
conductor  when  the  current  rises  above  a  pre¬ 
determined  amount. 

2.1.56  Damp  Situation — A  situation  in  which  moisture 
is  either  permanently  present  or  intermittently  present 
to  such  an  extent  as  likely  to  impair  the  effectiveness 
of  an  installation  conforming  to  the  requirements  for 
ordinary  situations. 

2.1.57  Danger  —  Danger  to  health  or  danger  to  life 
or  limb  from  shock,  burn  or  injury  from  mechanical 
movement  to  persons  (and  livestock  where  present), 
or  from  fire  attendant  upon  the  use  of  electrical 
energy. 

2.1.58  Dead  —  A  portion  of  an  electrical  circuit 
(normally  expected  to  carry  a  voltage)  at  or  near  earth 
potential  or  apparently  disconnected  from  any  live 
system.  A  circuit  apparently  disconnected  from  all 
sources  is  expected  to  be  at  earth  potential;  but 
capacitive  storage  of  charge  in  cables,  capacitors,  etc, 
can  keep  the  electric  circuit  at  a  significant  voltage  (and 
often  dangerous  voltages  from  aspects  of  shock).  Such 
circuits  with  storage  components  will  be  dead  only  on 
connection  to  earth. 

2.1.59  Design  Current  (of  a  Circuit)  —  The  magnitude 
of  the  current  intended  to  be  carried  by  the  circuit  in 
normal  service. 

2.1.60  Direct  Contact —  Contact  of  persons  or  live 
stock  with  live  parts  which  may  result  in  electric 
shock. 

2.1.61  Direct  Earthing  System  — A  system  of  earthing 
in  which  the  parts  of  an  installation  are  so  earthed  as 
specified,  but  are  not  connected  within  the  installation 


to  the  neutral  conductor  of  the  supply  system  or  to  earth 
through  the  trip  coil  of  an  earth  leakage  circuit-breaker. 

2. 1 .62  Disconnector  —  A  mechanical  switching  device 
which,  in  the  open  position,  complies  with  the 
requirements  specified  for  the  isolation  function. 

NOTES 

1  A  disconnector  is  otherwise  known  as  isolator. 

2  A  disconnector  is  capable  of  opening  and  closing  a  circuit 
when  either  a  negligible  current  is  broken  or  made,  or  when  no 
significant  change  in  the  voltage  across  the  terminals  of  each 
pole  of  the  disconnector  occurs.  It  is  also  capable  of  carrying 
currents  under  normal  circuit  conditions  and  carrying  for  a 
specified  time,  current  under  abnormal  conditions,  such  as  those 
of  short-circuit. 

2.1.63  Discrimination  (Over-Current Discrimination)  — 
Coordination  of  the  operating  characteristics  of  two  or 
more  over-current  protective  devices  should  be  such 
that,  on  the  incidence  of  over-currents  within  stated 
limits,  the  device  intended  to  operate  would  be  the 
device  closest  to  the  point  of  fault  or  abnormality,  and 
if  proper  discrimination  is  achieved  within  these  limits, 
only  that  device  closest  should  operate,  while  the  other 
circuit  breakers  upstream  do  not  operate,  thereby 
ensuring  that  there  is  minimum  area  of  power  supply 
which  is  interrupted. 

NOTES 

1  Protective  devices  should  have  discrimination  so  that  only 
the  affected  part  (minimum  section)  of  the  circuit  is  isolated, 
even  though  a  number  of  protective  devices  may  be  in  the  path 
of  the  over  current. 

2  The  electrical  network  requires  the  discrimination  for  all 
the  fault  circuits,  including  overload,  short-circuit,  etc.  The 
downstream  device  should  take  care  of  the  fault  up  to  the 
level  of  ultimate  short-circuit  breaking  capacity,  7CU  of  the 
downstream  breaker  which  should  be  equal  to  the  bus  which 
is  connected. 

3  Distinction  is  made  between  series  discrimination  involving 
different  over-current  protective  devices  passing  substantially 
the  same  over-current  and  network  discrimination  involving 
identical  protective  devices  passing  different  proportions  of  the 
over-current. 

4  Different  types  of  protective  devices  may  have  to  be  used  to 
ensure  effective  discrimination  in  circuits  where  proper  and 
effective  discrimination  is  necessary.  Apart  from  the  built-in 
sensors  and  actuators  in  circuit  breakers,  external  relays 
operating  on  different  parameters,  and  comparison  of 
parameters  between  two  or  more  points  will  have  to  be  used  for 
complex  installations. 

5  See  also  relevant  parts  of  the  accepted  standard  [8-2(5)]. 

2.1 .64  Distance  Area  or  Resistance  Area  (for  an  Earth 
Electrode  Only)  —  The  surface  area  of  ground  (around 
an  earth  electrode)  on  which  a  significant  voltage 
gradient  may  exist. 

2.1.65  Diversity  Factor — A  measure  of  the  probability 
that  a  particular  piece  of  equipment  will  turn  on 
coincidentally  to  another  piece  of  equipment.  For 
aggregate  systems  it  is  defined  as  the  ratio  of  the  sum 
of  the  individual  non-coincident  maximum  loads  of 


10 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


various  subdivisions  of  the  system  to  the  maximum 
demand  of  the  complete  system. 

2.1.66  Duct  —  A  closed  passage  way  formed 
underground  or  in  a  structure  and  intended  to  receive 
one  or  more  cables  which  may  be  drawn  in. 

2.1.67  Ducting  —  See  2.1.27. 

2.1.68  Earth  —  The  conductive  mass  of  the  earth, 
whose  electric  potential  at  any  point  is  conventionally 
taken  as  zero. 

2.1.69  Earth  Continuity  Conductor  —  The  conductor, 
including  any  clamp,  connecting  to  the  earthing  lead 
or  to  each  other,  those  parts  of  an  installation  which 
are  required  to  be  earthed.  It  may  be  in  whole  or  in 
part,  the  metal  conduit  or  the  metal  sheath  or  armour 
of  the  cables,  or  the  special  continuity  conductor  of  a 
cable  or  flexible  cord  incorporating  such  a  conductor. 

2.1.70  Earthed  Concentric  Wiring  —  A  wiring  system 
in  which  one  or  more  insulated  conductors  are 
completely  surrounded  throughout  their  length  by  a 
conductor,  for  example  a  sheath,  which  acts  as  a  PEN 
conductor. 

2.1.71  Earth  Electrode  —  A  conductor  or  group  of 
conductors  in  intimate  contact  with  the  ground  to 
provide  a  low  resistance  path  for  flow  of  current  to 
earth. 

2. 1 .72  Earth  Electrode  Network  —  Part  of  an  earthing 
arrangement  comprising  only  the  earth  electrodes  and 
their  interconnections. 

2.1.73  Earth  Electrode  Resistance  —  The  resistance 
of  an  earth  electrode  to  earth. 

2.1.74  Earth  Fault  —  An  unintended  and  undesirable 
connection  of  phase/neutral  conductor  to  earth.  When 
the  impedance  is  negligible,  the  connection  is  called  a 
dead  earth  fault. 

2.1.75  Earth  Fault  Current — A  current  resulting  from 
a  fault  of  negligible  impedance  between  a  line 
conductor  and  an  exposed  conductive  part  or  a 
protective  conductor. 

2.1.76  Earthing  —  Connection  of  the  exposed 
conductive  parts  of  an  installation  to  the  main  earthing 
terminal  of  that  installation. 

2.1.77  Earthing  Conductor  —  A  protective  conductor 
connecting  the  main  earth  terminal  (or  equipotential 
bonding  conductor  of  an  installation  when  there  is  no 
earth  bus)  to  an  earth  electrode  or  to  other  means  of 
earthing. 

2.1.78  Earthing  Lead — The  final  conductor  by  which 
the  connection  to  the  earth  electrode  is  made. 


2.1.79  Earth  Leakage  Current — A  current  which  flows 
to  earth,  or  to  extraneous  conductive  parts,  in  a  circuit 
which  is  electrically  sound. 

NOTE  —  This  current  may  have  a  capacitive  component 
including  that  resulting  from  the  deliberate  use  of 
capacitors. 

2.1.80  Earthing  Resistance,  Total  —  The  resistance 
between  the  main  earthing  terminal  and  the  earth. 

2.1.81  Electrical  Equipment  (abb:  Equipment)  —  Any 
item  for  such  purposes  as  generation,  conversion, 
transmission,  distribution  or  utilization  of  electrical 
energy,  such  as  machines,  transformers,  apparatus, 
measuring  instruments,  protective  devices,  wiring 
materials,  accessories,  and  appliances. 

2.1.82  Electrically  Independent  Earth  Electrodes  — 
Earth  electrodes  located  at  such  a  distance  from  one 
another  that  the  maximum  current  likely  to  flow  through 
one  of  them  does  not  significantly  affect  the  potential 
of  the  other(s). 

2.1.83  Electrical  Supply  System  for  Life  and  Safety 
Services  —  A  supply  system  intended  to  maintain  the 
operation  of  essential  parts  of  an  electrical  installation 
and  equipment, 

a)  for  health  and  safety  of  persons  and  livestock; 
and 

b)  to  avoid  damage  to  the  environment  and  to 
other  equipment. 

NOTES 

1  The  supply  system  includes  the  source  and  the  circuit(s)  up 
to  the  terminals  of  the  electrical  equipment. 

2  See  also  Part  4  ‘Fire  and  Life  Safety’  of  the  Code  regarding 
emergency  fire  and  life  safety  services. 

2.1.84  Electric  Shock  —  A  dangerous  patho¬ 
physiological  effect  resulting  from  the  passing  of  an 
electric  current  through  a  human  body  or  an  animal. 

2.1.85  Emergency  Switching  —  Rapid  cutting  off  of 
electrical  energy  to  remove  any  hazard  to  persons, 
livestock,  or  property  which  may  occur  unexpectedly. 

2.1.86  Enclosed  Distribution  Board  —  An  enclosure 
containing  bus  bars  with  one  or  more  control  and 
protected  devices  for  the  purpose  of  protecting, 
controlling  or  connecting  more  than  one  outgoing 
circuits  fed  from  one  or  more  incoming  circuits. 

2.1.87  Enclosure  —  A  part  providing  protection  of 
equipment  against  certain  external  influences  and,  in 
any  direction,  protection  against  direct  contact. 

2.1.88  Equipotential  Bonding —  Electrical  connection 
putting  various  exposed  conductive  parts  and 
extraneous  conductive  parts  at  a  substantially  equal 
potential. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


11 


NOTE  —  In  a  building  installation  equipotential  bonding 
conductors  shall  interconnect  the  following  conductive  parts: 

a)  Protective  conductor, 

b)  Earth  continuity  conductor,  and 

c)  Risers  of  air  conditioning  system  and  heating  systems 
(if  any). 

2.1.89  Exposed  Conductive  Part  —  A  conductive  part 
of  electrical  equipment,  which  can  be  touched  and 
which  is  not  normally  live,  but  which  may  become  live 
under  fault  conditions. 

2.1.90  Exposed  Metal  —  All  metal  parts  of  an 
installation  which  are  easily  accessible  other  than, 

a)  parts  separated  from  live  parts  by  double 
insulation; 

b)  metal  name-plates,  screw  heads,  covers,  or 
plates,  which  are  supported  on,  or  attached, 
or  connected  to  substantial  non-conducting 
material  only  in  such  a  manner  that  they  do 
not  become  alive  in  the  event  of  failure  of 
insulation  of  live  parts  and  whose  means  of 
fixing  do  not  come  in  contact  with  any  internal 
metal;  and 

c)  parts  which  are  separated  from  live  parts  by 
other  metal  parts  which  are  themselves  earthed 
or  have  double  insulation. 

2.1.91  External  Influence  —  Any  influence  external  to 
an  electrical  installation  which  affects  the  design  and 
safe  operation  of  that  installation. 

2.1.92  Extraneous  Conductive  Part  —  A  conductive 
part  not  forming  part  of  the  electrical  installation  and 
liable  to  introduce  a  potential,  generally  the  earth 
potential. 

2.1.93  Fault  —  A  circuit  condition  in  which  current 
flows  through  an  abnormal  or  unintended  path.  This 
may  result  from  an  insulation  failure  or  a  bridging  of 
insulation.  Conventionally  the  impedance  between  live 
conductors  or  between  lives  conductors  and  exposed 
or  extraneous  conductive  parts  at  the  fault  position  is 
considered  negligible. 

2.1.94  Fault  Current — A  current  resulting  from  a  fault. 

2.1.95  Fault  Protection  —  Protection  against  electric 
shock  under  single  fault  conditions. 

NOTE  —  For  low  voltage  installation,  system’s  and  equipment’s 
fault  protection  generally  corresponds  to  protection  against 
indirect  contact,  mainly  with  regards  to  failure  of  basic 
insulation.  Indirect  contact  is  ‘contact  of  persons  or  livestock 
with  exposed-conductive  parts  which  have  become  live  under 
fault  conditions’. 

2.1.96  Final  Circuit  —  A  circuit  connected  directly 
to  current  using  equipment,  or  to  socket  outlets  or 
other  outlet  points  for  the  connection  of  such 
equipment. 


2.1.97  Fire  Survival  Distribution  Board  —  A 
distribution  board  which  continues  in  service  after 
exposure  to  fire  to  the  required  system  rating. 

2.1.98  Fitting,  Lighting  —  A  device  for  supporting  or 
containing  a  lamp  or  lamps  [for  example,  fluorescent  or 
incandescent  or  halogen  or  compact  fluorescent  lamp 
(CFL)  or  light  emitting  diode  (LED)]  together  with  any 
holder,  shade,  or  reflector,  for  example,  a  bracket,  a 
pendant  with  ceiling  rose,  an  electrolier,  or  a  portable  unit. 

2.1.99  Fixed  Equipment  —  Equipment  fastened  to  a 
support  or  otherwise  secured. 

2.1.100  Flameproof  Enclosure  —  An  enclosure  which 
will  withstand  without  injury  any  explosion  of 
inflammable  gas  that  may  occur  within  it  under  practical 
conditions  of  operation  within  the  rating  of  the 
apparatus  (and  recognized  overloads,  if  any,  associated 
therewith)  and  will  prevent  the  transmission  of  flame 
which  may  ignite  any  inflammable  gas  that  may  be 
present  in  the  surrounding  atmosphere. 

NOTES 

1  Hazardous  areas  are  classified  into  different  zones,  depending 
upon  the  extent  to  which  an  explosive  atmosphere  may  exist  at 
that  place.  In  such  areas,  flame  proof  switchgear,  fittings, 
accessories,  have  to  be  used/installed  in  flameproof  enclosure. 

2  An  electrical  apparatus  is  not  considered  as  flameproof  unless 
it  complies  with  the  appropriate  statutory  regulations. 

3  Other  types  of  fittings  are  also  in  vogue  in  wiring  installations, 
for  example,  ‘increased  safety’. 

2.1.101  Functional  Earthing  —  Connection  to  earth 
necessary  for  proper  functioning  of  electrical 
equipment. 

2.1.102  Fuse  —  A  device  which,  by  melting  of  one  or 
more  of  its  specially  designed  and  proportioned 
components,  opens  the  circuit  in  which  it  is  inserted  by 
breaking  the  current  when  this  exceeds  a  given  value 
for  a  sufficient  time.  The  fuse  comprises  all  the  parts 
that  form  the  complete  device. 

2.1.103  Fuse  Carrier  —  The  movable  part  of  a  fuse 
designed  to  carry  a  fuse  link. 

2.1.104  Fuse  Element  —  A  part  of  a  fuse  designed  to 
melt  when  the  fuse  operates. 

2.1.105  Fuse  Link  —  Apart  of  fuse,  including  the  fuse 
element(s),  which  requires  replacement  by  a  new  or 
renewable  fuse  link  after  the  fuse  has  operated  and 
before  the  fuse  is  put  back  into  service. 

2.1.106  Hand-Held  Equipment  —  Portable  equipment 
intended  to  be  held  in  the  hand  during  normal  use,  in 
which  the  motor,  if  any,  forms  an  integral  part  of  the 
equipment. 

NOTE  —  A  hand  held  equipment  is  an  item  of  equipment,  the 
functioning  of  which  requires  constant  manual  support  or 
guidance. 


12 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


2.1.107  Harmonics  (Current  and  Voltage)  —  All 
alternating  current  which  is  not  absolutely  sinusoidal 
is  made  up  of  a  fundamental  and  a  certain  number  of 
current  and  voltage  harmonics  [multiples  of  50  Hz 
(basic  frequency)]  which  are  the  cause  of  its 
deformation  (distortion)  when  compared  to  the 
theoretical  sine-wave. 

2.1.108  Hazardous  Live  Part  —  A  live  part  which  can 
give,  under  certain  condition  of  external  influence,  an 
electric  shock. 

2.1.109  Impulse  Current  —  A  parameter  used  for  the 
classification  test  for  SPDs;  it  is  defined  by  three 
elements,  a  current  peak  value,  a  charge  Q  and  a  specific 
energy  W/R. 

2.1.110  Impulse  Withstand  Voltage  —  The  highest  peak 
value  of  impulse  voltage  of  prescribed  form  and  polarity 
which  does  not  cause  breakdown  of  insulation  under 
specified  condition. 

2.1.111  Indirect  Contact  —  Contact  of  persons  or 
livestock  with  exposed  conductive  parts  made  live  by 
a  fault  and  which  may  result  in  electric  shock. 

2.1.112  Industrial  Plugs  and  Sockets  —  Plugs  and 
socket-outlets,  cable  couplers  and  appliance  couplers, 
primarily  intended  for  industrial  use,  either  indoors  or 
outdoors. 

NOTE  —  For  the  purpose  of  this  Code,  industrial  plugs  and 
sockets  conforming  to  1S/1EC  60309-1:2002  ‘Plugs,  socket- 
outlets  and  couplers  for  industrial  purposes  —  Part  1 :  General 
requirements’;  and  1S/1EC  60309-2:2002  ‘Plugs,  socket-outlets 
and  couplers  for  industrial  purposes  —  Part  2:  Dimensional 
Interchangeability  Requirements  for  Pin  and  Contact  Tube 
Accessories’  shall  be  used  for  industrial  purpose. 

2.1.113  Inflammable  Material  —  A  material  capable 
of  being  easily  ignited. 

2.1.114  Installation  (Electrical)  —  An  assembly  of 
associated  electrical  equipment  to  fulfill  a  specific 
purpose  or  purposes  and  having  coordinated 
characteristics. 

2.1.115  Insulated  —  Insulated  shall  mean  separated 
from  adjacent  conducting  material  or  protected  from 
personal  contact  by  a  non-conducting  substance  or  an 
air  space,  in  either  case  offering  permanently  sufficient 
resistance  to  the  passage  of  current  or  to  disruptive 
discharges  through  or  over  the  surface  of  the  substance 
or  space,  to  obviate  danger  or  shock  or  injurious  leakage 
of  current. 

2.1.116  Insulation  —  Suitable  non-conducting  material, 
enclosing,  surrounding  or  supporting  a  conductor. 

2.1.116.1  Insulation,  basic  —  Insulation  applied  to  live 
parts  to  provide  basic  protection  against  electric  shock 
and  which  does  not  necessarily  include  insulation  used 
exclusively  for  functional  purposes. 


2.1.116.2  Insulation,  double  —  Insulation  comprising 
both  basic  and  supplementary  insulation. 

NOTE  —  Double  insulation  for  small  hand  held  equipment 
allows  them  to  be  used  without  a  safety  earth  connection, 
without  shock  risk  such  hand  held  equipment. 

2.1.116.3  Insulation,  reinforced  —  Single  insulation 
applied  to  live  parts,  which  provides  a  degree  of 
protection  against  electric  shock  equivalent  to  double 
insulation  under  the  conditions  specified  in  the  relevant 
standard. 

NOTE  —  The  term  ‘single  insulation’  does  not  imply  that  the 
insulation  is  a  homogeneous  piece.  It  may  comprise  several 
layers  which  cannot  be  tested  singly  as  supplementary  or  basic 
insulation. 

2.1.116.4  Insulation,  supplementary  —  Independent 
insulation  applied  in  addition  to  basic  insulation  in  order 
to  provide  protection  against  electric  shock  in  the  event 
of  a  failure  of  basic  insulation. 

2.1.117  Isolation  —  Cutting  off  an  electrical 
installation,  a  circuit,  or  an  item  of  equipment  from 
every  source  of  electrical  energy. 

2.1.118  Isolator  —  A  mechanical  switching  device 
which,  in  the  open  position,  complies  with  the 
requirements  specified  for  the  isolating  function.  An 
isolator  is  otherwise  known  as  a  disconnector. 

2.1.119  Junction  Box  —  A  box  forming  a  part  of  wiring 
installation,  intended  to  conceal  electrical  connections 
and  joints  of  conductors/  cables  in  order  to  protect  the 
connection  from  external  influences  such  as  direct 
contact,  dust,  water,  moisture,  UV  radiation,  etc, 
depending  upon  the  protection  requirement  of  the  space 
or  utility. 

2.1.120  LEMP  Protection  Measures  (SPM)  — 
Measures  taken  to  protect  internal  systems  against  the 
effects  of  LEMR 

2.1.121  Lightning  Electromagnetic  Impulse  (LEMP)  — 
All  electromagnetic  effects  of  lightning  current  via 
resistive,  inductive  and  capacitive  coupling  that  create 
surges  and  radiated  electromagnetic  fields. 

2.1.122  Lightning  Protection  —  Complete  system  for 
protection  of  structures  against  lightning,  including  their 
internal  systems  and  contents,  as  well  as  persons,  in 
general  consisting  of  an  LPS  and  SPM. 

2.1.123  Lightning  Protection  Level  (LPL)  —  A  number 
related  to  a  set  of  lightning  current  parameters  values 
relevant  to  the  probability  that  the  associated  maximum 
and  minimum  design  values  will  not  be  exceeded  in 
naturally  occurring  lightning. 

NOTE  —  Lightning  protection  level  is  used  to  design  protection 
measures  according  to  the  relevant  set  of  lightning  current 
parameters. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


13 


2.1.124  Lightning  Protection  System  (LPS)  — 
Complete  system  used  to  reduce  physical  damage  due 
to  lightning  flashes  to  a  structure. 

2.1.124.1  External  lightning  protection  system  —  Part 
of  the  LPS  consisting  of  an  air-termination  system,  a 
down-conductor  system  and  an  earth-termination 
system. 

2.1.124.2  Internal  lightning  protection  system  —  Part 
of  the  LPS  consisting  of  lightning  equipotential  bonding 
and/or  electrical  insulation  of  external  LPS. 

2.1.125  Lightning  Protection  Zone  —  Zone  where  the 
lightning  electromagnetic  environment  is  defined. 

2.1.126  Live  or  Alive  —  Electrically  charged  so  as  to 
have  a  potential  different  from  that  of  earth. 

2.1.127  Locations,  Industrial — Locations  where  tools 
and  machinery  requiring  electrical  wiring  are  installed 
for  manufacture  or  repair. 

2.1.128  Locations,  Non-Industrial — Locations  other 
than  industrial  locations,  and  shall  include  residences, 
offices,  shops,  showrooms,  stores  and  similar  premises 
requiring  electrical  wiring  for  lighting,  or  similar 
purposes. 

2.1.129  Leakage  Current  —  Electric  current  in  an 
unwanted  conductive  path  under  normal  operating 
conditions. 

2.1.130  Line  Conductor  —  A  conductor  of  an  a.c. 
system  for  the  transmission  of  electrical  energy  other 
than  a  neutral  conductor  or  a  PEN  conductor.  This  also 
means  the  equivalent  conductor  of  a  d.c.  system  unless 
otherwise  specified  in  this  Code. 

2.1.131  Live  Part  —  A  conductor  or  conductive  part 
intended  to  be  energised  in  normal  use  including  a 
neutral  conductor  but,  by  convention,  not  a  PEN 
conductor. 

2.1.132  Low  Voltage  Switchgear  and  Controlgear 
Assembly  —  A  combination  of  one  or  more  low  voltage 
switching  devices  together  with  associated  control, 
measuring,  signalling,  protective,  regulating  equipment, 
etc,  completely  assembled  under  the  responsibility  of 
the  manufacturer  with  all  the  internal  electrical  and 
mechanical  interconnections  and  structural  parts.  The 
components  of  the  assembly  may  be  electromechanical 
or  electronic. 

2.1.133  Luminaire  —  Equipment  which  distributes, 
filters  or  transforms  the  light  from  one  or  more  lamps, 
and  which  includes  any  parts  necessary  for  supporting, 
fixing  and  protecting  the  lamps,  but  not  the  lamps 
themselves,  and,  where  necessary,  circuit  auxiliaries 
together  with  the  means  for  connecting  them  to  the 
supply. 


NOTE  —  For  the  purposes  of  this  Code  a  batten  lampholder, 
or  a  lampholder  suspended  by  flexible  cord,  is  a  luminaire. 

2.1.134  Main  Earthing  Terminal  —  The  terminal  or 
bar  which  is  the  equipotential  bonding  conductor  of 
protective  conductors,  and  conductors  for  functional 
earthing,  if  any,  to  the  means  of  earthing. 

2.1.135  Meshed  Bonding  Network  ( MESH-BN)  — 
Bonding  network  in  which  all  associated  equipment 
frames,  racks  and  cabinets  and  usually  the  d.c.  power 
return  conductor  are  bonded  together  as  well  as  at 
multiple  points  to  the  CBN  and  may  have  the  form  of  a 
mesh. 

2.1.136  Mobile  Equipment  —  Electrical  equipment 
which  is  moved  while  in  operation  or  which  can  be 
easily  moved  from  one  place  to  another  while  connected 
to  the  supply. 

2.1.137  Monitoring  —  Observation  of  the  operation  of 
a  system  or  part  of  a  system  to  verify  correct  functioning 
or  detect  incorrect  functioning  by  measuring  system 
variables  and  comparing  the  measured  value  with  the 
specified  value. 

2.1.138  Multiple  Earthed  Neutral  System  —  A  system 
of  earthing  in  which  the  parts  of  an  installation  specified 
to  be  earthed  are  connected  to  the  general  mass  of  earth 
and,  in  addition,  are  connected  within  the  installation 
to  the  neutral  conductor  of  the  supply  system. 

2.1.139  Neutral  Conductor —  Includes  the  conductor 
of  a  three-phase  four-wire  system;  the  conductor  of  a 
single-phase  or  d.c.  installation,  which  is  earthed  by 
the  supply  undertaking  (or  otherwise  at  the  source  of 
the  supply),  and  the  middle  wire  or  common  return 
conductor  of  a  three-wire  d.c.  or  single-phase  a.c. 
system. 

2.1.140  Origin  of  an  Electrical  Installation  —  The 
point  at  which  electrical  energy  is  delivered  to  an 
installation. 

NOTE  —  An  electrical  installation  may  have  more  than  one 
origin. 

2.1.141  Overcurrent  —  A  current  exceeding  the  rated 
value.  For  conductors  the  rated  value  is  the  current 
carrying  capacity. 

2.1.142  Overload  Current  (of  a  Circuit)  —  An 
overcurrent  occurring  in  a  circuit  in  the  absence  of  an 
electrical  fault. 

2. 1 . 143  PEN  Conductor — A  conductor  combining  the 
functions  of  both  protective  conductor  and  neutral 
conductor. 

2.1.144  Phase  Conductor  —  See  2.1.130. 

2.1.145  Plug  —  A  device,  provided  with  contact  pins, 
which  is  intended  to  be  attached  to  a  flexible  cable, 


14 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


and  which  can  be  engaged  with  a  socket  outlet  or  with 
a  connector. 

2.1.146  Point  (in  Wiring)  —  A  termination  of  the  fixed 
wiring  intended  for  the  connection  of  current  using 
equipment. 

2.1.147  Portable  Equipment  —  Equipment  which  is 
moved  while  in  operation  or  which  can  easily  be  moved 
from  one  place  to  another  while  connected  to  the  supply. 

2.1.148  Protection,  Ingress  —  The  degree  of  protection 
against  intrusions  (body  parts  such  as  hands  and 
fingers),  dust,  accidental  contact  and  water. 

NOTE  —  The  classification  of  degrees  of  ingress  protection 
provided  by  enclosures  for  electrical  equipment  shall  be  as  per 
the  accepted  standard  [8-2(6)]. 

2.1.149  Protection ,  Mechanical  Impact —  The  degrees 
of  protection  provided  by  enclosures  for  electrical 
equipment  against  external  mechanical  impacts. 

NOTE  —  The  classification  of  degrees  of  protection  against 
mechanical  impact  provided  by  enclosures  for  electrical 
equipment  shall  be  as  per  IEC  62262:2002  ‘Degrees  of 
protection  provided  by  enclosures  for  electrical  equipment 
against  external  mechanical  impacts  (IK  code)’. 

2.1.150  Prospective  Fault  Current  (7pf)  —  The  value 
of  overcurrent  at  a  given  point  in  a  circuit  resulting 
from  a  fault  of  negligible  impedance  between  live 
conductor  having  a  difference  of  potential  under  normal 
operating  conditions,  or  between  a  live  conductor  and 
an  exposed-conductive  part. 

2.1.151  Protective  Conductor — A  conductor  used  for 
some  measures  of  protection  against  electric  shock  and 
intended  for  connecting  together  any  of  the  following 
parts: 

a)  Exposed  conductive  parts, 

b)  Extraneous  conductive  parts, 

c)  Main  earthing  terminal,  and 

d)  Earthed  point  of  the  source,  or  an  artificial 
neutral. 

2.1.152  Protective  Conductor  Current  —  Electric 
current  appearing  in  a  protective  conductor,  such  as 
leakage  current  or  electric  current  resulting  from  an 
insulation  fault. 

2.1.153  Protective  Earthing  —  Earthing  of  a  point  or 
points  in  a  system  or  in  equivalent  for  the  purpose  of 
safety. 

2.1.154  Protective  Separation  —  Separation  of  one 
electric  circuit  from  another  by  means  of, 

a)  double  insulation; 

b)  basic  insulation  and  electrically  protective 
screening  (shielding);  or 

c)  reinforced  insulation. 


2.1.155  Rated  Current  —  Value  of  current  used  for 
specification  purposes,  established  for  a  specified  set 
of  operating  conditions  of  a  component,  device, 
equipment  or  system. 

2.1.156  Rated  Impulse  Withstand  Voltage  Level  (t/w)  — 
The  level  of  impulse  withstand  voltage  assigned  by  the 
manufacturer  to  the  equipment,  or  to  part  of  it, 
characterizing  the  specified  withstand  capability  of  its 
insulation  against  overvoltage. 

2.1.157  Residual  Current —  The  algebraic  sum  of  the 
instantaneous  values  of  current  flowing  through  all  live 
conductors  of  a  circuit  at  a  point  of  the  electrical 
installation. 

2.1.158  Residual  Current  Device  (RCD)  —  A 
mechanical  switching  device  or  association  of  devices 
intended  to  cause  the  opening  of  the  contacts  when  the 
residual  current  attains  a  given  value  under  specified 
conditions. 

2.1.159  Residual  Operating  Current  —  Residual 
current  which  causes  the  residual  current  device  to 
operate  under  specified  conditions. 

2.1.160  Service  —  The  conductors  and  equipment 
required  for  delivering  energy  from  the  electric  supply 
system  to  the  wiring  system  of  the  premises  served. 

2.1.161  Shock  Current  A  current  passing  through  the 
body  of  a  person  or  an  animal  and  having  characteristics 
likely  to  cause  dangerous  patho-physiological  effects. 

2.1.162  Short-Circuit  Current  —  An  overcurrent 
resulting  from  a  fault  of  negligible  impedance  between 
live  conductors  having  a  difference  in  potential  under 
normal  operating  conditions. 

2.1.163  Space  Factor  —  The  ratio  (expressed  as  a 
percentage)  of  the  sum  of  the  overall  cross-sectional 
areas  of  cables  (including  insulation  and  sheath)  to  the 
internal  cross-sectional  area  of  the  conduit  or  other 
cable  enclosure  in  which  they  are  installed.  The 
effective  overall  cross-sectional  area  of  a  non-circular 
cable  is  taken  as  that  of  a  circle  of  diameter  equal  to 
the  major  axis  of  the  cable. 

2.1.164  Standby  Supply  System  —  A  system  intended 
to  maintain  supply  to  the  installation  or  part  thereof,  in 
case  of  interruption  of  the  normal  supply,  for  reasons 
other  than  safety  of  persons. 

NOTE  —  Standby  supplies  are  necessary,  for  example,  to  avoid 
interruption  of  continuous  industrial  processes  or  data 
processing. 

2.1.165  Stationary  Equipment  —  Either  fixed 
equipment  or  equipment  not  provided  with  a  carrying 
handle  and  having  such  a  mass  that  it  cannot  easily  be 
moved. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


15 


2.1.166  Step  Voltage  —  The  potential  difference 
between  two  points  on  the  earth’s  surface,  separated 
by  distance  of  one  pace,  that  will  be  assumed  to  be  one 
metre  in  the  direction  of  maximum  potential  gradient. 

2.1.167  Socket-Outlet  —  A  device,  provided  with 
female  contacts,  which  is  intended  to  be  installed  with 
the  fixed  wiring,  and  intended  to  receive  a  plug. 

NOTE  —  A  luminaire  track  system  is  not  regarded  as  a  socket- 
outlet  system. 

2.1.168  Surge  —  A  transient  created  by  LEMP  that 
appears  as  an  overvoltage  and/or  an  overcurrent. 

2.1.169  Surge  Protective  Devices  ( SPD )  —  A  device 
intended  to  limit  transient  overvoltages  and  divert  surge 
currents.  It  contains  at  least  one  non-linear  component. 

2.1.170  Switch  —  A  mechanical  switching  device 
capable  of  making,  carrying  and  breaking  current  under 
normal  circuit  conditions,  which  may  include  specified 
operating  overload  conditions;  and  also  of  carrying  for 
a  specified  time  currents  under  specified  abnormal 
circuit  conditions,  such  as  those  of  short  circuit. 

NOTE  —  A  switch  may  also  be  capable  of  making,  but  not 
breaking,  short-circuit  currents. 

2.1.171  Switchboard  —  An  assembly  of  switchgear 
with  or  without  instruments,  but  the  term  does  not  apply 
to  a  group  of  local  switches  in  a  final  circuit. 

NOTE  —  The  term  ‘switchboard’  includes  a  distribution  board. 

2.1.172  Switch  Disconnector  —  A  switch  which,  in  the 
open  position,  satisfies  the  isolating  requirements 
specified  for  a  disconnector. 

NOTE  —  A  switch  disconnector  is  otherwise  known  as  an 
isolating  switch. 

2.1.173  Switch  Disconnector  Fuse  —  A  composite  unit, 
comprising  a  switch  with  the  fuse  contained  in  or 
mounted  on  the  moving  member  of  the  switch. 

2.1.174  Switch,  Linked  —  A  switch,  the  contacts  of 
which  are  so  arranged  as  to  make  or  break  all  poles 
simultaneously  or  in  a  definite  sequence. 

2.1.175  Switchgear  —  An  assembly  of  main  and 
auxiliary  switching  apparatus  for  operation,  regulation, 
protection  or  other  control  of  electrical  installations. 

2.1.176  System  ( Electrial )  —  An  electrical  system 
consisting  of  a  single  source  or  multiple  sources  running 
in  parallel  of  electrical  energy  and  an  installation.  Types 
of  system  are  identified  as  follows,  depending  upon 
the  relationship  of  the  source,  and  of  exposed- 
conductive  parts  of  the  installation,  to  earth: 

a)  TN  system  —  A  system  having  one  or  more 
points  of  the  source  of  energy  directly  earthed, 
the  exposed  conductive-parts  of  the 
installation  being  connected  to  that  point  by 


protective  conductors. 

b)  TN-C system  —  A  system  in  which  neutral  and 
protective  conductors  are  combined  in  a  single 
conductor  throughout  the  system. 

c)  TN-S  system  —  A  system  having  separate 
neutral  and  protective  conductor  throughout 
the  system. 

d)  TN-C-S  system  —  A  system  in  which  neutral 
and  protective  conductors  are  combined  in  a 
single  conductor  in  part  of  the  system. 

e)  TT  system  —  A  system  having  one  point  of 
the  source  of  energy  directly  earthed,  the 
exposed-conductive-parts  of  the  installation 
being  connected  to  the  earth  electrodes 
electrically  independent  of  the  earth  electrodes 
of  the  source. 

f)  IT  system  —  A  system  having  no  direct 
connection  between  live  parts  and  earth,  the 
exposed-conductive-parts  of  the  electrical 
installation  being  earthed. 

2.1.177  Touch  Voltage  —  The  potential  difference 
between  the  ground  potential  rise  (GPR)  of  a  grounded 
metallic  structure  and  the  surface  potential  at  the  point 
where  a  person  could  be  standing  while  at  the  same 
time  having  a  hand  in  contact  with  the  grounded  metallic 
structure.  Touch  voltage  measurements  can  be  ‘open 
circuit’  (without  the  equivalent  body  resistance  included 
in  the  measurement  circuit)  or  ‘closed  circuit’  (with  the 
equivalent  body  resistance  included  in  the  measurement 
circuit)  voltage  by  which  an  installation  or  part  of  an 
installation  is  designated. 

2.1.178  Usable  Wall  Space  —  All  portions  of  a  wall, 
except  that  occupied  by  a  door  in  its  normal  open 
position,  or  occupied  by  a  fire  place  opening,  but 
excluding  wall  spaces  which  are  less  than  1  m  in  extent 
measured  along  the  wall  at  the  floor  line. 

2.1.179  Utility  Building — A  standalone  separate  single 
or  two  storied  service  building  structure  outside  the 
main  building  structure  meant  for  only  accommodating 
services’  spaces,  such  as  electric  substation,  diesel 
generator  plant  room,  a.c.  plant  room,  plumbing  plant 
room,  sewerage  treatment  plant,  medical  gases, 
electrical  and  mechanical  maintenance  rooms.  Such 
buildings  do  not  have  any  permanent  occupancy  other 
than  by  personnel  on  duty. 

2.1.180  Voltage,  Nominal  (of  an  Installation)  — 
Voltage  by  which  an  installation  or  part  of  an  installation 
is  designated. 

2.1.181  Voltage,  Extra  Low  (ELV)  — The  voltage  which 
does  not  normally  exceed  50  V. 

2.1.182  Voltage,  Low  ( LV)  —  The  voltage  which 
normally  exceeds  50  V  but  does  not  normally  exceed 
250  V. 


16 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


2.1.183  Voltage,  Medium  ( MV)  —  The  voltage  which 
normally  exceeds  250  V  but  does  not  exceed  650  V. 

2.1.184  Voltage,  High  (HV)  —  The  voltage  which 
normally  exceeds  650  V  but  less  than  or  equal  to  33  kV. 

2.1.185  Voltage,  Extra  High  (EHV)  —  The  voltage, 
which  normally  exceeds  33  kV. 

2.1.186  Weatherproof — Accessories,  lighting  fittings, 
current-using  appliances  and  cables  are  said  to  be  of 
the  weatherproof  type  with  ingress  protection  according 
to  the  application,  if  they  are  so  constructed  that  when 
installed  in  open  situation  they  will  withstand  the  effects 
of  rain,  snow,  dust  and  temperature  variations. 

2.2  Conventional  Symbols 

The  architectural  symbols  that  are  to  be  used  in  all 
drawings,  wiring  plans,  etc,  for  electrical  installations 
in  buildings  shall  be  as  given  in  Annex  A. 

For  other  graphical  symbols  used  in  electrotechnology, 
reference  may  be  made  to  good  practice  [8-2(1)]. 

3  GENERAL  REQUIREMENTS 

3.1  Conformity  with  The  Electricity  Act,  2003  and 
Central  Electricity  Authority  (Measures  Relating  to 
Safety  and  Electric  Supply)  Regulations,  2010  as 
Amended  Up-to-Date 

The  installation  shall  generally  be  carried  out  in 
conformity  with  the  requirements  of  The  Electricity  Act, 
2003  as  amended  up-to-date  and  the  Central  Electricity 
Authority  (Measures  Relating  to  Safety  and  Electric 
Supply)  Regulations,  2010  framed  thereunder  and  as 
amended  from  time-to-time;  and  also  the  relevant 
regulations  of  the  Electric  Supply  Authority  concerned 
as  amended  from  time-to-time.  Extracts  from  the 
Central  Electricity  Authority  (Measures  Relating  to 
Safety  and  Electric  Supply)  Regulations,  2010  (as 
amended  in  2015),  referred  to  in  this  Section,  are  given 
in  Annex  B. 

3.2  Materials 

All  materials,  fittings,  appliances,  etc,  used  in  electrical 
and  allied  installations,  shall  conform  to  Part  5 
‘Building  Materials’  of  the  Code  and  other  concerned 
Indian  Standards. 

3.3  Coordination  with  Local  Supply  Authority 

a)  In  all  cases,  that  is,  whether  the  proposed 
electrical  work  is  a  new  installation  or 
extension  of  an  existing  one,  or  a  modification 
involving  major  changes,  the  electricity  supply 
undertaking  shall  be  consulted  about  the 
feasibility,  etc,  at  an  early  date.  The  wattage 
per  square  metre  and  permissible  diversity 
consideration  shall  be  defined  as  per  the  type 


of  building  (residential,  commercial, 
mercantile,  industrial,  retail,  convention, 
exhibition,  hotel,  hospital,  institution,  flatted 
factory,  group  housing,  etc).  The  wattage  per 
square  feet  shall  be  defined  considering 
probable  loads  as  per  city  grading  such  that 
future  loading  into  the  development  is 
accounted. 

b)  Addition  to  an  Installation  —  An  addition, 
temporary  or  permanent,  shall  not  be  made  to 
the  authorized  load  of  an  existing  installation, 
until  it  has  been  definitely  ascertained  that  the 
current  carrying  capacity  and  the  condition  of 
existing  accessories,  conductors,  switches,  etc, 
affected,  including  those  of  the  supply 
authority  are  adequate  for  the  increased  load. 
The  size  of  the  cable/conductor  shall  be 
suitably  selected  on  the  basis  of  the  ratings  of 
the  protective  devices.  Ratings  of  protective 
devices  and  their  types  shall  be  based  on  the 
installed  load,  switching  characteristics  and 
power  factor. 

Load  assessment  and  application  of  suitable  diversity 
factor  to  estimate  the  full  load  current  shall  be  made  as 
a  first  step.  This  should  be  done  for  every  circuit, 
submain  and  feeder.  Power  factor,  harmonics 
(see  5.3. 6. 6)  and  efficiency  of  loads  shall  also  be 
considered.  Diversity  factor  assumed  shall  be  based 
on  one’s  own  experience  or  as  per  table  under  4.2.2.2. 
Allowance  should  be  made  for  about  1 5  percent  to  20 
percent  for  extension  in  near  future.  The  wiring  system 
should  be  adopted  taking  into  account  the 
environmental  requirements  and  hazards,  if  any  in  the 
building.  The  sizes  of  wiring  cables  are  decided  not 
merely  to  carry  the  load  currents,  but  also  to  withstand 
thermal  effects  of  likely  overcurrents,  short  circuit  and 
also  to  ensure  acceptance  level  of  voltage  drop. 

3.4  Power  Factor  Improvement  in  Consumers’ 
Installation 

3.4.1  Conditions  of  supply  of  electricity  boards  or 
licensees  stipulate  the  lower  limit  of  power  factor  which 
is  generally  0.90  or  better. 

3.4.2  Principal  causes  of  low  power  factor  are  many. 
For  guidance  to  the  consumers  of  electric  energy  who 
take  supply  at  low  and  medium  voltages  for 
improvement  of  power  factor,  reference  shall  be  made 
to  good  practice  [8-2(7)]. 

3.5  Execution  of  Work 

Unless  otherwise  exempted  under  the  appropriate 
regulation  of  the  CEA  (Measures  relating  to  Safety  and 
Electricity  Supply)  Regulations ,  2010  as  amended  from 
time-to-time,  the  work  of  electrical  installations  shall 
be  carried  out  by  a  licensed  electrical  contractor  and 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


17 


under  the  direct  supervision  of  a  person  holding  a 
certificate  of  competency  and  by  persons  holding  a  valid 
permit  issued  and  recognized  by  any  State  government. 

3.6  Safety  procedures  and  practices  shall  be  kept  in  view 
during  execution  of  the  work  in  accordance  with  good 
practice  [8-2(8)]. 

3.7  Safety  provisions  given  in  Part  4  ‘Fire  and  Life 
Safety’  of  the  Code  shall  be  followed. 

4  PLANNING  OF  ELECTRICAL  INSTALLA¬ 
TIONS 

4.1  General 

The  design  and  planning  of  an  electrical  wiring 
installation  involve  consideration  of  all  prevailing 
conditions,  and  is  usually  influenced  by  the  type  and 
requirements  of  the  consumer.  Various  utility  services 
including  LV  systems  namely  intercom,  data  cabling  {see 
Part  8  ‘Building  Services,  Section  6  Information  and 
Communication  Enabled  Installations’  of  the  Code), 
CCTV,  fire  alarm  shall  also  be  taken  into  account  with 
anticipated  future  requirements.  A  competent  electrical 
design  engineer  should  be  involved  at  the  planning  stage 
with  a  view  to  providing  for  an  installation  that  will  prove 
adequate  for  its  intended  purpose  and  ensure  safety, 
reliability  and  energy  efficiency  in  its  use.  The 
information/requirements  given  in  3  shall  also  be  kept 
into  consideration  while  designing  and  planning  an 
electrical  wiring  installation.  With  the  proliferation  of 
the  use  of  electrical  and  electronic  devices  in  buildings 
as  well  as  the  increase  in  the  generation/distribution 
capacities  of  power  systems,  the  hazards  of  energy  feed 
to  a  fault  or  defect  in  the  electrical  installation  have 
increased.  Reliability  of  power  supply  and  continued 
supply  even  under  abnormal  conditions  are  becoming 
very  important  not  only  for  the  operation  of  services  and 
activities  in  a  building,  but  also  for  the  life  safety  of 
occupants.  Reference  is  drawn  to  Part  0  ‘Integrated 
Approach  —  Prerequisite  for  Applying  Provisions  of  the 
Code’  of  the  Code,  which  defines  the  requirements  of 
interdisciplinary  coordination  right  from  the  sketch 
design  of  the  building.  Electricity  is  linked  to  all  services 
and  addition  of  standby  and  emergency  power  supply 
systems  adds  to  the  complexity,  thus  requiring  proper 
coordinated  design.  Generally  it  is  not  difficult  to  provide 
proper  pathways  and  equipment  installation  spaces,  if 
an  integrated  approach  is  taken  from  the  beginning.  The 
designs  should  also  have  to  keep  the  availability  of 
optimum  access  to  installations  to  ensure  proper 
maintenance.  Considering  various  utility  services  and 
to  avoid  conflict  amongst  them,  it  is  most  important  to 
estimate  space  requirement  for  electrical  work  including 
LV  systems,  at  planning  stage  and  allocate  it  in 
consultation  with  an  architect/civil  engineer. 

4.1.1  The  design  and  planning  of  an  electrical  wiring 


installation  shall  take  into  consideration  the  following: 

a)  Type  of  supply,  building  utility,  occupancy, 
envisaged  load  and  the  earthing  arrangement 
available; 

b)  Provisioning  of  air  conditioning  systems  in 
present  and/or  future  loading; 

c)  Climatic  condition,  such  as  cooling  air 
temperature,  moisture  or  such  other  conditions 
which  are  likely  to  affect  the  installation 
adversely; 

d)  Possible  presence  of  inflammable  or  explosive 
dust,  vapour  or  gas; 

e)  Degree  of  electrical  and  mechanical  protection 
necessary; 

f)  Importance  of  continuity  of  service  including 
the  possible  need  for  standby  supply; 

g)  Probability  of  need  for  modification  or  future 
extension; 

h)  Probable  operation  and  maintenance  cost 
taking  into  account  the  electricity  supply  tariffs 
available; 

j)  Relative  cost  of  various  alternative  methods; 

k)  Need  for  radio  and  telecommunication 
interference  suppression; 

m)  Ease  of  maintenance; 

n)  Safety  aspects; 

p)  Energy  conservation; 

q)  Importance  of  proper  discrimination  between 
protective  devices  for  continuity  of  supply  and 
limited  isolation  of  only  the  affected  portion; 
and 

r)  Reliability  of  power  supply  and  redundancy  (of 
sources  and  distribution  paths)  to  cater  to  the 
needs  for  emergency  power  and  standby  power 
for  continued  operation  of  systems  as  well  as 
integration  of  alternate  sources  of  energy  such 
as  diesel  generation,  solar  energy,  wind  power, 
etc. 

4.1.2  All  electrical  apparatus  shall  be  suitable  for  the 
services  these  are  intended  for. 

4.1.3  Coordination 

Proper  coordination  and  collaboration  between  the 
architect,  civil  engineer,  electrical  engineer  and 
mechanical  engineer  shall  be  effected  from  the  planning 
stage  of  the  installation.  The  electrical  engineer  shall 
be  conversant  with  the  needs  of  the  electrical  supply 
provider  for  making  electrical  supply  arrangement. 
Electrical  supplier’s  installation,  as  per  Regulations, 
needs  to  be  segregated  from  consumer’s  installation. 
Wherever  required,  prior  approval  of  drawings  shall 
be  taken  from  concerned  electrical  supplier/electrical 
inspector.  Further,  depending  on  load  and  regulation 


18 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


provisions,  consumer  will  need  to  submit  to  the 
electrical  supplier  the  details  regarding  the 
accommodation  of  substation  including  transformers, 
switch-rooms,  standby  power,  solar  photovoltaic 
panels,  lightning  scheme  for  the  approval.  Additional 
infonnation  may  be  sought  by  the  Authority  regarding 
cable  ducts,  rising  mains  and  distribution  cables,  sub¬ 
distribution  boards,  openings  and  chases  in  floors  and 
walls  for  all  required  electrical  installations,  etc. 

4.1.4  Before  starting  wiring  and  installation  of  fittings 
and  accessories,  information  should  be  exchanged 
between  the  owner  of  the  building/architect/  consultant/ 
electrical  contractor  and  the  local  supply  authority  in 
respect  of  tariffs  applicable,  types  of  apparatus  that  may 
be  connected  under  each  tariff,  requirement  of  space 
for  installing  meters,  switches,  etc,  and  for  total  load 
requirements  of  lights,  fans  and  power. 

4.1.5  While  planning  an  installation,  consideration 
should  be  taken  of  the  anticipated  increase  in  the  use  of 
electricity  for  lighting,  general  purpose  socket-outlet, 
kitchen  equipment,  air  conditioning,  utility  sockets, 
heating,  etc. 

It  is  essential  that  adequate  provision  should  be  made 
for  all  the  services  which  may  be  required  immediately 
and  during  the  intended  useful  life  of  the  building,  for 
the  householder,  who  may  otherwise  be  tempted  to  carry 
out  extension  of  the  installation  himself  or  to  rely  upon 
use  of  multi-plug  adaptors  and  long  flexible  cords,  both 
of  which  are  not  recommended. 

4.2  Substation  and  Switchrooms 

4.2.1  Location  and  Other  Requirements 

The  location  and  other  requirements  of  a  substation  and 
switchrooms  shall  be  as  given  below: 

1 )  Availability  of  power  lines  nearby  may  be  kept 
in  view  while  deciding  the  location  of  the 
substation. 

2)  The  substation  should  preferably  be  located  in 
a  separate  utility  building  and  may  be  adjacent 
to  the  generator  room,  if  any.  Location  of 
substation  in  the  basement  should  be  avoided, 
as  far  as  possible. 

3)  In  case  there  is  only  one  basement  in  a 
building,  the  substation/switchroom  shall  not 
be  provided  in  the  basement.  Also,  the  floor 
level  of  the  substation  shall  not  be  lowest  point 
of  the  basement. 

4)  Ideal  location  for  an  electrical  substation  for  a 
group  of  buildings  will  be  at  the  electrical  load 
centre.  Generally  the  load  centre  will  be 
somewhere  between  the  geometrical  centre  and 
the  air  conditioning  plant  room,  as  air 
conditioning  plant  room  will  normally  be  the 
largest  load,  if  the  building(s)  are  centrally  air 


conditioned. 

5)  In  order  to  prevent  storm  water  entering  the 
transformer  and  switch  rooms  through  the  soak- 
pits,  the  floor  level  of  the  substation/ 
switchroom  shall  be  at  least  300  mm  above  the 
highest  flood  water  level  that  may  be 
anticipated  in  the  locality.  Also,  facility  shall 
be  provided  for  automatic  removal  of  water. 

6)  Substation  shall  not  be  located  immediately 
above  or  below  plumbing  water  tanks  or  sewage 
treatment  plant  (STP)  water  tanks  at  the  same 
location. 

7)  All  door  openings  from  substation,  electrical 
rooms,  etc,  should  open  outwards.  Vertical 
shutters  (like  fire  rated  rolling  shutters)  may 
also  be  acceptable  provided  they  are  combined 
with  a  single  leaf  door  opening  outwards  for 
exit  in  case  of  emergency.  For  large  substation 
room/electrical  room  having  multiple 
equipment,  two  or  more  doors  shall  be 
provided  which  shall  be  remotely  located  from 
each  other. 

8)  If  substation  is  located  at  a  height  1  000  m 
above  MSL,  then  adequate  derating  of 
equipment  shall  be  considered. 

9)  In  case  of  HV  panel  and  transformers  located 
at  different  floors  or  at  a  distance  more  than 
20  m,  HV  isolator  shall  be  provided  at 
transformer  end. 

10)  In  case  transformer  and  main  MV/LV  panel 
room  are  located  at  different  floors  or  are  at  a 
distance  more  than  20  m,  MV/LV  isolator  shall 
be  provided  at  transformer  end.  In  case 
transfonner  and  main  MV/LV  panel  room  are 
located  at  different  floors,  the  designer  should 
also  take  care  of  the  safety  requirements  caused 
by  lack  of  direct  visibility  of  the  status  of  the 
controlling  switch.  To  cater  to  the  safety 
requirements  under  different  conditions  of 
operation  as  well  as  maintenance,  it  may  be 
necessary  to  provide  additional  isolator  or  an 
emergency  push  button  in  the  vicinity  to  trip 
the  supply.  Decision  has  to  be  taken  based  on 
the  possible  risks. 

1 1 )  No  services  or  ventilation  shafts  shall  open  into 
substation  or  switch  room  unless  specific  to 
substation  or  switch  room. 

12)  Oil-filled  installation  —  Substations  with  oil- 
filled  equipment  require  great  consideration 
for  the  fire  detection,  protection  and 
suppression.  Oil-filled  transformers  require  a 
suitable  soak  pit  with  gravity  flow  to  contain 
the  oil  in  the  event  of  the  possibility  of  oil 
spillage  from  the  transfonner  on  its  failure. 
Installation  of  oil-filled  equipment  shall  meet 
the  following  requirements: 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


19 


i)  Substations  with  oil-filled  equipment/ 
apparatus  [transformers  and  high  voltage 
panels]  shall  be  either  located  in  open  or 
in  a  utility  building.  They  shall  not  be 
located  in  any  floor  other  than  the  ground 
floor  or  the  first  basement  of  a  utility 
building.  They  shall  not  be  located  below 
first  basement  slab  of  utility  building. 
They  shall  have  direct  access  from 
outside  the  building  for  operation  and 
maintenance  of  the  equipment. 

ii)  Substations/Utility  buildings  (where  the 
substation  or  oil-filled  transformer  is 
located)  shall  be  separated  from  the 
adjoining  buildings  including  the  main 
building  by  at  least  6  m  clear  distance  to 
allow  passage  of  fire  tender  between  the 
substation/utility  building  and  adjoining 
building/main  building. 

iii)  There  shall  be  no  interconnecting 
basement  with  the  main  building 
underneath  the  oil-filled  transformers. 

iv)  Provisions  for  oil  drainage  to  a  point  at  a 
lower  level  and  separated  by  adequate  fire 
barrier  shall  be  provided.  If  there  is  a  floor 
directly  below  the  ground  floor  level  or 
first  basement  where  the  oil-filled 
transformers  and  oil-filled  circuit  breakers 
are  placed,  then  they  shall  be  separated  by 
a  fire  barrier  of  appropriate  fire  rating  as 
per  Part  4  ‘Fire  and  Life  Safety’  of  the 
Code  and  proper  oil  drainage  system  shall 
be  provided  to  avoid  possible  leakage  of 
oil  into  the  lower  floor. 

v)  Substation  equipment  having  more  than 
2  000  litre  of  oil  whether  located  indoors 
in  the  utility  building  or  outdoors  shall 
have  baffle  walls  of  4  h  fire  rating 
between  apparatus  ( see  also  Part  4  ‘Fire 
and  Life  Safety’  of  the  Code  for  fire  safety 
related  requirements). 

vi)  Provisions  shall  be  made  for  suitable  oil 
soak-pit,  and  where  use  of  more  than  9  000 
litre  of  oil  in  any  one  oil  tank,  receptacle 
or  chamber  is  involved,  provision  shall  be 
made  for  the  draining  away  or  removal  of 
any  oil  which  may  leak  or  escape  from  the 
tank,  receptacle  or  chamber  containing  the 
same.  Special  precautions  shall  be  taken 
to  prevent  the  spread  of  any  fire  resulting 
from  the  ignition  of  the  oil  from  any  cause 
and  adequate  provision  shall  be  made  for 
extinguishing  any  fire  which  may  occur. 

vii)  In  respect  of  all  oil  type  transformers 
located  at  basement,  a  kerb  (sill)  of  a 


suitable  height  shall  be  provided  at  the 
entrance  in  order  to  prevent  the  flow  of  oil 
from  a  ruptured  transformer  into  other 
parts  of  the  basement  in  the  event  of  the 
possibility  of  oil  spillage  from  the 
transformer  on  its  failure. 

viii)  Adequate  fire  barriers  or  deflectors  shall 
be  provided  to  avoid  flames  from  the 
substation  reaching  or  affecting  the  upper 
floors  ( see  also  Part  4  ‘Fire  and  Life  Safety’ 
of  the  Code). 

ix)  For  transformers  having  large  oil  content 
(more  than  2  000  litre),  Rule  44(2)  of  the 
Central  Electricity  Authority  (Measures 
Relating  to  Safety  and  Electric  Supply) 
Regulations,  20 1 0  as  amended  from  time- 
to-time  shall  apply  (see  Annex  B). 

13)  Dry-type  installation  —  In  case  electric 
substation  has  to  be  located  within  the  main 
multi-storeyed  building  itself  for  unavoidable 
reasons,  it  shall  be  a  dry-type  installation  with 
very  little  combustible  material,  such  as,  a  dry 
type  transformer  with  vacuum  (or  SF6)  breakers 
as  HT  switchgear  and  ACB  or  MCCB  as 
medium  voltage  (MV)  switchgear.  Such 
substations  shall  be  located  on  the  ground  level 
or  on  first  basement,  and  shall  have  direct 
access  from  the  outside  of  the  building  for 
operation  and  maintenance  of  the  equipment. 

Exceptionally,  in  case  of  functional  buildings, 
such  as  air  traffic  control  towers,  data  centres 
and  buildings  of  height  more  than  1 00  m  having 
high  electrical  load  requirement,  dry-type 
installations/substations  may  also  be  provided 
at  upper  level.  This  measure  will  decrease  the 
current  flow  and  short-circuit  rating  at  various 
points,  thereby  reducing  vulnerability  to  fire. 
In  such  cases,  a  base  substation  shall  be  located 
at  ground  floor/first  basement  to  cater  to  the 
main  MV/LV  panel  which  feeds  life  and  safety 
services  loads  as  defined  in  4.2.1  (29).  The  base 
substation  shall  be  located  in  such  a  way  to 
provide  direct  access  to  the  firemen  in  case  of 
any  emergency.  The  power  supply  control  to 
any  substation  or  transformer  located  at  upper 
floors  shall  be  from  the  base  substation  so  that 
in  case  of  fire,  the  electrical  supply  can  be  easily 
disconnected  to  avoid  additional  losses. 

1 4)  The  power  supply  HV  cables  voltage  shall  not 
be  more  than  12  kV  and  a  separate  dedicated 
and  fire  compartmented  shaft  should  be 
provided  for  carrying  such  high  voltage  cables 
to  upper  floors  in  a  building.  These  shall  not 
be  mixed  with  any  other  shaft  and  suitable  fire 
detection  and  suppression  measures  shall  be 
provided  throughout  the  length  of  the  cable  on 


20 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


each  floor. 

15)  The  provision  for  installation  and  removal  of 
substation  equipment  should  be  provided  from 
inside  or  outside  the  building  without  disturbing 
the  associated  major  equipment  in  the  substation. 

16)  In  case  of  compact  substation  {see  accepted 
standard  [8-2(4)]},  design  and  location  of  the 
substation  shall  ensure  safety  of  the  people 
around  the  compact  substation  installed  along 
walkways,  playgrounds,  etc.  Compact 
substation  with  incomer  voltage  of  12  kV  or 
less,  when  located  in  open  areas  shall  have 
fencing  or  barrier  (of  any  metal  based 
protection,  such  as  wire  mesh  or  chain  link, 
which  is  duly  earthed)  against  unauthorized 
contact  possibility  around  it  at  a  minimum 
distance  of  750  mm  around  it  with  access  for 
maintenance  from  all  four  sides.  For  incomer 
voltage  more  than  12  kV  and  less  than  24  kV 
the  fencing  distance  from  substation  may 
be  1  000  mm  minimum.  In  case  of  more  than 
24  kV  incomer,  the  distance  may  be  further 
increased  accordingly.  The  fencing  design 
should  take  care  of  the  servicing  and 
maintenance  requirements  of  the  substation 
equipment. 

17)  In  case  of  two  transformers  (dry  type  or 
transfonners  with  oil  quantity  less  than  2  000 
litre)  located  next  to  each  other  without 
intennittent  wall,  the  distance  between  the  two 
shall  be  minimum  1  500  mm  for  11  kV, 
minimum  2  000  mm  for  22  kV  and  minimum 
2  500  mm  for  33  kV.  Beyond  33  kV,  two 
transformers  shall  be  separated  by  baffle  wall 
of  4  h  fire  rating. 

18)  Florizontal  routing  of  HT  cable  through 
functional/occupied  areas  should  be  avoided 
in  view  of  safety. 

19)  If  dry  type  transformer  is  used,  it  may  be  located 
adjacent  to  medium  voltage  switchgear  in  the 
form  of  unit  type  substation.  In  such  a  case,  no 
separate  room  or  fire  barrier  for  the  transformer 
is  required  either  between  transformers  or 
between  transformer  and  the  switchgear, 
thereby  decreasing  the  room  space  requirement; 
however,  minimum  distances  as  specified 
in  4.2.1  (17)  shall  be  maintained  between  the 
apparatus  depending  upon  voltage  ratings. 
Layout  of  equipment  should  take  care  of  the 
need  that  any  one  piece  of  equipment  or  sub- 
assembly  can  be  taken  out  of  service  and  out 
of  the  installed  location,  while  keeping  the 
remaining  system  in  service.  Working  space  for 
access  for  maintenance  of  equipment,  while 
keeping  an  adjoining  section  of  the  substation 
live  to  maintain  power  supply  to  essential  loads, 


may  require  additional  space  between  such 
sections  of  equipment. 

20)  In  places  where  flooding  can  occur  and  water 
level  may  go  above  1  000  mm,  the  base 
substation  may  be  located  on  one  level  above 
the  ground  level  of  a  utility  building.  In  such 
cases,  one  feeder  should  feed  ground  level  and 
levels  below  with  automatic  tripping  of  the 
feeder  to  avoid  electrocution  in  case  of  live 
electricity  coming  in  contact  with  water. 
Designers  shall  use  their  discretion  in  special 
cases  and  depending  on  the  degree  of  reliability, 
redundancy  and  the  category  of  load  and  make 
suitable  provisions. 

NOTE  —  In  cases,  where  the  substation  is  located 
one  level  above  ground  level  of  utility  building,  this 
should  be  after  due  evaluation  of  the  other  risks  posed 
by  such  a  location  combined  with  the  concurrence 
for  such  a  decision  from  State  Electricity  Authority 
comprising  the  electrical  inspectorate  and  the 
distribution  licensee  and  the  fire  service. 

21)  For  acoustical  enclosures/treatment,  reference 
may  be  made  to  Part  8  ‘Building  Services’, 
Section  4  ‘Acoustics,  Sound  Insulation  and 
Noise  Control’  of  the  Code. 

22)  The  minimum  recommended  spacing  between 
the  walls  and  the  transfonner  periphery  from 
the  point  of  proper  ventilation  shall  be  in 
accordance  with  good  practice  [8-2(9)]  {see 
also  Fig.  1A).  The  actual  spacing  may  be 
different  than  those  given  in  the  figure, 
depending  on  the  circumstances,  such  as  access 
to  the  accessories.  Other  requirements  relating 
to  installation  of  transformers  shall  also  be  in 
accordance  with  good  practice  [8-2(9)]. 

23)  High  voltage  switch  room/space — The  design 
should  take  care  of  HV  equipment  space  and 
clearance  required  around  for  maintenance  and 
personnel  safety  as  given  in  5.3.6.8.  This  room 
may  preferably  have  direct  access  from  outside. 
In  case  of  substation  having  one  transformer 
and  one  source  of  supply,  the  owner  shall 
provide  one  high  voltage  switch.  In  case  of 
single  point  supply  with  two  or  more 
transformers,  the  number  of  switch  required 
will  be  one  for  incoming  supply  and  one  for 
each  transfonner.  Additional  space  may  be 
provided  keeping  in  mind  future  requirement, 
if  any.  In  case  of  duplicate  supply,  two  switches 
shall  be  provided  with  mechanical/electrical 
inter  locking  arrangement.  In  case  the  number 
of  incoming  and  outgoing  switches  exceed  five, 
bus  coupler  of  suitable  capacity  should 
invariably  be  provided. 

24)  Medium  voltage  switch  room/space — The  floor 
area  required  in  respect  of  medium  voltage 
switchgear  room  may  be  detennined  keeping  in 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


21 


view  the  number  and  type  of  incoming/outgoing 
bus  coupler  switches  including  likely  expansion 
in  future  and  space  requirement  as  given  in 
5.3.6.8.  The  additional  requirements  of  MV 
switchroom  when  located  separate  from  the 
substation  shall  be  as  per  4.2.4. 

25)  Other  requirements  relating  to  installation  of 
switchgears  and  controlgears  as  given  in  good 
practice  [8-2(10)]  shall  also  be  complied  with. 

26)  The  minimum  height  of  substation  room/HV 
switch  room/MV  switch  room  shall  be  arrived 
at  considering  1  200  mm  clearance 
requirement  from  top  of  the  equipment  to  the 
below  of  the  soffit  of  the  beam  ( see  also 
Annex  C).  In  case  cable  entry/exit  is  from 
above  the  equipment  (transformer,  HV 
switchgear,  MV  switchgear),  height  of 
substation  room/HV  switch  room/MV  switch 
room  shall  also  take  into  account  requirement 
of  space  for  turning  radius  of  cable  above  the 
equipment  height. 

27)  All  the  rooms  shall  be  provided  with  partitions 
up  to  the  ceiling  and  shall  have  proper 
ventilation.  Special  care  should  be  taken  to 
dissipate  transformer  heat  and  where 
necessary  fresh  air  louvers  at  lower  level  and 
exhaust  fans  at  higher  level  shall  be  provided 
at  suitable  locations. 

28)  In  case  of  cable  trench  in  substation/HV  switch 
room/MV  switch  room,  the  same  shall  be 
adequately  drained  to  ensure  no  water  is 
stagnated  at  any  time  with  live  cables. 

29)  Power  supply  to  emergency  fire  and  life  safety 
systems  —  Emergency  power  supplying 
distribution  system  for  critical  requirement  for 
functioning  of  fire  and  life  safety  system  and 
equipment,  shall  be  planned  for  efficient  and 
reliable  power  and  control  supply  to  the 
following  systems  and  equipment  where 
provided: 

i)  Fire  pumps; 

ii)  Pressurization  and  smoke  venting; 
including  its  ancillary  systems  such  as 
dampers  and  actuators; 

iii)  Fireman’s  lifts  (including  all  lifts). 

iv)  Exit  signage  lighting; 

v)  Emergency  lighting; 

vi)  Fire  alarm  system; 

vii)  Public  address  (PA)  system  (relating  to 
emergency  voice  evacuation  and 
annunciation); 

viii)  Magnetic  door  hold  open  devices;  and 

ix)  Lighting  in  fire  command  centre  and 
security  room. 


Power  supply  to  these  systems  and  equipment 
shall  be  from  normal  and  emergency  (standby 
generator)  power  sources  with  change  over 
facility.  It  shall  be  ensured  that  in  case  the  power 
supply  is  from  HT  source/HT  generation, 
transformers  should  be  planned  in  stand-by 
capacity  to  ensure  continuity  of  power  to  such 
systems.  Wherever  transformers  are  installed 
at  higher  levels  in  buildings  and  backup  DG 
sets  are  of  higher  voltage  rating,  then  dual 
redundant  cables  shall  be  taken  to  all 
transformers.  The  generator  shall  be  capable 
of  taking  starting  current  of  all  the  fire  and  life 
safety  systems  and  equipment  as  above.  Where 
parallel  HV/LV  supply  from  a  separate 
substation  fed  from  different  grid  is  provided 
with  appropriate  transformer  for  emergency,  the 
provision  of  generator  may  be  waived  in 
consultation  with  the  Authority. 

The  power  supply  to  the  panel/distribution 
board  of  these  fire  and  life  safety  systems  shall 
be  through  fire  proof  enclosures  or  circuit 
integrity  cables  or  through  alternate  route  in 
the  adjoining  fire  compartment  to  ensure  that 
supply  of  power  is  reliable  to  these  systems  and 
equipment.  It  is  to  be  ensured  that  the  cabling 
from  the  adjoining  fire  compartment  is  to  be 
protected  within  the  compartment  of 
vulnerability.  The  location  of  the  panel/ 
distribution  board  feeding  the  fire  and  life  safety 
system  shall  be  in  fire  safe  zone  ensuring  supply 
of  power  to  these  systems. 

Cables  for  fire  alann  and  PA  system  shall  be 
laid  in  metal  conduits  or  armoured  to  provide 
physical  segregation  from  the  power  cables. 

30)  Other  requirements  as  given  in  Central 
Electricity  Authority  (Measures  relating  to 
Safety  and  Electricity  Supply)  Regulations, 
2010  as  amended  shall  also  be  complied  with. 
The  fire  safety  requirements  for  substation  and 
electrical  rooms,  including  fire  rating 
requirements  of  substations  enclosure,  that  is, 
walls,  floor,  ceiling,  openings,  doors,  etc,  as 
given  in  Part  4  ‘Fire  and  Life  Safety’  of  the 
Code  shall  also  be  complied  with. 

4.2.2  Layout  of  Substation 

4.2.2. 1  In  allocating  the  area  of  substation,  it  is  to  be 
noted  that  the  flow  of  electric  power  is  from  supply 
company’s  meter  room  to  HV  room,  then  to  transformer 
and  finally  to  the  MV  switchgear  room.  The  layout  of 
the  room  and  trenches  of  required  depth  shall  be  in 
accordance  with  this  flow,  so  as  to  optimize  the  cables, 
bus-trunking,  etc.  Visibility  of  equipment  controlled  from 
the  operating  point  of  the  controlling  switchgear  is  also 
a  desirable  feature,  though  it  may  not  be  achievable  in 
case  of  large  substations.  Substations  shall  not  be  located 


22 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


at  or  across  expansion  joints.  The  rooms/spaces  required 
in  a  substation  shall  be  provided  as  given  below: 

a)  Supply  company  s  meter  room ,  generally  at  the 
periphery  of  the  premise  with  direct  access  from 
the  road/outside; 

b)  HV  isolation  room ,  required  in  case  the 
substation  is  away  from  the  meter  room  and  is 
planned  adjacent  to  meter  room  for 
disconnecting  supply  in  case  of  any  repair 
required  between  meter  room  and  substation; 

c)  HV  panel  room/space,  located  adjacent  to 
transformer; 

d)  Transformer  room/space,  separate  space  in  case 
of  oil-filled  transformer  and  combined  space 
in  case  of  dry  type  transformer; 

e)  MV  isolation  room/space,  required  in  case  MV 


panel  is  away  from  transformer  or  on  a  different 
level  for  isolating  supply  in  case  of  any  repair 
required  between  transformer  and  MV 
switchgear;  and 

f)  Main  MV  panel  room/space,  required  for 
distribution  to  different  facility/utility  in  a 
building. 

A  typical  layout  of  a  substation  is  shown  in  Fig.  IB. 

4.2.2.2  Capacity  and  size  of  substation 

The  capacity  of  a  substation  depends  upon  the  area  of 
the  building  and  its  type.  The  capacity  of  substation  may 
be  determined  based  on  the  load  requirements  ( see 
also  3.3).  Ratings  of  electrical  equipment  as  given  in 
6.1,  may  be  assumed,  unless  the  values  are  known  or 
specified  and  diversity  requirements  as  given  below  may 
be  used  for  load  assessment: 


SI 

Purpose  of  Final  Circuit  Fed 

Typical  Allowances  for  Diversity  Based  on: 

No. 

from  Conductors  or 

Type  of  Building 

Switchgear  to  which 

- 

Diversity  Applies 

Individual  House  Hold 

Small  Shops, 

Small  Hotels, 

Installations,  Including 

Stores,  Offices  and 

Boarding  Houses, 

Individual  Dwelling 

Business 

etc 

of  a  Block 

Premises 

(1) 

(2) 

(3) 

(4) 

(5) 

i) 

Lighting 

66  percent  of  total  current 

90  percent  of  total 

75  percent  of  total 

demand 

current  demand 

current  demand 

ii) 

Heating  and  power  [see  also 

100  percent  of  total 

100  percent  of  full 

1 00  percent  of  full 

SI  No.  (iii)  to  (iv)] 

current  demand  up  to 

load  of  largest 

load  of  largest 

10  A 

appliance 

appliance 

+  50  percent  of  any 

+  75  percent  of 

+  80  percent  of 

current  demand  in  excess 

remaining 

second  largest 

of  10  A 

appliances 

appliance  + 

60  percent  of 

remaining 

appliances 

hi) 

Cooking  appliances 

10  A  + 

100  percent  of  full 

1 00  percent  of  full 

30  percent  frill  load  of 

load  of  largest 

load  of  largest 

connected  cooking 

appliance 

appliance 

appliances  in  excess  of 

+  80  percent  of 

+  80  percent  of 

10  A 

full  load  of  second 

full  load  of  second 

+  6  A  if  socket-outlet 

largest  appliance 

largest  appliance 

incorporated  in  the  unit 

+  60  percent  of 

+  60  percent  of 

full  load  of 

full  load  of 

remaining 

remaining 

appliances 

appliances 

iv) 

Motors  (other  than  lift 

100  percent  of  full 

1 00  percent  of  full 

motors  which  are  subject  to 

load  of  largest 

load  of  largest 

special  consideration) 

motor 

motor 

+  80  percent  of 

+  50  percent  of 

full  load  of  second 

full  load  of 

largest  motor 

remaining  motors 

PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


23 


SI 

No. 

Purpose  of  Final  Circuit  Fed 
from  Conductors  or 
Switchgear  to  which  Diversity 
Applies 

(2) 

Typical  Allowances  for  Diversity  Based  on: 

Type  of  Building 

(1) 

Individual  House  Hold 
Installations,  Including 
Individual  Dwelling 
of  a  Block 

(3) 

Small  Shops, 
Stores,  Offices 
and  Business 
Premises 

(4) 

Small  Hotels, 
Boarding  Houses, 
etc 

(5) 

+  60  percent  of 
full  load  of 
remaining  motors 

v) 

Water  heater  [instantaneous 
type1’] 

100  percent  of  full 
load  of  largest 
appliance 

+  100  percent  of  full 
load  of  second  largest 
appliance 

+  25  percent  of  frill 
load  of  remaining 
appliances 

100  percent  of 
full  load  of 
largest  appliance 
+  100  percent  of 
full  load  of 
second  largest 
appliance 
+  25  percent  of 
full  load  of 
remaining 
appliances 

1 00  percent  of  full 
load  of  largest 
appliance 

+  100  percent  of  full 
load  of  second  largest 
appliance 

+  25  percent  of  full 
load  of  remaining 
appliances 

vi) 

Water  heater  (thermostatically 
controlled) 

No  diversity 
allowable21 

vii) 

Floor  warming  installations 

No  diversity 
allowable2’ 

viii) 

Water  heaters  thermal  storage 
space  heating  installations 

No  diversity 
allowable2’ 

ix) 

Standard  arrangements  of  final 
circuits  in  accordance  with 
good  practice  [8-2(11)] 

100  percent  of  the 
current  demand  of  the 
largest  circuit 
+  40  percent  of  the 
current  demand  of 
every  other  circuit 

100  percent  of 
the  current 
demand  of  the 
largest  circuit 
+  50  percent  of 
the  current 

demand  of  every 
other  circuit 


x) 


Socket  outlets  other  than  those 
included  in  SI  No.  (ix)  and 
stationary  equipment  other 
than  those  listed  above 


100  percent  of  the 
current  demand  of  the 
largest  point 
+  40  percent  of  the 
current  demand  of 
every  other  point 


100  percent  of 
the  current 
demand  of  the 
largest  point 
+  75  percent  of 
the  current 
demand  of  every 
other  point 


100  percent  of  the 
current  demand  of  the 
largest  point 
+  75  percent  of  the 
current  demand  of 
every  point  in  main 
rooms  (dining  rooms, 
etc) 

+  40  percent  of  the 
current  demand  of 
every  other  point 


NOTE  —  Diversity  may  be  considered ,  if  multiple  units  of  water  he  ater  are  there  in  an  individual  house  -hold  installation,  including 
individual  dwelling  of  a  block 

!)  For  the  purpose  of  the  table,  an  instantaneous  water  heater  is  deemed  to  be  a  water  heater  of  any  loading  which  heats  water  only 
while  the  tap  is  turned  o  n  and  therefore  uses  electricity  intermittently. 

2)  It  is  important  to  ensure  that  the  distribution  boards  are  of  sufficient  rating  to  take  the  total  load  connected  to  them  without  the 
application  of  any  diversity. 


24 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


After  calculating  the  electrical  load  on  the  above  basis, 
an  overall  load  factor  of  70  to  90  percent  is  to  be  applied 
to  arrive  at  the  minimum  capacity  of  substation.  A  future 
load  may  also  be  considered  for  substation  sizing 
( see  3.3).  The  area  required  for  substation  and 
transformer  room  for  different  capacities  is  given  in 
Annex  C  for  general  guidance.  For  reliability,  it  is 
recommended  to  split  the  load  into  more  than  one 
transformer  and  also  provide  for  standby  transformer 
as  well  as  multiple  sources,  bus-section,  etc. 

4.3  Emergency  Power  Backup  System 

4.3.1  Location 

The  emergency  power  supply  (such  as  generating  sets) 
should  not  be  allowed  to  be  installed  above  ground  floor 
or  below  the  first  basement  level  of  the  building.  In 
case  of  DG  set  located  in  basement,  the  ceiling  of  the 
DG  room  shall  be  the  ground  floor  slab.  It  is  preferable 


to  install  the  standby  generator  in  utility  building.  If 
installed  in  the  enclosed  space,  facilities  for  forced 
ventilation  shall  be  provided  such  that  there  is  minimum 
derating  of  the  equipment.  The  generating  set  should 
preferably  be  housed  adjacent  to  MV  switchgear  in  the 
substation  building  to  enable  transfer  of  electrical  load 
efficiently  and  also  to  avoid  transfer  of  vibration  and 
noise  to  the  main  building. 

4.3.2  Room  for  Emergency  Power  Backup  System 

The  capacity  of  standby  generating  set  shall  be  sized 
for  emergency  fire  and  life  safty  systems  [see  4.2.1  (29)] 
and  other  utilities  as  required  and  identified  for 
functional  requirement  of  the  building.  Having  chosen 
the  capacity  and  number  of  generating  sets,  required 
space  may  be  provided  for  their  installation  (see  Annex 
D  for  general  guidance).  There  shall  be  provision  of 
separate  direct  escape  and  entry  from  outside  so  that  in 
case  of  fire,  electrical  supplies  can  be  disconnected  to 


TRANSFORMER  WITH  WALL  ON  TWO  SIDES 


TRANSFORMER  WITH  WALL  ON  THREE  SIDES 


TRANSFORMER  IN  ENCLOSED  ROOM 


X  TO  BE  AS  PER  4.2.1(17) 
MULTIPLE  TRANSFORMERS  IN  A  ROOM 


1A  MINIMUM  RECOMMNEDED  SPACING  BETWEEN  THE  TRANSFORMER  PERIPHERY  AND  WALLS 

Fig.  1  —  ( Continued ) 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


25 


3000  Max 


PANEL  ROOM 


HT  PANEL 


ID 

DRY  TYPE 

o 

6 

CO 

(9 

(9 

TRANSFORMER  -  n 

6 

6 

6 

6 

d 

*3  Os 

DG  ROOM 


r-X—} 

pX— 

pXp 

DRY TYPE 
TRANSFORMER- 1 

HV]  [LV 

DRY TYPE 
TRANSFORMER -2 

HV]  [LV 

DRY  TYPE 

TRANSFORMER  -  3 

HV]  [Tv 

DRY TYPE 
TRANSFORMER- n 

|Iv 

FRONT 


CAPACITOR  CAPACITOR  CAPACITOR  CAPACITOR 

PANEL -1  PANEL -2  PANEL -3  PANEL -4 

CAPACITOR 

PANEL -n 

MAIN  MV  PANEL 

¥  T 

FRONT 

4 4 4 4 

MAIN  MV  PANEL 

BACK 


SPACE  FOR  EQUIPMENT  ENTRY/  EXIT 


<t> 


X  TO  BE  AS  PER  4.2.1(17) 


All  dimensions  in  millimetres. 


IB  TYPICAL  LAYOUT  OF  SUBSTATION  WITH  DRY  TYPE  EQUIPMENT  IN  A  SINGLE  ROOM 

Fig.  1  Typical  Layout  of  Substation  Including  Minimum  Recommended  Spacing  of 
Transformer  Periphery  from  Walls 


26 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


avoid  additional  losses  which  may  be  caused  due  to 
electrical  supply,  present  at  the  time  of  fire.  The  height 
of  diesel  generating  (DG)  set  rooms  shall  however  be 
not  more  than  3  000  mm  above  the  DG  set  height,  unless 
required  due  to  DG  room  ventilation  requirements. 
Adequate  space  shall  be  provided  for  storing  of  fuel. 
Facilities  including  space  at  appropriate  positions, 
relative  to  the  location  of  the  installed  equipment  has 
to  be  kept  in  the  layout  design  for  removal  of  equipment 
or  sub-assemblies  for  repair  or  maintenance.  When  it 
is  located  at  a  place,  other  than  the  ground  level  with 
direct  equipment  access,  a  hatch  or  ramp  shall  be 
provided. 

4.3.3  Installation  and  Other  Requirements 

Following  installation  and  other  requirements  shall  also 
be  complied  with: 

a)  Day-oil  tanks  for  the  DG  sets  shall  be  in 
compliance  with  The  Petroleum  Act,  1934. 

b)  The  emergency  installation  shall  comply  with 
the  norms  laid  down  by  the  Central  Pollution 
Control  Board  (CPCB)  and  shall  also  be  in 
compliance  with  The  Petroleum  Act,  1 934  and 
guidelines  of  Oil  Industry  Safety  Directorate 
(OISD).  Compartmentation  for  fire  protection 
with  detection  and  first-aid  protection 
measures  is  essential. 

NOTE  —  Different  type  of  fire  safety  requirements 
exists  for  the  diesel  engine  and  generator  for  the  oil 
storage  area  and  for  the  switchgear  {see  also  Part  4 
‘Fire  and  Life  Safety  ‘of  the  Code). 

c)  Acoustic  enclosure  for  DG  sets/acoustic  lining 
of  the  DG  room  and  ventilation  system  for  DG 
room  shall  be  in  line  with  the  requirements  of 
CPCB.  If  DG  set  is  located  outdoors,  it  shall 
be  housed  in  acoustics  enclosure  as  per  the 
requirements  of  CPCB  norms.  For  acoustical 
enclosures/treatment,  reference  shall  also  be 
made  to  Part  8  ‘Building  Services,  Section  4 
Acoustics,  Sound  Insulation  and  Noise 
Control’  of  the  Code. 

d)  The  generator  house  should  have  proper 
ventilation  for  engine  combustion 
requirements  and  as  well  as  for  the  body  heat 
removal  apart  from  the  heat  removal  from 
radiator  or  cooling  tower,  fire  fighting 
equipment,  etc.  The  other  requirements  given 
in  Part  4  ‘Fire  and  Life  Safety’  of  the  Code 
for  room  for  emergency  power  backup  system 
including  DG  set  room  shall  also  be  complied 
with. 

e)  Other  environmental  requirements  under  the 
provisions  of  Environment  Protection  Rules, 
1986  and  norms  laid  down  by  CPCB,  as 
amended  from  time-to-time  shall  be  taken  into 


account  particularly  from  the  aspect  of  engine 
emissions  including  the  height  of  exhaust  pipe 
and  permitted  noise  levels/controls. 

4.4  Location  of  MV/LV  Switch  Room  Other  than  in 
Substation 

In  large  installations  other  than  where  a  substation  is 
provided,  a  separate  switch  room  shall  be  provided; 
this  shall  be  located  as  close  to  the  electrical  load  centre 
as  possible,  on  the  ground  floor  or  on  the  first  basement 
level  of  the  building.  Suitable  cable  trays  shall  be  laid 
with  minimum  number  of  bends  from  the  points  of  entry 
of  the  main  supply  cable  to  the  position  of  the  main 
switchgear.  The  switch  room  shall  also  be  placed  in 
such  a  position  that  riser  shafts  may  readily  be  provided 
therefrom  to  the  upper  floors  of  the  building  in  one 
straight  vertical  run.  In  larger  buildings,  more  than  one 
riser  shaft  may  be  required  and  then  horizontal  trays 
may  also  be  required  for  running  cables  from  the  switch 
room  to  the  foot  of  each  rising  main.  Such  cable  trays 
shall  either  be  reserved  for  specific  voltage  grades  or 
provided  with  a  means  of  segregation  for  medium,  low 
and  extra  low  voltage  installations,  such  as  call-bell 
systems,  telephone  installations,  fire  detection  and 
alarm  system,  security  systems,  data  cables  and 
announcement  or  public  address  system.  Cables/wires 
for  emergency  fire  and  life  safety  services  and  their 
routing  shall  be  in  accordance  with  4.2.1  (29)  and  Part 
4  ‘Fire  and  Life  Safety’  of  the  Code  so  that  these 
services  are  maintained  even  in  the  event  of  a  fire. 

4.5  Location  and  Requirements  of  Distribution 
Panels 

All  distribution  panels,  switchgears  shall  be  installed 
in  readily  accessible  position.  The  electrical  control 
gear  distribution  panels  and  other  apparatus,  which  are 
required  on  each  floor  may  conveniently  be  mounted 
adjacent  to  the  rising  mains,  and  adequate  space 
considering  clearances  required  as  per  5.3. 6.8  shall  be 
provided  at  each  floor  for  this  purpose. 

4.6  Substation  Safety 

The  owner  and  the  operator  of  any  substation  shall  be 
collectively  and  severally  be  responsible  for  any  lapse 
or  neglect  leading  to  an  accident  or  an  incidence  of  an 
avoidable  abnormality  and  shall  take  care  of  the 
following  safety  requirements: 

a)  Enclose  the  substation  or  similar  equipment 
where  necessary  to  prevent,  so  far  as  is 
reasonably  practicable,  danger  of  electric 
shock  or  unauthorized  access; 

b)  Enclose  any  part  of  the  substation  which  is 
open  to  the  air,  with  a  fence  (earthed  efficiently 
at  both  ends)  or  wall  not  less  than  1  800  mm 
(preferably  not  less  than  2  400  mm)  in  height; 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


27 


to  prevent,  so  far  as  is  reasonably  practicable, 
danger  of  electric  shock  or  unauthorized 
access; 

c)  Ensure  that  there  are  at  all  times  displayed, 

1)  sufficient  safety  signs  of  such  size  and 
placed  in  such  positions  as  are  necessary 
to  give  due  warning  of  such  danger  as  is 
reasonably  foreseeable  in  the 
circumstances; 

2)  a  notice  which  is  placed  in  a  conspicuous 
position  and  which  gives  the  location  or 
identification  of  the  substation,  the  name 
of  each  generator  or  distributor  who  owns 
or  operates  the  substation  equipment 
making  up  the  substation  and  the 
telephone  number  where  a  suitably 
qualified  person  appointed  for  this 
purpose  by  the  generator  or  distributor 
will  be  in  constant  attendance;  and 

3)  such  other  signs,  which  are  of  such  size 
and  placed  in  such  positions,  as  are 
necessary  to  give  due  warning  of  danger 
having  regard  to  the  siting  of,  the  nature 
of,  and  the  measures  taken  to  ensure  the 
physical  security  of,  the  substation 
equipment; 

d)  Take  all  reasonable  precautions  to  minimize 
the  risk  of  fire  associated  with  the  equipment; 
and 

e)  Ensure  that,  in  addition  to  provisions 
mentioned  in  (c),  name  and  emergency 
telephone  number  of  the  authorized  personnel 
shall  also  be  displayed  at  the  substation  and 
instructions  covering  schematic  diagram; 
requirements  of  switchgear  interlocking,  if 
any;  and  permission  requirements,  if  any,  for 
load  limitations  on  (incoming)  feeders;  be  also 
prominently  displayed. 

4.7  Overhead  Lines,  Wires  and  Cables 

All  erections/alterations  having  relation  to  overhead 
lines,  wires  and  cables  shall  comply  with  Central 
Electricity  Authority  regulations  and  the  following. 
However,  in  case  of  any  conflict,  the  regulations  shall 
prevail. 

4.7.1  Height  Requirement 

4.7.1. 1  While  overhead  lines  may  not  be  relevant  within 
buildings,  regulations  related  to  overhead  lines  are  of 
concern  from  different  angles  as  follows: 

a)  Overhead  lines  may  be  required  in  building 
complexes,  though  use  of  underground  cables 
is  the  preferred  alternative. 

b)  Overhead  lines  may  be  passing  through  the 


site  of  a  building.  In  such  a  case  the  safety 
aspects  are  important  for  the  construction 
activity  in  the  vicinity  of  the  overhead  line  as 
well  as  portions  of  low  height  buildings  that 
may  have  to  be  constructed  below  the 
overhead  lines.  Overhead  lines  running 
adjacent  to  buildings  pose  hazard  from  the 
aspect  of  certain  maintenance  activity  (such 
as  use  of  a  ladder  on  external  face  of  a 
building)  causing  temporary  compromise  of 
the  minimum  safety  clearance. 

4.7. 1.2  If  at  any  time  subsequent  to  the  erection  of  an 
overhead  line,  whether  covered  with  insulating  material 
or  not,  or  underground  cable,  any  person  who  proposes 
to  erect  a  new  building  or  structure  or  to  raise  any  road 
level  or  to  carry  out  any  other  type  of  work  whether 
permanent  or  temporary  or  to  make  in  or  upon  any 
building,  or  structure  or  road,  any  permanent  or 
temporary  addition  or  alteration,  in  proximity  to  an 
overhead  line  or  underground  cable,  such  person  and 
the  contractor  whom  he  employs  to  carry  out  the 
erection,  addition  or  alteration,  shall  give  intimation  in 
writing  of  his  intention  to  do  so,  to  the  supplier  or  owner 
and  to  the  Electrical  Inspector  and  shall  furnish 
therewith  a  scale  drawing  showing  the  proposed 
building,  structure,  road  or  any  addition  or  alteration 
and  scaffolding  thereof  required  during  the 
construction.  In  this  connection,  Regulation  63  of 
Central  Electricity  Authority  (Measures  Relating  to 
Safety  and  Electricity  Supply)  Regulations,  2010,  as 
amended  from  time-to-time  shall  also  be  complied  with 
( see  Annex  B). 

4.7.1.3  Any  person  responsible  for  erecting  an  overhead 
line  will  keep  informed  the  authority(s)  responsible  for 
services  in  that  area  for  telecommunication,  gas 
distribution,  water  and  sewage  network,  roads  so  as  to 
have  proper  coordination  to  ensure  safety.  He  shall  also 
publish  the  testing,  energizing  programme  for  the  line 
in  the  interest  of  safety. 

4.7.1.4  For  minimum  distance  (vertical  and  horizontal) 
of  electric  lines/wires/cables  from  buildings,  reference 
may  be  made  to  Part  3  ‘Development  Control  Rules 
and  General  Building  Requirements’  of  the  Code.  In 
this  connection.  Regulations  58,  60,  61,  and  65  of 
Central  Electricity  Authority  (Measures  Relating  to 
Safety  and  Electricity  Supply)  Regulations,  2010,  as 
amended  from  time-to-time  shall  also  be  complied  with 
( see  Annex  B). 

4.7. 1.5  Regulation  64  of  Central  Electricity’  Authority 
(Measures  Relating  to  Safety  and  Electricity  Supply) 
Regulations,  2010,  as  amended  from  time-to-time, 
which  govern  conditions  related  to  the  storage  of 
material  including  storage  of  construction  material  at 
a  construction  site,  or  other  materials  in  a  building  in 


28 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


vicinity  of  overhead  lines  and  underground  cables,  shall 
also  be  complied  with  ( see  Annex  B). 

4.7.2  Position,  Insulation  and  Protection  of  Overhead 
Lines 

4. 7.2.1  Any  part  of  an  overhead  line  which  is  not 
connected  with  earth  and  which  is  not  ordinarily 
accessible  shall  be  supported  on  insulators  or 
surrounded  by  insulation.  Any  part  of  an  overhead  line 
which  is  not  connected  with  earth  and  which  is 
ordinarily  accessible  shall  be, 

a)  made  dead;  or 

b)  so  insulated  that  it  is  protected,  so  far  it  is 
reasonably  practicable,  against  mechanical 
damage  or  interference;  or 

c)  adequately  protected  to  prevent  danger. 

4.7.2.2  Any  person  responsible  for  erecting  a  building 
or  structure  which  will  cause  any  part  of  an  overhead 
line  which  is  not  connected  with  earth  to  become 
ordinarily  accessible  shall  give  reasonable  notice  to  the 
licensee  or  distributor  who  owns  or  operates  the 
overhead  line  of  his  intention  to  erect  that  building  or 
structure. 

The  expression  ‘ordinarily  accessible’  means  the 
overhead  line  might  be  reachable  by  hand  if  any 
scaffolding,  ladder  or  other  construction  was  erected 
or  placed  on/in,  against  or  near  to  a  building  or 
structure. 

4.7.2.3  Any  bare  conductor  not  connected  with  earth, 
which  is  part  of  a  low  voltage  overhead  line,  shall  be 
situated  throughout  its  length  directly  above  a  bare 
conductor  which  is  connected  with  earth. 

4.7.3  Precautions  against  Access  and  Warnings  of 
Dangers 

4. 7.3.1  Every  support  carrying  a  high  voltage  overhead 
line  shall  be  fitted  with  anti-climbing  devices  to  prevent 
any  unauthorized  person  from  reaching  a  position  at 
which  any  such  line  will  be  a  source  of  danger.  In  this 
connection,  Regulation  73(3)  of  Central  Electricity 
Authority  (Measures  Relating  to  Safety  and  Electricity 
Supply)  Regulations,  2010,  as  amended  from  time-to- 
time  shall  also  be  complied  with  ( see  Annex  B). 

4. 7.3.2  Every  support  carrying  a  high  voltage  overhead 
line,  and  every  support  carrying  a  low  voltage  overhead 
line  incorporating  bare  phase  conductors,  shall  have 
attached  to  it  sufficient  safety  signs  and  placed  in  such 
positions  as  are  necessary  to  give  due  warning  of  such 
danger  as  is  reasonably  foreseeable  in  the 
circumstances. 

4. 7.3.3  Poles  supporting  overhead  lines  near  the  road 
junctions  and  turnings  shall  be  protected  by  a  masonry 


or  earth  fill  structure  or  metal  barricade,  to  prevent  a 
vehicle  from  directly  hitting  the  pole,  so  that  the  vehicle, 
if  out  of  control,  is  restrained  from  causing  total  damage 
to  the  live  conductor  system,  likely  to  lead  to  a 
hazardous  condition  on  the  road  or  footpath  or  building. 

4.7.4  Fitting  of  Insulators  to  Stay  Wires 

Every  stay  wire  which  forms  part  of,  or  is  attached  to, 
any  support  carrying  an  overhead  line  incorporating 
bare  phase  conductors  (except  where  the  support  is  a 
lattice  steel  structure  or  other  structure  entirely  of  metal 
and  connected  to  earth)  shall  be  fitted  with  an  insulator, 
no  part  of  which  shall  be  less  than  3  m  above  ground  or 
above  the  normal  height  of  any  such  line  attached  to 
that  support. 

4.8  Maps  of  Underground  Networks 

4.8.1  Any  person  or  organization  or  authority  laying 
cables  shall  contact  the  local  authority  in  charge  of  that 
area  and  find  out  the  layout  of, 

a)  water  distribution  pipe  lines  in  the  area; 

b)  sewage  distribution  network; 

c)  telecommunication  network, 

d)  gas  pipeline  network;  and 

e)  existing  power  cable  network, 

and  plan  the  cable  network  in  such  a  manner  that  the 
system  is  compatible,  safe  and  non-interfering  either 
during  its  installation  or  during  its  operation  and 
maintenance.  Plan  of  the  proposed  cable  installation 
shall  be  brought  to  the  notice  of  the  other  authorities 
referred  above. 

4.8.2  Suitable  cable  markers  and  danger  sign  as  will 
be  appropriate  for  the  safety  of  the  workmen  of  any  of 
the  systems  shall  be  installed  along  with  the  cable 
installation.  Cable  route  markers  shall  be  provided  at 
every  20  m  and  also  at  turnings  and/or  crossings. 

4.8.3  Notification  of  testing  and  energization  of  the 
system  shall  also  be  suitably  publicized  for  ensuring 
safety. 

4.8.4  Any  person  or  organization  or  authority  associated 
with  the  operation  and  maintenance  of  services  in  a 
complex  is  required  to  have  a  complete  integrated 
diagram  or  drawings  of  all  services  with  particular 
emphasis  on  the  hidden  pipes,  cables,  etc,  duly  kept 
up-to-date  by  frequent  interaction  with  all  agencies 
associated  with  the  maintenance  work. 

Organization  or  agency  responsible  for  laying  cables 
shall  have  and,  so  far  it  is  reasonably  practicable,  keep 
up-to-date,  a  map  or  series  of  maps  indicating  the 
position  and  depth  below  surface  level  of  all  networks 
or  parts  thereof  which  he  owns  or  operates.  Where 
adequate  mapping  has  not  been  done  and  the  excavation 


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29 


for  cable  laying  reveals  lines  pertaining  to  any  of  the 
other  services,  record  of  three  dimensional  location 
should  be  marked  and  recorded.  Even  where  mapping 
exists,  it  may  be  examined  if  the  records  have  become 
obsolete  due  to  change  such  as,  in  road  level.  Any  map 
prepared  or  kept  shall  be  available  for  inspection  by 
any  authority,  such  as  municipality,  water  supply, 
sewage,  service  providers,  general  public  provided  they 
have  a  reasonable  cause  for  requiring  reference  to  any 
part  of  the  map. 

4.8.5  Any  agency  working  on  any  one  or  more  service 
(occupying  the  underground  space  for  service  pipes, 
cables,  etc)  should  keep  the  other  agencies  informed 
of  the  work  so  that  an  inadvertent  action  will  not  cause 
a  disruption  of  service.  Each  agency  should  be 
responsible  for  keeping  the  latest  information  with  the 
central  authority  of  such  records  and  should  be 
responsible  to  ensure  that  the  modifications,  if  any  are 
duly  updated  and  notified  among  the  other  agencies. 

5  DISTRIBUTION  OF  SUPPLY  AND  CABLING 

5.1  General 

5.1.1  In  the  planning  and  design  of  an  electrical  wiring 
installation,  due  consideration  shall  be  made  of  all  the 
prevailing  conditions.  It  is  recommended  that  advice 
of  a  competent  electrical  engineer  be  sought  at  the  initial 
stage  itself  with  a  view  to  providing  an  installation  that 
will  prove  adequate  for  its  intended  purpose,  be  reliable, 
safe  and  efficient. 

5.1.2  A  certain  redundancy  in  the  electrical  system  is 
necessary  and  has  to  be  built  in  from  the  initial  design 
stage  itself.  The  extent  of  redundancy  will  depend  on 
the  type  of  load,  its  criticality,  normal  hours  of  use, 
quality  of  power  supply  in  that  area,  coordination  with 
the  standby  power  supply,  capacity  to  meet  the  starting 
current  requirements  of  large  motors,  etc. 

5.1.3  In  modern  building  technology,  following  high 
demands  are  made  of  the  power  distribution  system 
and  its  individual  components: 

a)  Long  life  and  good  service  quality; 

b)  Safe  protection  in  the  event  of  fire; 

c)  Low  fire  load; 

d)  Flexibility  in  load  location  and  connection,  but 
critical  in  design; 

e)  Low  space  requirement;  and 

f)  Minimum  effort  involved  in  carrying  out 
retrofits. 

5.1.4  The  high  load  density  in  modern  large  buildings 
and  high  rise  buildings  demands  compact  and  safe 
solution  for  the  supply  of  power.  The  use  of  busbar 
trunking  system  is  ideal  for  such  applications.  Busbar 
trunking  can  be  installed  in  vertical  risers  shafts  or 


horizontally  in  passages  for  transmission  and 
distribution  of  power.  They  allow  electrical  installations 
to  be  planned  in  a  simple  and  neat  manner.  In  the 
building  complexes,  additional  safety  demands  with 
respect  to  fire  barriers  and  fire  load  can  also  be  met 
with  the  use  of  busbar  trunking.  Busbar  trunking  system 
also  reduces  the  combustible  material  near  the  area  with 
high  energy  in  comparison  with  other  distribution 
systems  such  as  cables  and  makes  the  building  safe  from 
the  aspect  of  vulnerability  to  fire  of  electrical  origin. 
In  addition,  unlike  cable  systems  the  reliability  of  a 
busbar  trunking  system  is  very  high.  These  systems  also 
require  very  little  periodic  maintenance.  Choice  of 
busbar  trunking  for  distribution  in  buildings  can  be 
made  on  the  basis  of, 

a)  reduced  fire  load  (drastically  reduced  in 
comparison  to  the  cable  system); 

NOTE  —  Insulation  materials  of  cables  are  required 
to  be  fire  resistant  and  an  essential  performance 
requirement  is  that  the  insulation  material  may  burn 
or  melt  and  flow  when  directly  exposed  to  a 
temperature  (or  fire)  higher  than  what  it  is  class 
designated  for,  but  should  not  continue  to  burn  after 
the  flame  or  the  source  of  heat  or  file  is  withdrawn. 
Even  if  the  above  fire  resistant  property  is  exhibited 
by  the  cable  insulation,  a  large  collection  of  cables 
will  make  the  cable  insulation  fail  to  exhibit  this 
retardant  property.  While  specific  guidelines  for 
limiting  number  of  cable  and  bunching  is  not 
available  and  in  such  cases  the  switch  over  to  a  bus 
trunking  system  is  the  proper  alternative. 

b)  reduced  maintenance  over  its  entire  lifetime; 

c)  longer  service  lifetime  in  comparison  with  a 
cable  distribution;  and 

d)  enhanced  reliability  due  to  rigid  bolted  joints 
and  tenninations  and  extremely  low  possibility 
of  insulation  failure. 

5.2  System  of  Supply 

5.2.1  All  electrical  apparatus  shall  be  suitable  for  the 
voltage  and  frequency  of  supply. 

5.2.2  In  case  of  connected  load  of  1 00  kVA  and  above, 
the  relative  advantage  of  high  voltage  three-phase 
supply  should  be  considered.  Though  the  use  of  high 
voltage  supply  entails  the  provisions  of  space  and  the 
capital  cost  of  providing  suitable  transfonner  substation 
at  the  consumer’s  premises,  the  following  advantages 
are  gained: 

a)  advantage  in  tariff; 

b)  more  effective  earth  fault  protection  for  heavy 
current  circuits; 

c)  elimination  of  interference  with  supplies  to 
other  consumers  permitting  the  use  of  large 
size  motors,  welding  plant,  etc;  and 

d)  better  control  of  voltage  regulation  and  more 
constant  supply  voltage. 


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NOTE  —  Additional  safety  precautions  required  to  be  observed 
in  HV  installations  shall  also  be  kept  in  view. 

In  many  cases  there  may  be  no  choice  available  to  the 
consumer,  as  most  of  the  licensees  have  formulated  their 
policy  of  correlating  the  supply  voltage  with  the 
connected  load  or  the  contract  demand.  Generally  the 
supply  is  at  240  V  single  phase  up  to  5  kVA, 
415/240  V  3-phase  from  5  kVA  to  100  kVA,  11  kV  (or 
22  kV)  for  loads  up  to  5  MVA  and  33  kV  or  66  kV  for 
consumers  of  connected  load  or  contract  demand  more 
than  5  MVA. 

5.2.3  In  very  large  industrial  buildings  where  heavy 
electric  demands  occur  at  scattered  locations,  the 
economics  of  electrical  distribution  at  high  voltage  from 
the  main  substation  to  other  subsidiary  transformer 
substations  or  to  certain  items  of  plant,  such  as  large 
motors  and  furnaces,  should  be  considered.  The  relative 
economy  attainable  by  use  of  medium  or  high  voltage 
distribution  and  high  voltage  plant  is  a  matter  of  expert 
judgment  and  individual  assessment  in  light  of 
experience  by  a  professionally  qualified  electrical 
engineer. 

5.3  Substation  Equipment  and  Accessories 

Substations  require  an  approval  by  the  Electrical 
Inspectorate.  Such  approval  is  mandatory  before 
energizing  the  substation.  It  is  desirable  to  get  the 
approval  for  the  general  layout,  schematic  layout, 
protection  plan,  etc,  before  the  start  of  the  work  from 
the  Inspectorate.  All  substation  equipment  and 
accessories  and  materials,  etc,  shall  conform  to  relevant 
Indian  Standards,  wherever  they  exist,  otherwise  the 
consumer  (or  his  consultant)  shall  specify  the  standards 
to  which  the  equipment  to  be  supplied  confirms  and 
that  shall  be  approved  by  the  authority.  Manufacturers 
of  equipment  have  to  furnish  certificate  of  conformity 
as  well  as  type  test  certificates  for  record,  in  addition 
to  specified  test  certificates  for  acceptance  tests  and 
installation  related  tests  for  earthing,  earth  continuity, 
load  tests  and  tests  for  performance  of  protective  gear. 

5.3.1  Supply  Company’s  High  Voltage  Meter  Board 

In  case  of  single  point  high  voltage  metering,  energy 
meters  shall  be  installed  in  building  premise  as 
per  4.2.2. 1,  at  such  a  place  which  is  readily  accessible 
to  the  owner/operator  of  the  building  and  the  Authority. 
The  supplier  or  owner  of  the  installation  shall  provide 
at  the  point  of  commencement  of  supply  a  suitable 
isolating  device  fixed  in  a  conspicuous  position  at  not 
more  than  1.7  m  above  the  ground  so  as  to  completely 
isolate  the  supply  to  the  building  in  case  of  emergency. 
In  this  connection,  Central  Electricity  Authority 
(Installation  and  Operation  of  Meters)  Regulations, 
2006,  as  amended  from  time-to-time  shall  be  complied 
with. 


5.3.2  High  Voltage  Switchgear 

5.3.2. 1  The  selection  of  the  type  of  high  voltage 
switchgear  for  any  installation  inter  alia  depends  upon 
the  following: 

a)  Voltage  of  the  supply  system; 

b)  Prospective  short-circuit  current  at  the  point 
of  supply; 

c)  Size  and  layout  of  electrical  installation; 

d)  Accommodation  available;  and 

e)  Nature  of  industry. 

Making  and  breaking  capacity  of  switchgear  shall  be 
commensurate  with  short-circuit  potentialities  of  the 
supply  system  and  the  supply  authority  shall  be 
consulted  on  this  subject.  HV  switchgear  and 
controlgear  shall  conform  to  the  accepted  standards 
[8-2(14)]  and  other  relevant  Indian  Standards. 

5. 3. 2. 2  Guidelines  on  various  types  of  switchgear 
equipment  and  their  choice  for  a  particular  application 
shall  be  in  accordance  with  good  practice  [8-2(12)]. 

5.3.2.3  In  extensive  installations  of  switchgear  (having 
more  than  four  incoming  supply  cables  or  having  more 
than  12  circuit  breakers),  banks  of  switchgears  shall  be 
segregated  from  each  other  in  order  to  prevent  spreading 
of  the  risk  of  damage  by  fire  or  explosion  arising  from 
switch  failure.  Where  a  busbar  section  switch  is  installed, 
it  shall  also  be  segregated  from  adjoining  banks  in  the 
same  way  {see  good  practice  [8-2(13)]}. 

5.3.2.4  It  should  be  possible  to  isolate  any  section  from 
the  rest  of  the  switchboards  such  that  work  might  be 
undertaken  on  this  section  without  the  necessity  of 
making  the  switchboard  dead.  Isolating  switches  used 
for  the  interconnection  of  sections  or  for  the  purpose 
of  isolating  circuit-breakers  of  other  apparatus,  shall 
also  be  segregated  within  its  compartment  so  that  no 
live  part  is  accessible  when  work  in  a  neighbouring 
section  is  in  progress. 

5.3.2. 5  In  the  case  of  double  or  ring  main  supply, 
switchgears  with  interlocking  arrangement  shall  be 
provided  to  prevent  simultaneous  switching  of  two 
different  supply  sources.  Electrical  and/or  mechanical 
interlocks  may  preferably  be  provided. 

5.3.3  HV  Cables 

5.3.3. 1  The  sizing  of  the  cable  shall  depend  upon  the 
method  of  laying  cable,  current  to  be  carried, 
permissible  maximum  temperature  it  shall  withstand, 
voltage  drop  over  the  length  of  the  cable,  the 
prospective  short-circuit  current  to  which  the  cable  may 
be  subjected,  the  characteristics  of  the  overload 
protection  gear  installed,  load  cycle,  thermal  resistivity 
of  the  soil  and  the  operating  voltage  {see  also  good 
practice  [8-2(15)]}. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


31 


53.3.2  All  HV  cables  shall  be  installed  in  accordance 
with  good  practice  [8-2(15)].  The  HV  cables  shall  either 
be  laid  on  the  cable  rack/built-up  concrete  trenches/ 
tunnel/basement  or  directly  buried  in  the  ground 
depending  upon  the  specific  requirement.  When  HV 
cable  is  hanging/running  below  the  basement  ceiling 
slab,  the  cable  shall  be  laid  in  a  fire  rated  enclosure/ 
cable  tray.  The  advice  of  the  cable  manufacturer  with 
regard  to  installation,  jointing  and  sealing  should  also 
be  followed. 

5.3.4  High  Voltage  Bus  Bar  Trunking/Ducting 

HV  bus  bar  system  is  used  for  transporting  power 
between  HV  generators,  transformers  and  the  infeed 
main  switchgear  of  the  main  HV  switchgear. 

Generally  three  types  of  bus  ducts,  namely  non- 
segregated,  segregated  and  isolated  phase  bus  duct 
are  used.  The  non-segregated  bus  ducts  consist  of  three 
phase  bus  bars  running  in  a  common  enclosure  made 
of  steel  or  aluminium.  The  enclosure  shall  provide 
safety  for  the  operational  personnel  and  shall  reduce 
chances  of  faults.  HV  interconnecting  bus  bar  trunking 
for  a.c.  voltage  above  1  kV  up  to  and  including  36  kV 
shall  conform  to  accepted  standard  [8-2(16)].  The 
enclosures  shall  be  effectively  grounded. 

Segregated  phase  bus  ducts  are  similar  to  non- 
segregated  phase  ducts  except  that  metal  or  isolation 
barriers  are  provided  between  phase  conductors  to 
reduce  chances  of  phase  to  phase  faults.  However,  it  is 
preferable  to  use  metal  barriers. 

In  the  case  of  isolated  bus  ducts,  each  phase  conductor 
shall  be  housed  in  a  separate  non-magnetic  enclosure. 
The  bus  duct  shall  be  made  of  sections  which  are 
assembled  together  at  site  to  make  complete  assembly. 
The  enclosure  shall  be  of  either  round  or  square  shape 
and  welded  construction.  The  enclosures  of  all  phases 
in  general  should  be  supported  on  a  common  steel 
structure. 

Seismic  supports  shall  be  provided  for  busbar  trunking 
having  continuous  straight  lengths  of  more  than  24  m 
at  a  single  stretch. 

The  bus  duct  system  shall  be  coordinated  with 
connecting  switchgear  so  as  to  provide  adequate 
protection. 

When  busbar  trunking  is  crossing  different  fire 
compartments,  they  shall  have  fire  barriers  of  same 
rating  as  that  of  the  compartment  (see  also  Part  4  ‘Fire 
and  Life  Safety’  of  the  Code). 

5.3.5  Transformers 

5.3.5. 1  General  design  objective  while  selecting  the 
transformer(s)  for  a  substation  should  be  to  provide  at 
least  two  or  more  transformers,  so  that  a  certain  amount 


of  redundancy  is  built  in,  even  if  a  standby  system  is 
provided.  The  total  installed  transformer  capacity  shall 
be  at  least  1 5  to  20  percent  higher  than  the  anticipated 
maximum  demand.  With  growing  emphasis  on  energy 
conservation,  the  system  design  is  made  for  both 
extremes  of  loading.  During  the  periods  of  lowest  load 
in  the  system,  it  would  be  desirable  to  operate  only  one 
transformer  and  to  subsequently  switch  on  the 
additional  transformers  as  the  load  increases  during  the 
day.  Total  transformer  capacity  is  generally  selected 
on  the  basis  of  present  load,  possible  future  load, 
operation  and  maintenance  cost  and  other  system 
conditions.  The  selection  of  the  maximum  size 
(capacity)  of  the  transformer  is  guided  by  the  short- 
circuit  making  and  breaking  capacity  of  the  switchgear 
used  in  the  medium  voltage  distribution  system. 
Maximum  size  limitation  is  important  from  the  aspect 
of  feed  to  a  downstream  fault.  The  transformers  shall 
conform  to  accepted  standards  [8-2(17)]  and  other 
relevant  Indian  Standards. 

53.5.2  For  reasons  of  reliability  and  redundancy  it  is 
normal  practice  to  provide  at  least  two  transformers 
for  any  important  installation.  Interlinking  by  tie  lines 
is  an  alternative  to  enhance  reliability/redundancy  in 
areas  where  there  are  a  number  of  substations  in  close 
vicinity,  such  as  a  campus  with  three  or  four  multi¬ 
storeyed  blocks,  each  with  a  substation.  Ring  main  type 
of  distribution  is  preferred  for  complexes  having  a 
number  of  substations. 

5.3.6  Medium  or  Low  Voltage  Switchgear  and 
Controlgear  and  their  Assemblies 

53.6.1  The  selection  of  the  type  of  medium  or  low 
voltage  switchgear  for  any  installation  inter  alia 
depends  upon  the  following: 

a)  Voltage  of  the  distribution  system; 

b)  Prospective  circuit  current  at  the  point  at 
which  the  switchgear  is  proposed; 

c)  Prospective  short-circuit  current  at  which  the 
switchgear  is  proposed; 

d)  Accommodation  available;  and 

e)  Nature  of  industry. 

The  switchgear  and  controlgear  and  their  assemblies 
so  selected  shall  comply  with  the  relevant  accepted 
standards  [8-2(18)],  other  relevant  Indian  Standards, 
IEC  61439  (Part  1) :  201 1  ‘Low- voltage  switchgear  and 
controlgear  assemblies  —  Part  1:  General  rules’  ( under 
publication  as  adopted  Indian  Standard)  and  IEC  61439 
(Part  2):  2011  ‘Low-voltage  switchgear  and  controlgear 
assemblies  —  Part  2:  Power  switchgear  and  controlgear 
assemblies’  ( under  publication  as  adopted  Indian 
Standard). 

53.6.2  Switchgear  (and  its  protective  device)  shall 


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have  breaking  capacity  not  less  than  the  anticipated 
fault  level  in  the  system  at  that  point.  System  fault 
level  at  a  point  in  distribution  systems  is 
predominantly  dependent  on  the  transformer  size  and 
its  reactance.  Parallel  operation  of  transformers 
increases  the  fault  level. 

5.3. 6. 3  Where  two  or  more  transformers  are  to  be 
installed  in  a  substation  to  supply  a  medium  voltage 
distribution  system,  the  distribution  system  shall  be 
divided  into  separate  sections,  each  of  which  shall  be 
normally  fed  from  one  transformer  only  unless  the 
medium  voltage  switchgear  has  the  requisite  short- 
circuit  capacity.  Provision  may,  however,  be  made  to 
interconnect  separate  sections,  through  a  bus  coupler 
in  the  event  of  failure  or  disconnection  of  one 
transformer.  See  4.2  for  details  of  location  and 
requirements  of  substation. 

5.3. 6.4  Isolation  and  controlling  circuit  breaker  shall 
be  interlocked  so  that  the  isolator  cannot  be  operated 
unless  the  corresponding  breaker  is  in  open  condition. 
The  choice  between  alternative  types  of  equipment 
may  be  influenced  by  the  following  considerations: 

a)  In  certain  installations  supplied  with  electric 
power  from  remote  transformer  substations, 
it  may  be  necessary  to  protect  main  circuits 
with  circuit-breakers  operated  by  earth  fault, 
in  order  to  ensure  effective  earth  fault 
protection. 

b)  Where  large  electric  motors,  furnaces  or 
other  heavy  electrical  equipment  is  installed, 
the  main  circuits  shall  be  protected  from 
short-circuits  by  switch  disconnector  fuse  or 
circuit  breakers.  For  motor  protection,  the 
combination  of  contactor  overload  device 
and  fuse  or  circuit  breakers  shall  have  total 
coordination  at  least  for  motor  ratings  up  to 
10  kW,  and  for  ratings  above  10  kW,  it  shall 
be  Type  2  coordination  in  accordance  with 
relevant  part  of  accepted  standards  [8-2(18)]. 
Wherever  necessary,  back  up  protection  and 
earth  fault  protection  shall  be  provided  to  the 
main  circuit. 

c)  Where  means  of  isolating  main  circuits  is 
separately  required,  switch  disconnector  fuse 
or  switch  disconnector  may  form  part  of  main 
switchboards. 

5.3. 6.5  It  shall  be  mandatory  to  provide  power  factor 
improvement  capacitor  at  the  substation  bus.  Suitable 
capacitor  may  be  selected  in  consultation  with  the 
capacitor  as  well  as  switchgear  manufacture 
depending  upon  the  nature  of  electrical  load 


anticipated  on  the  system.  Necessary  switchgear/ 
feeder  circuit  breaker  shall  be  provided  for  controlling 
of  capacitor  bank. 

Power  factor  of  individual  motor  may  be  improved 
by  connecting  individual  capacitor  banks  in  parallel. 
For  higher  range  of  motors,  which  are  running 
continuously  without  much  variation  in  load, 
individual  power  factor  correction  at  load  end  is 
advisable. 

NOTE  —  Care  should  be  taken  in  deciding  the  kVAr  rating 
of  the  capacitor  in  relation  to  the  magnetizing  kVA  of  the 
motor.  Over  rating  of  the  capacitor  may  cause  injury  to  the 
motor  and  capacitor  bank.  The  motor  still  rotating  after 
disconnection  from  the  supply,  may  act  as  generator  by  self¬ 
excitation  and  produce  a  voltage  higher  than  supply  voltage. 
If  the  motor  is  again  switched  on  before  the  speed  has  fallen 
to  about  80  percent  of  the  normal  running  speed,  the  high 
voltage  will  be  superimposed  on  the  supply  circuits  and  will 
damage  both  the  motor  and  the  capacitor. 

As  a  general  rule,  the  kVAr  rating  of  the  capacitor 
should  not  exceed  the  no-load  magnetizing  kVA  of 
the  motor. 

Generally  it  will  be  necessary  to  provide  an  automatic 
control  for  switching  on  the  capacitors  matching  the 
load  power  factor  and  the  bus  voltage.  Such  a  scheme 
will  be  necessary  as  capacitors  permanently  switched 
in  the  circuit  may  cause  over  voltage  at  times  of  light 
load.  Capacitor  panel  shall  be  provided  with  adequate 
ventilation  facility. 

5. 3. 6. 6  Harmonics  on  the  supply  systems  are 
becoming  a  greater  problem  due  to  the  increasing  use 
of  electronic  equipment,  computer,  fluorescent  lamps, 
LEDs  and  CFLs  (both  types  have  control/driver 
circuits  operating  in  switch  mode),  mercury  vapour 
and  sodium  vapour  lighting,  TV,  microwave  ovens, 
latest  air  conditioners,  refrigerators,  controlled 
rectifier  and  inverters  for  variable  speed  drives,  power 
electronics  and  other  non-linear  loads.  Harmonics  may 
lead  to  almost  as  much  current  in  the  neutral  as  in  the 
phases.  This  current  is  almost  third,  fifth,  seventh  and 
ninth  harmonic.  In  such  cases,  phase  rectification 
devices  may  be  considered  at  the  planning  stage  itself 
for  the  limits  of  harmonic  voltage  distortion. 

With  the  wide  spread  use  of  thyristor  and  rectifier 
based  loads,  there  is  a  necessity  of  providing  a  full 
size  neutral;  but  this  requirement  is  generally  limited 
to  the  3-phase  4-wire  distribution  generally  in 
the  415/240  V. 

5.3. 6.7  MV/LV Bus  bar  chambers 

Bus  bar  chambers,  which  feed  two  or  more  circuits, 
shall  be  controlled  by  a  main  disconnector  (TP&N) 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


33 


or  TPN  MCB  to  enable  them  to  be  disconnected  from 
the  supply. 

5. 3. 6. 8  Sufficient  clearances  as  below  shall  be 
provided  for  isolating  the  switchboard  to  allow  access 
for  servicing,  testing  and  maintenance  (see  Fig.  2): 

a)  A  clear  space  of  not  less  than  1  m  in  width 
shall  be  provided  in  front  of  the  switchboard. 

NOTE  —  In  case  the  board  has  a  shutter  in  the 
front  for  aesthetic  reasons,  provided  the  opening 
of  the  shutter  shall  satisfy  the  requirement  of 
working/safety  space  of  1  m  in  front  of  the 
switchgear. 

b)  If  there  are  any  attachments  or  bare 
connections  at  the  back  of  the  switchboard, 
the  space,  if  any,  behind  the  switchboard  shall 
be  either  less  than  200  mm  or  more  than 
750  mm  in  width,  measured  from  the  farthest 
protruding  part  of  any  attachment  or 
conductor. 

c)  If  the  space  behind  the  switchboard  exceeds 
750  mm  in  width,  there  shall  be  a  passageway 
from  either  end  of  the  switchboard,  clear  to 
a  height  of  1.8  m. 

d)  If  two  switchboards  are  facing  each  other,  a 
minimum  distance  of  2.0  m  shall  be 
maintained  between  them. 

The  connections  between  the  switchgear  mounting  and 
the  outgoing  cable  up  to  the  wall  shall  be  enclosed  in 
a  protection  pipe. 


There  shall  be  a  clear  distance  of  not  less  than  250  mm 
between  the  board  and  the  insulation  cover,  the 
distance  being  increased  for  larger  boards  in  order 
that  on  closing  of  the  cover,  the  insulation  of  the  cables 
is  not  subjected  to  damage  and  no  excessive  twisting 
or  bending  in  any  case.  The  cable  alley  in  the  metal 
board  should  enable  within  prescribed  limit  twisting 
or  bending  of  cable  such  that  insulation  of  the  cables 
is  not  subjected  to  damage. 

In  this  connection,  for  installation  of  voltages 
exceeding  250  V,  Regulation  37  of  Central  Electricity 
Authority  (Measures  Relating  to  Safety  and  Electricity 
Supply)  Regulations,  2010,  as  amended  from  time- 
to-time  shall  also  be  complied  with  (see  Annex  B). 

5.3. 6. 9  Sufficient  additional  space  shall  be  allowed 
in  substations  and  switchrooms  to  allow  operation  and 
maintenance.  Sufficient  additional  space  shall  be 
allowed  for  temporary  location  and  installation  of 
standard  servicing  and  testing  equipment.  Space 
should  also  be  provided  to  allow  for  anticipated  future 
extensions. 

5.3.6.10  Panels  in  a  room  or  cubicle  or  in  an  area 
surrounded  by  wall/fence,  access  to  which  is 
controlled  by  lock  and  key  shall  be  accessible  to 
authorized  persons  only. 

Such  installations  shall  be  efficiently  protected  by 
fencing  not  less  than  1  800  mm  in  height  or  other  means 
so  as  to  prevent  access  to  the  electric  supply  lines  and 
apparatus  therein  by  an  undesignated  person  and  the 


ENTRY /EXIT 
OF  EQUIPMENT /PANEL 
AND  AUTHORIZED  PERSON 


2A  ONE  SWITCH  BOARD/PANEL 


2B  TWO  SWITCH  BOARDS/PANELS  FACING  EACH  OTHER 


X  =  Less  than  200  mm  (if  switchboard/panel  is 
not  accessible  from  behind) 

=  More  than  750  mm  (if  switchboard/panel  is 
accessible  from  behind) 

NOTE  —  X  to  be  measured  from  the  fathest  protruding  part  of  any  attachment  or  conductor. 

Fig.  2  Clearances  around  Switchboards  In  Enclosed  Room 


34 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


fencing  of  such  area  shall  be  earthed  efficiently. 
Sufficient  clearances  as  per  5.3.6.8  shall  be  provided 
between  the  switchboard  and  the  wall/fence. 

5.3.6.11  Except  main  LV  panel,  it  will  be  preferable  to 
locate  the  sub-panels/distribution  boards/sub-meter 
boards  near  the  load  centre.  Further,  it  should  be 
ensured  that  these  panels  are  easily  approachable.  The 
panels  should  have  clear  access  from  common  areas 
excluding  staircase. 

Where  the  switchboard  is  erected  in  a  room  of  a  building 
isolated  from  the  source  of  supply  or  at  a  distance  from 
it,  adequate  means  of  control  and  isolation  shall  be 
provided  both  near  the  boards  and  at  the  origin  of 
supply.  Sufficient  clearances  as  per  5.3. 6.8  shall  be 
provided. 

5.3.6.12  All  switchboards  shall  be  of  metal  clad  totally 
enclosed  type  or  any  insulated  enclosed  pattern. 

5.3.7  Medium  or  Low  Voltage  Cables 

5.3.7. 1  The  sizing  of  the  cable  shall  depend  upon  the 
current  to  be  carried,  method  of  laying  cable, 
permissible  maximum  temperature  it  shall  withstand, 
voltage  drop  over  the  length  of  the  cable,  the 
prospective  short-circuit  current  to  which  the  cable  may 
be  subjected,  the  characteristics  of  the  overload 
protection  gear  installed,  load  cycle,  thermal  resistivity 
of  the  soil  and  the  operating  voltage  {see  also  good 


practice  [8-2(11)]}. 

It  is  desirable  to  use  flame  retardant  cables  and  wires 
in  electrical  distribution  systems.  Availability  of  flame 
retardant  low  smoke  and  halogen  cable  may  also  be 
noted  and  considered  accordingly. 

It  is  recommended  to  use  four  core  cable  in  place  of 
three  and  half  core  to  minimize  heating  of  neutral  core 
due  to  harmonic  content  in  the  supply  system  and  also 
avoidance  of  overload  failures.  All  cables  shall  be 
installed  in  accordance  with  good  practice  [8-2(11)]. 
The  advice  of  the  cable  manufacturer  with  regard  to 
installation,  jointing  and  sealing  should  also  be 
followed. 

In  final  circuits  where  cable  size  of  16  mm2  and  below 
are  used,  these  shall  be  4  core  cables  only  to  avoid  the 
possibility  of  neutral  overload,  (except  for  equipment 
such  as  motors,  heaters  which  offer  balanced  3  phase 
load  and  do  not  require  a  neutral  connection.  As  a  result 
it  is  not  desirable  to  use  half-size  neutral  conductor  as 
possibility  of  neutral  conductor  overload  due  to 
harmonics  is  likely.  Larger  feeders  (size  greater  than 
16  mm2)  may  revert  to  use  3 14  core  cables. 

5.3. 7.2  Colour  identification  of  cores  of  non-flexible 
cables  {see  also  good  practice  [8-2(19)]} 

The  colour  of  cores  of  non-flexible  cables  shall  be  in 
accordance  with  the  following: 


SI 

No. 

(1) 

Function 

(2) 

Colour  Identification  of  Core  of  Rubber  of 
PVC  Insulated  Non-flexible  Cable,  or  of 
Sleeve  or  Disc  to  be  Applied  to  Conductor 
or  Cable  Code 

(3) 

i) 

Protective  or  earthing 

Green  and  yellow  ( see  Note  1 ) 

ii) 

Phase  of  a.c.  single-phase  circuit 

Red  [or  yellow  or  blue  ( see  Note  2)] 

iii) 

Neutral  of  a.c.  single  or  three-phase  circuit 

Black 

iv) 

Phase  R  of  3-phase  a.c.  circuit 

Red 

v) 

Phase  Y  of  3-phase  a.c.  circuit 

Yellow 

VI) 

Phase  B  of  3-phase  a.c.  circuit 

Blue 

vii) 

Positive  of  d.c.  2-wire  circuit 

Red 

viii) 

Negative  of  d.c.  2-wire  circuit 

Black 

IX) 

Outer  (positive  or  negative)  of  d.c. 

2-wire  circuit 

Red 

derived  from  3 -wire  system 

X) 

Positive  of  3 -wire  system  (positive 

of  3-wire  d.c. 

Red 

circuit) 

XI) 

Middle  wire  of  3-wire  d.c.  circuit 

Black 

xii) 

Negative  of  3-wire  d.c.  circuit 

Blue 

xiii) 

Functional  earth-telecommunication 

Cream 

NOTES 

1  Bare  conductors  are  also  used  for  earthing  and  earth  continuity  conductors 

.  But  it  is  preferable  to  use  insulated  conductors  with 

green  coloured  insulation  with  yellow  stripes. 

2  As  alternative  to  the  use  of  red,  yellow  or  blue  colour  may  be  used,  if  desired 

in  large  installations,  up  to  the  final  distribution  board. 

3  For  armoured  PVC-insulated  cables  and  paper-insulated  cables,  see  relevant  Indian  Standard. 

PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


35 


5.3. 7.3  Colour,  identification  of  cores  of  flexible  cables 
and  flexible  cords  {see  also  good  practice  [8-2(19)]} 


The  colour  of  cores  of  flexible  cables  and  flexible  cords 
shall  be  in  accordance  with  the  following: 


SI 

No. 

(1) 

Number 

of 

Cores 

(2) 

Function  of 
Core 

(3) 

Colour(s)  of 
Core 

(4) 

i) 

1 

Phase 

Neutral 

Protective  or 
earthing 

Brown1 1 
(Light)  Blue 

Green  and 
yellow 

ii) 

2 

Phase 

Neutral 

Brown 
(Light)  Blue11 

iii) 

3 

Phase 

Neutral 
Protective  or 
earthing 

Brown 
(Light)  Blue11 
Green  and 
yellow 

iv) 

4  or  5 

Phase 

Neutral 
Protective  or 
earthing 

Brown  or 
black11 

(Light)  Blue11 
Green  and 
yellow 

Certain  alternatives  are  allowed  in  wiring  regulations. 

5.3.8  MV/LV Bus  bar  Trunking/Rising  Mains 

5.3.8. 1  Where  heavy  loads  and/or  multiple  distribution 
feeders  are  required  to  be  supplied,  busbar/rising  main 
systems  are  preferred.  The  busbars  are  available  for 
continuous  run  from  point  to  point  or  with  tap  offs  at 
standard  intervals  and  have  to  be  chosen  as  per  specific 
requirement.  Seismic  supports  shall  be  provided  for  bus 
trunking  having  continuous  straight  lengths  of  more  than 
24  m  at  a  single  stretch.  There  are  following  two  types 
of  MV/LV  bus  duct  systems  for  power  distribution: 

a)  Conventional  type;  and 

b)  Compact  and  sandwich  type. 

5.3. 8. 1.1  Conventional  type  bus  duct 

These  are  used  for  large  power  handling  between 
transformer  and  switchgear  or  between  switchgear  and 
large  power  loads  such  as  compressor  drive  motor,  etc. 
This  type  is  generally  used  in  plant  rooms,  riser  shafts, 
substations,  etc.  These  are  generally  air  insulated  with 
intermediate  ceramic  support  insulators  enclosed  in  a 
metallic  enclosure,  which  should  be  earthed.  They  have 
the  least  amount  of  combustible  material.  However, 
when  these  are  crossing  different  fire  compartments, 
they  shall  have  fire  barriers  of  same  rating  as  that  of 
the  compartment  ( see  also  Part  4  ‘Fire  and  Life  Safety’ 
of  the  Code). 


Conventional  type  bus  ducts  with  non-metallic 
enclosures  are  also  available.  However,  such  bus  ducts 
shall  be  used  only,  if  essential  and  with  appropriate 
additional  care. 

5.3. 8. 1.2  Compact  type  bus  duct 

Compact  type  bus  ducts  are  used  within  areas  of  the 
building  which  have  space  restrictions,  etc,  for  aesthetic 
and  functional  reasons.  These  are  either  air  insulated 
or  sandwich  type.  They  may  be  used  in  false  ceiling 
spaces  or  even  in  corridors  and  shafts  for  distribution 
without  any  false  ceiling  as  they  provide  an  aesthetically 
acceptable  finish  to  merge  with  other  building  elements 
such  as  beams,  ducts  or  pipes  in  functional  buildings. 

The  insulation  material  in  such  ducts  are  generally  glass 
fibre  tape  or  epoxy  encapsulation  in  combination  with 
ceramic  supports/spacers.  These  bus  ducts  should  be 
duly  enclosed  by  a  metallic  enclosure,  which  should 
be  earthed. 

In  case  of  compact  air  insulated  type  bus  ducts  crossing 
different  fire  compartments,  they  shall  have  fire  barriers 
of  same  rating  as  that  of  the  compartment  (see  also 
Part  4  ‘Fire  and  Life  Safety’  of  the  Code). 

5.3.8.2  The  bus  duct  system  shall  be  coordinated  with 
connecting  switchgear  so  as  to  provide  adequate 
protection. 

5.3. 8.3  Seismic  supports  shall  be  provided  for  busbar 
trunking  having  continuous  straight  lengths  of  more 
than  24  m  at  a  single  stretch. 

5.3. 8. 4  Where  the  number  of  individual  units/flats/ 
shops/offices  on  a  floor  in  a  building  are  more  than  24, 
multiple  rising  mains  are  recommended  for  power 
distribution. 

5.3.8.5  The  low  voltage  bus  bar  trunking  shall  conform 
to  accepted  standard  [8-2(20)]. 

5.4  Reception  and  Distribution  of  Main  Supply 

5.4.1  Control  at  Point  of  Commencement  of  Supply 

5.4. 1.1  The  supplier  shall  provide  a  suitable  metering 
switchgear  in  each  conductor  of  every  service  line  other 
than  an  earthed  or  earth  neutral  conductor  or  the  earthed 
conductor  of  a  concentric  cable  within  a  consumer’s 
premises,  in  an  accessible  position  and  such  metering 
switchgear  shall  be  contained  within  adequately 
enclosed  fireproof  receptacle.  Where  more  than  one 
consumer  is  supplied  through  a  common  service  line, 
such  consumer  shall  be  provided  with  an  independent 
metering  switchgear  at  the  point  of  rigid  junction  to 
the  common  service.  Every  electric  supply  line  other 
than  the  earthed  or  earthed  neutral  conductor  of  any 
system  or  the  earthed  external  conductor  of  a  concentric 
cable  shall  be  protected  by  a  suitable  switchgear  by  its 


36 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


owner.  In  this  connection,  Regulation  14  and  41  of 
Central  Electricity  Authority  (Measures  Relating  to 
Safety  and  Electricity  Supply)  Regulations,  2010,  as 
amended  from  time-to-time  shall  also  be  complied  with 
(see  Annex  B). 

In  case  of  high  rise  buildings,  the  supplier  or  owner  of 
the  installation  shall  provide  at  the  point  of 
commencement  of  supply  a  suitable  isolating  device 
with  cut-out  or  breaker  to  operate  on  all  phases  except 
neutral  in  the  3-phase,  4-wire  circuit  and  fixed  in  a 
conspicuous  position  at  not  more  than  1.7  m  above  the 
ground  so  as  to  completely  isolate  the  supply  to  the 
building  in  case  of  emergency.  In  this  connection, 
Regulation  36  of  Central  Electricity  Authority 
(Measures  Relating  to  Safety  and  Electricity  Supply) 
Regulations,  20 1 0,  as  amended  from  time-to-time  shall 
also  be  complied  with  (see  Annex  B). 

The  supplier  shall  provide  and  maintain  on  the 
consumer’s  premises  for  the  consumer’s  use,  a  suitable 
earthed  terminal  in  an  accessible  position  at  or  near 
the  point  of  commencement  of  supply.  In  this 
connection,  Regulation  16  of  Central  Electricity 
Authority  (Measures  Relating  to  Safety  and  Electricity 
Supply)  Regulations,  2010,  as  amended  from  time-to- 
time  shall  also  be  complied  with  (see  Annex  B). 

No  cut-out,  link  or  switch  other  than  a  linked  switch 
arranged  to  operate  simultaneously  on  the  earthed  or 
earthed  neutral  conductor  and  live  conductor  shall  be 
inserted  or  remain  inserted  in  any  earthed  or  earthed 
neutral  conductor  of  a  two  wire-system  or  in  any  earthed 
or  earthed  neutral  conductor  of  a  multi-wire  system  or 
in  any  conductor  connected  thereto.  This  requirement 
shall  however  not  apply  in  case  of, 

a)  a  link  for  testing  purposes,  or 

b)  a  switch  for  use  in  controlling  a  generator  or 
transformer. 

In  this  connection.  Regulation  15  (ii)  of  Central 
Electricity  Authority  (Measures  Relating  to  Safety  and 
Electricity  Supply)  Regulations,  20 1 0,  as  amended  from 
time-to-time  shall  also  be  complied  with  (see  Annex  B). 

The  neutral  shall  also  be  distinctly  marked. 

5.4. 1.2  The  main  switch  shall  be  easily  accessible  and 
situated  as  near  as  practicable  to  the  termination  of 
service  line. 

5.4. 1.3  Where  the  conductors  include  an  earthed 
conductor  of  a  two-wire  system  or  an  earthed  neutral 
conductor  of  a  multi-wire  system  or  a  conductor  which 
is  to  be  connected  thereto,  an  indication  of  a  permanent 
nature  shall  be  provided  for  identification  in  accordance 
with  Regulation  15  (i)  of  Central  Electricity  Authority 
(Measures  Relating  to  Safety  and  Electricity  Supply) 
Regulations,  2010,  as  amended  from  time-to-time  (see 
Annex  B). 


5.4. 1.4  Energy  meters 

5. 4. 1.4.1  Energy  meters  conforming  to  accepted 
standards  [8-2(2 1 )]  and  other  relevant  Indian  Standards 
shall  be  installed  in  all  buildings  at  such  a  place  which 
is  readily  accessible  to  the  owner/operator/occupant  of 
the  building  and  the  Authority.  Meters  should  not  be 
located  at  an  elevated  area  or  a  depressed  area  that  does 
not  have  access  by  means  of  a  stairway  of  normal  rise. 
The  height  of  meter  display  shall  be  between  750  mm 
and  1  800  mm.  In  case  the  meter  is  provided  with  a 
secondary  display  unit,  this  requirement  applies  to  the 
secondary  display  unit  only.  A  minimum  clearance  of 
50  mm  should  be  maintained  around  the  meter  itself 
for  better  inspection.  This  includes  the  space  between 
two  meters,  or  between  meter  and  the  mounting  box, 
or  between  two  mounting  boxes  as  the  case  may  be. 
The  energy  meters  should  either  be  provided  with  a 
protecting  covering,  enclosing  it  completely  except  the 
glass  window  through  which  the  readings  are  noted  or 
should  be  mounted  inside  a  completely  enclosed  panel 
provided  with  hinged  arrangement  for  locking. 
Additionally,  for  outdoor  installations,  the  meters  and 
associated  accessories  shall  be  protected  by  appropriate 
enclosure  of  level  of  protection  IP  55  and  ensuring 
compliance  with  above  conditions.  The  enclosure 
should  preferably  be  light  coloured. 

In  large  multi-storeyed  buildings,  installation  of  a  large 
number  of  energy  meters  at  the  ground  floor  (or  first 
basement)  switch-room  for  the  convenience  of  the 
meter-reader  poses  high  fire  hazard.  More  than  24 
energy  meters  on  one  switchboard  is  undesirable.  In 
such  cases,  where  number  of  energy  meters  to  be 
installed  for  feeding  exceeds  24,  energy  meters  shall 
be  installed  at  each  floor  and  therefore,  the  rising  main 
(bus  trunking)  with  tapping  point  at  individual  floor 
shall  be  provided  for  meters. 

The  energy  meters  shall  be  protected  by  suitable  circuit 
breaker.  The  provisions  of  5.3. 6.8  shall  apply  in  case 
of  energy  meters  installed  in  boards. 

5.4. 1.4.2  Main  sources  of  energy,  as  given  below  shall 
be  metered,  as  required  at  entry  into  the  premise/control 
panel: 

1)  Utility  grid  points  (high  voltage/medium 
voltage/low  voltage), 

2)  Captive  generator  sets,  and 

3)  On-site  renewable  energy  system  (if  installed/ 
operational). 

5.4. 1.4.3  Testing,  evaluation,  installation  and 
maintenance  of  energy  meters  shall  be  in  accordance 
with  the  good  practice  [8-2(22)]. 

5.4.1.4.4  Centralized  metering  system 

Smart  metering  and  energy  monitoring  in  a  centralized 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


37 


metering  system  are  used  to  monitor,  measure,  and 
control  the  demand  of  electrical  loads  in  a  building.  These 
systems  are  designed  specifically  for  the  control  and 
monitoring  of  those  facilities  in  a  building  which  have 
significant  electrical  consumption,  such  as  heating, 
ventilation,  air  conditioning,  lifts,  pumps,  and  lighting 
installations  at  multiple  locations  in  a  campus.  The  scope 
may  span  from  a  single  building  to  a  group  of  buildings, 
such  as  residential  apartments  under  common  ownership, 
large  multi-storeyed  buildings,  malls,  university 
campuses,  office  buildings,  retail  store  networks, 
factories,  or  any  building  with  multi-tenanted  occupancy. 
These  systems  provide  metering,  submetering  and 
monitoring  functions  to  allow  facility  and  building 
managers  to  gather  data  and  insight  that  allow  them  to 
make  more  informed  decisions  about  demand 
management  and  demand  control  across  their  sites. 

For  such  buildings  with  centralized  metering,  several 
main  meters  and  sub-meters  with  following 
requirements  should  be  provided: 

a)  Main  meters  should  be  digital  energy  meters 
with  high  accuracy,  high  sampling  rates  and 
power  quality  parameters,  that  is,  harmonics, 
etc,  for  meters  installed  at  incomer  level. 

b)  Separate  sub-meters  should  be  provided  for 
all  energy  end  uses  and  functional  areas  that 
individually  account  for  reasonable  energy 
consumption  in  the  building.  These  may 
include,  but  are  not  limited  to,  sub-meters  for 
HVAC  system;  common  area  lighting,  raw 
power,  UPS,  other  common  utility;  lifts  and 
escalators,  pumps,  external  and  internal 
lighting,  individual  units/flats/shops/  offices; 
etc. 

c)  The  sub-meters  should  be  able  to 
communicate  data  for  monitoring.  At  a 
minimum,  the  sub-metering  infrastructure 
should  facilitate  the  aggregation  of  total 
energy  use. 

d)  Adequate  smart  metering  and  energy 
monitoring  infrastructure  should  be  installed 
in  order  to  help  monitor  operational  energy 
use  and  costs  and  to  enable  continuous  energy 
performance  improvement. 

Smart  metering  and  energy  monitoring  system  that  can 
display  the  following  parameters  should  be  installed 
with  two-way  communicable  smart  meters: 

1 )  Hourly  energy  demand  and  use; 

2)  Energy  breakdown  and  mix  and  energy 
consumption  patterns; 

3)  Power  quality  analysis; 

4)  Energy  consumption  by  process,  department, 
building,  floor,  etc; 


5)  Comparison  of  actual  energy  use  with  targets 
or  historical  trends  and  benchmark  energy  key 
performance  indicators;  and 

6)  Reporting  on  energy  efficiency  achieved. 

These  systems  should  also  have  the  ability  to  utilize 
near-real-time  or  time-of-use  pricing  through 
integration  of  smart  meters  with  the  monitoring  and 
control  system.  The  system  should  be  capable  of 
supporting  predictive  demand  for  better  demand 
management  and  proactive  demand  control. 

5.4.1.4.5  The  Central  Electricity  Authority  (Installation 
and  Operation  of  Meters)  Regulations  2006,  as 
amended  from  time-to-time  shall  also  be  complied  with. 

5.4.2  Main  Switches  and  Switchboard 

5.4.2. 1  All  main  switches  shall  be  either  of  metal-clad 
enclosed  pattern  or  of  any  insulated  enclosed  pattern 
which  shall  be  fixed  at  close  proximity  to  the  point  of 
entry  of  supply.  Every  switch  shall  have  suitable  ingress 
protection  level  rating  (IP),  so  that  its  operation  is 
satisfactory  and  safe  in  the  environment  of  the 
installation. 

NOTE  —  Woodwork  shall  not  be  used  for  the  construction  or 
mounting  of  switches  and  switch  boards  installed  in  a  building. 

5.4.2.2  Location 

The  main  switchboard  shall  comply  with  the  following 
requirements  relating  to  its  location: 

a)  The  location  of  the  main  board  should  be  such 
that  it  is  easily  accessible  to  firemen  and  other 
personnel  to  quickly  disconnect  the  supply  in 
case  of  emergencies.  If  the  room  is  locked  for 
security  reasons,  means  of  emergency  access, 
by  schemes  such  as  break  glass  cupboard, 
shall  be  incorporated. 

b)  Main  switch  board  shall  be  installed  in  rooms 
or  fire  safe  cupboards  so  as  to  safeguard 
against  operation  by  unauthorized  personnel. 
Otherwise  the  main  switch  board  shall  have 
lock  and  key  facility  for  small  installations  in 
residences  or  other  occupancies  having 
sanctioned  loads  less  than  5  kW. 

c)  Switchboards  shall  be  placed  only  in  dry 
situations  and  in  ventilated  rooms  and  they 
shall  not  be  placed  in  the  vicinity  of  storage 
batteries  or  exposed  to  chemical  fumes. 

d)  In  damp  situation  or  where  inflammable  or 
explosive  dust,  gas  or  vapour  is  likely  to  be 
present,  the  switchboard  shall  be  totally 
enclosed  and  shall  have  adequate  degree  of 
ingress  protection  (IP).  In  some  cases 
flameproof  enclosure  may  be  necessitated  by 
particular  circumstances  [see  8-2(23)]. 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


e)  Switchboards  shall  not  be  erected  above  gas 
stoves  or  sinks,  or  within  2.5  m  of  any  washing 
unit  in  the  washing  rooms  or  laundries,  or  in 
bathrooms,  lavatories  or  toilets,  or  kitchens. 

f)  In  case  of  switchboards  unavoidably  fixed  in 
places  likely  to  be  located  outdoors,  exposed 
to  weather,  to  drip,  or  to  abnormal  moist 
temperature,  the  outer  casing  shall  be 
weatherproof  and  shall  be  provided  with 
glands  or  bushings  or  adopted  to  receive 
screwed  conduit,  according  to  the  manner  in 
which  the  cables  are  run.  The  casing  as  well 
as  cable  entries  shall  have  suitable  IP  ratings 
according  to  the  installation. 

g)  Adequate  illumination  shall  be  provided  for 
all  working  spaces  around  the  switchboards. 

h)  Easy  access  to  the  enclosure  around 
switchgear  is  essential  to  enable  easy  and  safe 
operation  and  maintenance.  The  provisions  as 
given  in  5.3.6.8  including  requirements  for 
sufficient  clearances  shall  be  complied  with. 

5.4.2.3  Metal-clad  switchgear  shall  be  mounted  on  any 
of  the  following  types  of  boards: 

a)  Hinged-type  metal  boards  —  These  shall 
consist  of  a  box  made  of  sheet  metal  not  less 
than  2  mm  thick  and  shall  be  provided  with  a 
hinged  cover  to  enable  the  board  to  swing 
open  for  examination  of  the  wiring  at  the  back. 
The  board  shall  be  securely  fixed  to  the  wall 
by  means  of  proper  nuts  and  bolts  designed 
to  take  weight  of  the  switch  board  and  shall 
be  provided  with  a  locking  arrangement  and 
an  earthing  and  neutral  stud  or  bus.  All  wires 
passing  through  the  metal  board  shall  be 
protected  by  cable  termination  glands  at  the 
entry  hole.  The  earth  stud  should 
commensurate  with  the  size  of  earth  lead/ 
leads.  Alternatively,  metal  boards  may  be 
made  of  suitable  size  iron  angle  section  of 
minimum  size  35  mm  x  35  mm  x  6  mm  or 
iron  channel  section  of  minimum  size  35  mm 
x  25  mm  x  6  mm  frame  work  suitably  mounted 
on  front  with  a  3  mm  thick  mild  steel  plate 
and  on  back  with  1.5  mm  thick  mild  steel 
sheet.  No  apparatus  shall  project  beyond  any 
edge  of  panel.  No  fuse  body  shall  be  mounted 
within  25  mm  of  any  edge  of  the  panel. 

NOTE  —  Such  type  of  boards  are  particularly 
suitable  for  small  switchboard  for  mounting  metal- 
clad  switchgear  connected  to  supply  at  low  voltages. 

b)  Fixed-type  metal  boards  —  These  shall 
consist  of  an  angle  or  channel  iron  frame  fixed 
on  the  wall  or  on  floor  and  supported  on  the 
wall  at  the  top,  if  necessary. 


NOTE  —  Such  type  of  boards  are  suitable  for  both 
small  and  large  switchboards.  They  are  particularly 
suitable  for  large  switchboards  for  mounting  number 
of  switchgears  or  high  capacity  metal-clad 
switchgear  or  both  in  an  arrangement  which  do  not 
require  rear  access. 

c)  Protected-type  switchboard  —  A  protected 
switchboard  is  one  where  all  of  the  switchgear 
and  conductors  are  protected  by  metal  or 
halogen  free  plastic  enclosures.  They  may 
consist  of  a  metal/plastic  cubicle  panel,  or  an 
iron  frame  upon  which  metal-clad  switchgears 
are  mounted.  They  usually  consist  of  a  main 
switch,  bus  bars  and  circuit  breakers  or  fuses 
controlling  outgoing  circuits. 

d)  Outdoor-type  switchboard — An  outdoor-type 
switchboard  is  one  which  is  totally  enclosed 
and  UV  ray  protected  and  having  high  ingress 
protection  against  dust  and  moisture  and 
vermin-proof  and  high  impact  resistance 
(IP  55  or  higher  and  IK  10).  Such 
switchboards  are  of  cubicle  type  and  also 
provide  high  impact  resistance.  Cubicle  type 
boards  shall  be  with  hinged  doors  interlocked 
with  switch-operating  mechanisms.  The  doors 
of  these  switchboards  shall  have  facility  to 
ensure  that  it  is  always  in  closed  conditions. 
All  such  switches  shall  bear  labels  indicating 
their  functions. 

NOTE  —  Such  switchboards  shall  be  located  away 
from  areas  likely  to  be  crowded  by  the  public. 

Open  type  switchboards  wherever  existing  in  old 
buildings  shall  be  phased  out  and  replaced  with 
protected-type  switchboards  with  suitable  circuit 
breakers. 

5.4.2.4  Recessing  of  boards 

Where  so  specified,  the  switchboards  shall  be  recessed 
in  the  wall.  Ample  room  shall  be  provided  at  the  back 
for  connection  and  at  the  front  between  the  switchgear 
mountings  {see  5.3. 6.8). 

5.4.2.5  Marking  of  apparatus  {see  also  good  practices 
[8-2(24)]} 

Where  a  board  is  connected  to  voltage  higher  than 
250  V,  all  the  apparatus  mounted  on  it  shall  be  marked 
with  the  following  colours  to  indicate  the  different  poles 
or  phases  to  which  the  apparatus  or  its  different 
terminals  may  have  been  connected: 

a)  Alternating  current  (three-phase)  system: 
Phase  1  -  red,  Phase  2  -  yellow  and  Phase  3  - 
blue;  and  1  Neutral  -  black 

b)  Direct  current  (three-wire  system ): 

2  outer  wire,  Positive  -  red  and  Negative  - 
blue;  and  1  Mid  wire  (Neutral)  -  black 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


39 


Where  four-wire  three-phase  wiring  is  done,  the  neutral 
shall  be  in  one  colour  and  the  other  three  phase  conductors 
in  another  colour  (preferably  brown)  or  shall  be  suitably 
tagged  or  sleeved  to  ensure  fool  proof  identification. 

NOTE  —  Generally  brown  colour  identification  is  adopted  for 
the  phase  conductors  and  black  for  neutral  with  additional  tags 
or  sleeves  or  coloured  tapes  at  terminations. 

Earth  continuity  conductor  shall  be  marked  with  green 
colour  or  green  with  yellow  line. 

Where  a  board  has  more  than  one  switchgear,  each  such 
switchgear  shall  be  marked  to  indicate  the  section  of 
the  installation  it  controls.  The  main  switchgear  shall 
be  marked  as  such.  Where  there  is  more  than  one  main 
switchboard  in  the  building,  each  such  switchboard 
shall  be  marked  to  indicate  the  section  of  the  installation 
and/or  building  it  controls. 

All  markings  shall  be  clear  and  permanent. 

5.4.2.6  Drawings 

Before  proceeding  with  the  actual  construction,  a  proper 
drawing  showing  the  detailed  dimensions  and  design 
including  the  disposition  of  the  mountings  of  the  boards, 
which  shall  be  symmetrically  and  neatly  arranged  for 
arriving  at  the  overall  dimensions,  shall  be  prepared 
along  the  building  drawing.  Such  drawings  will  show 
the  mandatory  clearance  spaces  if  any,  and  clear  height 
below  the  soffit  of  the  beam  required  to  satisfy 
regulations  and  safety  considerations,  so  that  other 
designers  or  installers  do  not  get  into  such  areas  or 
spaces  for  their  equipment. 

5.4.3  Distribution  Boards 

A  distribution  board  comprises  one  or  more  protective 
devices  against  over  current  and  ensuring  the 
distribution  of  electrical  energy  to  the  circuits. 
Distribution  board  shall  provide  plenty  of  wiring  space, 
to  allow  working  as  well  as  to  allow  keeping  the  extra 
length  of  connecting  cables,  likely  to  be  required  for 
maintenance. 

5.4.3. 1  Main  distribution  board  shall  be  provided  with 
a  circuit  breaker  on  each  pole  of  each  circuit,  or  a  switch 
with  a  fuse  on  the  phase  or  live  conductor  and  a  link  on 
the  neutral  or  earthed  conductor  of  each  circuit.  The 
switches  shall  always  be  linked. 

All  incomers  should  be  provided  with  surge  protection 
devices  depending  upon  the  current  carrying  capacity 
and  fault  level  ( see  11 ).  Surge  protecting  devices  should 
be  provided  with  backup  circuit  breaker/fuses, 
wherever  required. 

5.4.4  Branch  Distribution  Boards 

5. 4. 4.1  Branch  MCB  distribution  boards  shall  be 
provided,  along  with  earth  leakage  protective  device 
(RCCB/RCD)  in  the  incoming,  with  a  fuse  or  a 


miniature  circuit  breaker  or  both  of  adequate  rating/ 
setting  chosen  on  the  live  conductor  of  each  sub-circuit 
and  the  earthed  neutral  conductor  shall  be  connected 
to  a  common  link  and  be  capable  of  being  disconnected 
individually  for  testing  purposes.  At  least  one  spare 
circuit  of  the  same  capacity  shall  be  provided  on  each 
branch  distribution  board.  Further,  the  individual 
branching  circuits  (outgoing)  shall  be  protected  against 
over-current  with  miniature  circuit  breaker  of  adequate 
rating.  In  residential/industrial  lighting  installations,  the 
various  circuits  shall  be  separated  and  each  circuit  shall 
be  individually  protected  so  that  in  the  event  of  fault, 
only  the  particular  circuit  gets  disconnected.  In  order 
to  provide  protection  against  electric  shock  due  to 
leakage  current  for  human  being,  a  30  mA  RCCB/  RCD 
shall  be  installed  at  distribution  board  incomer  of 
buildings,  such  as  residential,  schools  and  hospitals. 
For  all  other  buildings,  a  100  mA  RCCB/RCD  will 
suffice  for  protection  against  leakage  current. 

In  case  of  phase  segregated  distribution  boards,  earth 
leakage  protective  device  shall  be  provided  in  the  sub¬ 
incomer  to  provide  phase  wise  earth  fault  protection. 
The  provision  of  sub-incomer  in  distribution  board  shall 
be  as  per  consumer  requirement. 

5. 4. 4. 2  Common  circuit  shall  be  provided  for 
installations  at  higher  level  (those  in  the  ceiling  and  at 
higher  levels,  above  1  m,  on  the  walls)  and  for 
installations  at  lower  level  but  with  separate  switch 
control  (sockets  for  portable  or  stationery  plug  in 
equipment).  For  devices  consuming  high  power  and 
which  are  to  be  supplied  through  supply  cord  and  plug, 
separate  wiring  shall  be  done.  For  plug-in  equipment 
provisions  shall  be  made  for  providing  RCCB/RCD 
protection  in  the  distribution  board. 

5.4.4.3  It  is  preferable  to  have  additional  circuit  for 
kitchen  and  bathrooms.  Such  sub-circuit  shall  not  have 
more  than  a  total  of  ten  points  of  light,  fans  and  6  A 
socket  outlets.  The  load  of  such  circuit  shall  be 
restricted  to  800  W  and  the  wiring  with  1 .5  mm2  copper 
conductor  cable  is  recommended.  If  a  dedicated  circuit 
is  planned  for  light  fixtures,  the  load  of  such  circuit 
shall  be  restricted  to  400  W  and  the  wiring  with  1.5  mm2 
copper  conductor  cable  is  recommended.  If  a  dedicated 
circuit  is  planned  for  6A  sockets  the  load  of  such  a 
circuit  shall  be  restricted  to  800  W  or  a  maximum  of 
8  numbers,  whichever  is  lesser,  controlling  MCB  should 
be  sized  accordingly.  The  wiring  shall  be  with  1 .5  mm2 
copper  conductor  cable.  If  a  separate  fan  circuit  is 
provided,  the  number  of  fans  in  the  circuit  shall  not 
exceed  ten.  Power  sub-circuit  shall  be  designed 
according  to  the  load  but  in  no  case  shall  there  be  more 
than  two  16  A  outlets  on  each  sub-circuit  which  can  be 
wired  with  4  mm2  for  miscellaneous  socket  loads  and 
shall  be  with  4  mm2  copper  conductor  cable  for 
equipment  consuming  more  than  1  kW.  Power  sockets 


40 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


complying  with  the  accepted  standards  [8-2(25)]  with 
current  rated  according  to  their  starting  load,  wiring, 
MCB,  etc,  shall  be  designed  for  special  equipment 
space  heaters,  air  conditioners,  heat  pumps,  VRF,  etc. 

For  feeding  final  single  phase  domestic  type  of  loads 
or  general  office  loads  it  is  advisable  to  introduce 
additional  cables  if  required  to  allow  lowering  of  short 
circuit  rating  of  the  switchgear  required  at  user  end. 
Use  of  hand  held  equipment  fed  through  flexible  cords 
is  safe. 

5.4.4.4  The  circuits  for  lighting  of  common  area  shall 
be  separate.  For  large  halls  3-wire  control  with 
individual  control  and  master  control  installed  near  the 
entrance  shall  be  provided  for  effective  conservation 
of  energy.  Occupancy  sensors,  movement  sensors,  lux 
level  sensors,  etc,  may  also  be  considered  as  switching 
options  for  lights,  fans,  TV,  etc,  for  different  closed 
spaces  ( see  also  Part  11  ‘Approach  to  Sustainability’ 
of  the  Code). 

5. 4. 4. 5  Where  daylight  is  abundantly  available, 
particularly  in  large  halls,  lighting  in  the  area  near  the 
windows  likely  to  receive  daylight  shall  have  separate 
controls  for  lights,  so  that  they  can  be  switched  off/ 
automatically  reduce  intensity  selectively  when  daylight 
is  adequate,  while  keeping  the  lights  in  the  areas  remote 
from  the  windows  on  ( see  also  Part  1 1  ‘Approach  to 
Sustainability’  of  the  Code). 

5.4.4.6  Circuits  for  socket  outlets  may  be  kept  separate 
from  circuits  feeding  fans  and  lights.  Normally,  fans 
and  lights  may  be  wired  on  a  common  circuit.  In  large 
spaces,  circuits  for  fans  and  lights  may  also  be 
segregated.  Lights  may  have  group  control  in  large  halls 
and  industrial  areas.  While  providing  group  control, 
consideration  may  be  given  for  the  nature  of  use  of  the 
area  lit  by  a  group.  Consideration  has  to  be  given  for 
the  daylight  utilization,  while  grouping,  so  that  a  group 
feeding  areas  near  windows  receiving  daylight  can  be 
selectively  switched  off  during  daylight  period. 

5.4.4. 7  The  load  on  any  low  voltage  sub-circuit  shall 
not  exceed  3  000  W.  In  case  of  a  new  installation,  all 
circuits  and  sub-circuits  shall  be  designed  with  an  initial 
load  of  about  2  500  W,  so  as  to  allow  a  provision  of 
20  percent  increase  in  load  due  to  any  future 
modification.  Power  sub-circuits  shall  be  designed 
according  to  the  load,  where  the  circuit  is  meant  for  a 
specific  equipment.  Good  practice  is  to  limit  a  circuit 
to  a  maximum  of  three  sockets,  where  it  is  expected 
that  there  will  be  diversity  due  to  use  of  very  few  sockets 
in  large  spaces  (example  sockets  for  use  of  vacuum 
cleaner).  General  practice  is  to  limit  it  to  two  sockets 
in  a  circuit,  in  both  residential  and  non-residential 
buildings  and  to  provide  a  single  socket  on  a  circuit 
for  a  known  heavy  load  appliance  such  as  air 
conditioner,  cooking  range,  etc. 


5.4.4. 8  In  wiring  installations  at  special  places  like 
construction  sites,  stadia,  shipyards,  open  yards  in 
industrial  plants,  etc,  where  a  large  number  of  high 
wattage  lamps  may  be  required,  there  shall  be  no 
restriction  of  load  on  any  circuit  but  conductors  used 
in  such  circuits  shall  be  of  adequate  size  for  the  load 
and  proper  circuit  protection  shall  be  provided.  The 
distribution  boards  (DBs)  used  in  these  areas  shall  be 
of  UV  resistant,  double  insulated  type  with  IP  66  or 
higher  degree  of  protection.  Power  tools  and  other 
temporary  equipment  connected  to  these  DBs  shall  be 
sufficiently  protected  against  electrical  faults.  Insulated 
IP  66  sockets  complying  with  the  accepted  standards 
[8-2(25)]  used  in  these  DBs  shall  have  interlocking 
facility  in  addition  to  protection  to  ensure  safe  plugging 
and  unplugging  of  these  equipment. 

5.4.5  Location  of  Distribution  Boards 

a)  The  distribution  boards  shall  be  located  as 
near  as  possible  to  the  centre  of  the  load  they 
are  intended  to  control. 

b)  These  shall  be  fixed  on  suitable  stanchion  or 
wall  and  shall  be  accessible  for  replacement/ 
reset  of  protective  devices,  and  shall  not  be 
more  than  1.8  m  from  floor  level. 

c)  These  shall  be  of  either  metal-clad  type,  or 
polycarbonate  enclosure  of  minimum  IP  42. 
But,  if  exposed  to  weather  or  damp  situations, 
these  shall  be  of  the  weatherproof  type 
conforming  to  IP  55  and,  if  installed  where 
exposed  to  explosive  dust,  vapour  or  gas,  these 
shall  be  of  flameproof  type  in  accordance  with 
accepted  standards  [8-2(26)].  In  corrosive 
atmospheres,  these  shall  be  treated  with  anti¬ 
corrosive  preservative  or  covered  with  suitable 
plastic  compound. 

d)  Where  two  and/or  more  distribution  boards 
feeding  low  voltage  circuits  are  fed  from  a 
supply  of  medium  voltage,  the  metal  case  shall 
be  marked  ‘Danger  415  Volts’  and  identified 
with  proper  phase  marking  and  danger  marks. 

e)  Each  shall  be  provided  with  a  circuit  list  giving 
diagram  of  each  circuit  which  it  controls  and 
the  current  rating  of  the  circuit  and  size  of  fuse 
element. 

f)  In  wiring  branch  distribution  board,  total  load 
of  consuming  devices  shall  be  divided  as  far 
as  possible  evenly  between  the  number  of 
ways  in  the  board  leaving  spare  circuits  for 
future  extension. 

g)  Distribution  board  shall  not  be  located  at 
structural  expansion  joints  of  the  building. 

h)  Distribution  board/other  electrical  outlets  shall 
have  a  minimum  calculated  separation 
distance  from  lightning  protection  down- 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


41 


conductors  to  avoid  flash  over  in  case  of 
lightning. 

j)  Walls  with  flushed  distribution  boards  shall 
have  adequate  support  behind  and  surrounding 
so  that  there  is  no  physical  weight  on  the 
distribution  board  of  the  civil  structure  around. 
Electrical  switch  sockets,  etc,  shall  also  be 
avoided  to  be  mounted  behind  the  distribution 
board  to  avoid  touching  the  board  from 
behind. 

5.4.6  Protection  of  Circuits 

a)  Appropriate  protection  shall  be  provided  at 
switchboards,  distribution  boards  and  at  all 
levels  of  panels  for  all  circuits  and  sub-circuits 
against  short  circuit,  over-current  and  other 
parameters  as  required.  The  protective  device 
shall  be  capable  of  interrupting  maximum 
prospective  short  circuit  current  that  may 
occur,  without  danger.  The  ratings  and  settings 
of  fuses  and  the  protective  devices  shall  be 
coordinated  so  as  to  afford  selectivity  in 
operation  and  in  accordance  with  accepted 
standards  [8-2(27)]. 

b)  Where  circuit-breakers  are  used  for  protection 
of  a  main  circuit  and  of  the  sub-circuits 
derived  therefrom,  discrimination  in  operation 
may  be  achieved  by  adjusting  the  protective 
devices  of  the  sub-main  circuit-breakers  to 
operate  at  lower  current  settings  and  shorter 
time-lag  than  the  main  circuit-breaker. 

c)  Where  HRC  type  fuses  are  used  for  back-up 
protection  of  circuit-  breakers,  or  where  HRC 
fuses  are  used  for  protection  of  main  circuits, 
and  circuit-breakers  for  the  protection  of  sub¬ 
circuits  derived  there  from,  in  the  event  of 
short-circuits  protection  exceeding  the  short- 
circuits  protection  exceeding  the  short-circuits 
capacity  of  the  circuit-breakers,  the  HRC  fuses 
shall  operate  earlier  than  the  circuit-breakers; 
but  for  smaller  overloads  within  the  short- 
circuit  capacity  of  the  circuit-breakers,  the 
circuit-breakers  shall  operate  earlier  than  the 
HRC  fuse  blows. 

d)  If  rewireable  type  fuses  are  used  to  protect 
sub-circuits  derived  from  a  main  circuit 
protected  by  HRC  type  fuses,  the  main  circuit 
fuse  shall  normally  blow  in  the  event  of  a 
short-circuit  or  earth  fault  occurring  on  sub¬ 
circuit,  although  discrimination  may  be 
achieved  in  respect  of  overload  currents.  The 
use  of  rewireable  fuses  is  restricted  to  the 
circuits  with  short-circuit  level  of  4  kA;  for 
higher  level  either  cartridge  or  HRC  fuses 
shall  be  used.  However,  use  of  rewireable  fuse 
is  not  desirable,  even  for  lower  fault  level 
areas.  MCB’s  provide  a  better  and  dependable 


protection,  as  their  current  setting  is  not 
temperable. 

e)  A  fuse  carrier  shall  not  be  fitted  with  a  fuse 
element  larger  than  that  for  which  the  carrier 
is  designed. 

f)  The  current  rating  of  a  fuse  or  circuit  breaker 
shall  not  exceed  the  current  rating  of  the 
smallest  cable  in  the  circuit  protected  by  the 
fuse. 

g)  Every  fuse  shall  have  its  own  case  or  cover 
for  the  protection  of  the  circuit  and  an  indelible 
indication  of  its  appropriate  current  rating  in 
an  adjacent  conspicuous  position. 

h)  All  distribution  board  or  panel  incomer  may 
be  protected  by  a  surge  protection  device,  if 
found  necessary  ( see  11).  Separate  HRC  fuse/ 
CB  with  proper  enclosure  may  be  required  in 
series  with  the  surge  protection  device  with 
main  incomer.  Back-up  fuse/CB  shall  be  of 
the  capacity  not  lower  than  that  recommended 
by  the  SPD  manufacturer.  Short  circuit 
withstand  capability  of  the  SPDs  should  be 
coordinated  with  the  HRC  fuse/CB  and  SPD 
should  be  selected  to  be  matching  the  fault 
power  expected/calculated  at  that  point. 

5.4.7  Cascading,  Discrimination  and  Limitation 

Cascading  and  discrimination  in  switchgear 
downstream  and  upstream  shall  be  designed  and 
maintained  such  that  the  continuity  of  power  in  case  of 
any  abnormal  conditions  such  as  overload,  short  circuit 
and  earth  faults,  etc  is  maintained  and  only  faulty  circuit 
is  isolated  and  power  is  made  available  to  other  loads. 

Cascading  technique  allows  the  designer  to  select 
circuit  breakers  of  lower  breaking  capacities.  Utilizing 
the  current  limiting  effect  of  the  incoming  breaker, 
outgoing  breaker  can  sustain  the  higher  faults  than  its 
capacity  and  even  maintain  the  discrimination. 

5.5  Protection  Class  of  Equipment  and  Accessories 

The  class  of  ingress  protection  (IP)  and  protection 
against  mechanical  impact  (IK)  {see  also  good  practice 
[8-2(6)]  and  IEC  62262:2002  ‘Degrees  of  protection 
provided  by  enclosures  for  electrical  equipment  against 
external  mechanical  impacts  (IK  code)’}  shall  be 
specific  depending  on  the  requirement  at  the  place  of 
installation. 

5.6  Voltage  and  Frequency  of  Supply 

It  should  be  ensured  that  all  equipment  connected  to 
the  system  including  any  appliances  to  be  used  on  it 
are  suitable  for  the  voltage  and  frequency  of  supply  of 
the  system.  The  nominal  values  of  low  and  medium 
voltage  systems  in  India  are  240  V  and  415  V  a.c., 
respectively,  and  the  frequency  is  50  Hz. 


42 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


NOTE  —  The  design  of  the  wiring  system  and  the  sizes  of  the 
cables  should  be  decided  taking  into  account  following  factors: 

a)  Voltage  drop  —  This  should  be  kept  below 
6  percent  to  ensure  proper  functioning  of  all 
electrical  appliances  and  equipment  including 
motors; 

b)  Thermal  limit  based  current  carrying  capacity 
of  the  cable  with  appropriate  derating  factors 
applicable  to  the  installation  conditions; 

c)  Capacity  to  withstand  the  let  through  fault 
current  based  on  the  fault  level  and  the 
controlling  switchgear  disconnection 
characteristics. 

5.7  Rating  of  Cables  and  Equipment 

5.7.1  The  current-carrying  capacity  of  different  types 
of  cables  shall  be  chosen  in  accordance  with  good 
practice  [8-2(28], 

5.7.2  The  current  ratings  of  switches  for  domestic  and 
similar  purposes  are  6  A,  16  A,  20  A  and  25  A. 

5.7.3  The  current  ratings  of  isolators  and  normal  duty 
switches  and  composite  units  of  switches  and  fuses  shall 
be  selected  from  one  of  the  following  values: 

16,  25,  32,  63,  100,  160,  200,  320,  400,  500,  630, 
800,  1  000  and  1  250  A. 


5.7.4  The  ratings  ofrewireable  and  HRC  fuses  shall  be 
in  accordance  with  good  practice  [8-2(29)]. 

5.7.5  The  current  ratings  of  miniature  circuit-breakers 
shall  be  chosen  from  the  values  given  below: 

6,  10,  16,  20,  25,  32,  40,  50,  63,  80,  100  and  125  A. 

5.7.6  The  current  ratings  of  moulded  case  circuit 
breakers  shall  be  chosen  from  the  values  given  below: 

100, 125, 160,  200,  250,  315, 400,  630,  800, 1  000, 
1  250  and  1  600A. 

5.7.7  The  current  ratings  of  air  circuit-breakers  shall 
be  chosen  from  the  values  given  below: 

630,  800,  1  000,  1  250,  1  600,  2  000,  2  500,  3  200, 
4  000A  and  6  300  A. 

5.7.8  The  current  ratings  of  the  distribution  fuse  board 
shall  be  selected  from  one  of  the  following  values: 

6,  16,  25,  32,  63  and  100  A. 

5.8  Installation  Circuits 

5.8.1  The  nominal  cross-sectional  area  of  copper  phase 
conductors  in  a.c.  circuits  and  of  live  conductors  in 
d.c.  circuits  shall  be  not  less  than  the  values  specified 
below: 


SI 

No. 

(1) 

Type  of  Circuit 

(2) 

Minimum 
Copper  Wire 
Size 

(3) 

Number  of  Circuits 

(4) 

i) 

Lighting 

1.5  mm2 

2  or  more 

ii) 

Socket-outlets,  6  A 

2.5  mm2 

Any  number 

Areas  such  as  kitchens  and  laundries  3  x  double 
socket-outlets  per  circuit.  Other  areas  up  to  12 
double  socket-outlets 

iii) 

Signaling  and  control  circuits 

0.5  mm2 
(see  Note  1) 

— 

iv) 

Socket-outlets,  16  A 

2.5  mm2 

1 

v) 

Water  heater  <  3  kW 

2.5  mm2 

1 

vi) 

Heaters  or  electric  equipment 
more  than  or  equal  to  3  kW 

4.0  mm2 

1 

vii) 

Free  standing  electric  range 
Separate  oven  and/or  cook  top 

4.0  mm2 

1 

viii) 

Air  conditioner  >  1.5  t 

4.0  mm2 

1 

ix) 

Permanently  connected 
appliances  including 
dishwashers,  heaters,  etc 

2.5  mm2 

1  above  10  A.  Up  to  10  A  can  be  wired  as  part 
of  a  socket-outlet  circuit 

x) 

Appliance  rated  >3  kW<6  kW 

6.0  mm2 

— 

XI) 

Submains  to  garage  or  out¬ 
building 

2.5  mm2 

1  for  each 

xii) 

Mains  cable 

It  should  be  based  on  demand  load/peaking 
loads  and  future  loading. 

NOTE  —  In  multi -core  flexible  cables  containing  7  or  more  cores  and  in 
a  minimum  nominal  cross  -sectional  area  of  0. 1  mm 2  is  permitted. 

signalling  control  circuits  intended  for  electronic  equipment 

PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


43 


5.8.2  Aluminum  conductor  cables  in  sizes  less  than 
16  mm2  cause  termination  problems  leading  to  heating 
at  the  terminals  and  enhance  the  possibility  of  a  fire.  For 
conductor  sizes  less  than  or  equal  to  1 6  mm2,  only  copper 
conductor  cables  should  be  used. 

5.8.3  Switch  or  isolator  controlling  a  water  heater  or 
geyser  should  not  be  located  within  1  m  from  the 
location  of  a  shower  or  bath  tub,  to  avoid  a  person  in 
wet  condition  reaching  the  switch  or  isolator.  It  is 
preferable  to  provide  the  control  switch  outside  the  bath 
room  near  the  entrance  and  provide  an  indication  at 
the  water  heater.  A  socket  or  a  connector  block  with 
suitable  protection  against  water  spray  should  be 
provided  to  connect  the  water  heater.  The  above 
considerations  apply  to  switches  for  outdoor  lights  and 
other  appliances,  with  the  objective  of  avoidance  of 
operation  of  a  switch  when  a  person  is  wet. 

5.8.4  Sockets  in  kitchen,  bathroom,  toilet,  garage,  etc, 
should  not  be  provided  within  a  height  of  1  m  from  the 
ground  level.  Similar  care  has  to  be  taken  for  installations 


involving  fountains,  swimming  pools,  etc.  Light  fittings 
in  such  areas  should  be  fed  at  low  voltage,  preferably 
through  an  isolating  transformer  with  a  proper  earth 
leakage  protection.  Where  possibility  of  a  person  in 
contact  with  a  wet  surface  has  to  operate  or  touch  an 
electrical  switch  or  an  appliance  the  circuit  should  be 
protected  by  a  100/30  mA  RCCB/RCD,  as  applicable. 

5.8.5  Selecting  and  Installing  Cables 

5.8.5. 1  Cable  insulation  types 

For  the  purpose  of  this  Code,  cables  above  1  mm2  shall 
have  stranded  conductors.  All  cables  when  installed,  shall 
be  adequately  protected  against  mechanical  damage.  This 
can  be  carried  out  by  either  having  additional  protection, 
such  as  being  enclosed  in  PVC  conduit  or  metal  pipes, 
or  placing  the  cables  in  a  suitable  location  that  requires 
no  additional  protection.  The  cables  for  wiring  circuits 
in  electrical  installation  shall  have  the  appropriate  wire 
size  matching  the  requirement  of  the  loads  and  the 
following  table  gives  the  recommendations  for  different 
types  of  loads: 


For  the  mains  cable 

For  installation  wiring 

For  main  earth  or  main  equipotential  wire 

Underground  installation  and  installation  in  cable 
feeders  between  buildings,  etc 


Tough  plastic  sheathed  (TPS)  cable 
Tough  plastic  sheathed  (TPS)  cables 

Poly  vinyl  chloride  (PVC)  insulated  conduit 
wire 

trench,  PVC  insulated,  PVC  sheathed  armored 
cables  or  XLPE  insulated,  PVC  sheathed 
cables  armoured  cables 


Installation  in  plant  rooms,  switch  rooms  etc,  on  cable  tray  PVC  insulated,  PVC  sheathed  or  XLPE 
or  ladder  or  protected  trench,  where  risk  of  mechanical  insulated,  PVC  sheathed  unarmoured  cables 

damage  to  cable  does  not  exist. 


5.8.5.2  Circuit  wire  sizes 


Recommended  minimum  wire  sizes  for  various  circuits  is  given  below: 


SI 

No. 

Circuits 

Minimum  Wire  Size 

Wire  Colour 

(1) 

(2) 

(3) 

(4) 

i) 

1-way  lighting 

2  +  E  cable  wires 

1.5  mm2 

Red-Black-Green  or 

Green/Y  ellow 

ii) 

2-way  lighting  control  (straps 
between  the  2  switches) 

3  wire  cable 

1.5  mm2 

Red- White-Blue 

hi) 

Storage  water  heaters  up  to  3  kW 

2  +  E  cable 

2.5  mm2  (stranded  conductors) 

Red-Black-Green  or 

Green/Y  ellow 

iv) 

Storage  water  heaters  between 

3  kW  and  6  kW 

2  +  E  cable 

4  mm2  (stranded  conductors) 

Red-Black-Green  or 

Green/Y  ellow 

v) 

Socket-outlets  and  permanent 
connection  units 

2  +  E  cable 

2.5  mm2  (stranded  conductors) 

Red-Black-Green  or 

Green/Y  ellow 

VI) 

Submains  to  garages  or  out 
buildings 

2  +  E  cable 

2.5  mm2  (stranded  conductors) 

Red-Black-Green  or 

Green/Y  ellow 

44 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Circuits 


SI 

No. 


Minimum  Wire  Size 


Wire  Colour 


(1)  (2) 


(3) 


(4) 


vii)  Cooking  hobs 

viii)  Separate  ovens 

ix)  Electric  range 

x)  Mains 

xi)  Main  equipotential  bonding  wire 

xii)  Main  earth  wire 


2  +  E  cable 
1.5  mm2 
2  +  E  cable 

4  mm2  (stranded  conductors) 
2  +  E  cable 

6  mm2  (stranded  conductors) 

2  wire  cable 

16  min2  (stranded  conductors) 
Conduit  wire 

4  mm2  (stranded  conductors) 
Conduit  wire 

6  mm2  (stranded  conductors) 


Red-Black-Green  or 
Green/Yellow 


Red-Black-  Green  or 
Green/Yellow 

Red-Black 

Green  or  Green/Y ellow 
Green  or  Green/Y  ellow 


NOTES 

1  2  +  E  is  also  known  as  twin  and  earth. 

2  Earth  wire  can  be  as  per  the  following: 

a)  Green/Yellow  throughout  their  length  with,  in  addition,  light  blue  markings  at  the  terminations,  or 

b)  Light  blue  throughout  their  length  with,  in  addition,  green/yellow  markings  at  the  terminations. 

3  The  above  sizes  are  recommendatory  and  shall  be  modified  as  per  voltage  drop,  starting  current,  distance  from  DB,  etc. 


5.8.6  Requirements  for  Physical  Protection  of 
Underground  Cables 


SI 

No. 

Protective 

Element 

Specifications 

(1) 

(2) 

(3) 

i) 

Bricks 

(a)  100  mm  minimum 
width 

(b)  25  mm  thick 

(c)  sand  cushioning  100 
mm  and  sand  cover 
100  mm 

ii) 

Concrete  slabs 

At  least  50  mm  thick 

hi) 

Plastic  slabs 

(polymeric 
cover  strips) 

Fibre  reinforced 
plastic 

At  least  1 0  mm  thick, 
depending  on  properties 
and  has  to  be  matched 
with  the  protective 
cushioning  and  cover 

iv) 

PVC  conduit  or 
PVC  pipe  or 
stoneware  pipe 
or  hume  pipe 

The  pipe  diameter 
should  be  such  so  that 
the  cable  is  able  to 
easily  slip  down  the  pipe 

v) 

Galvanized  pipe 

The  pipe  diameter 
should  be  such  so  that 
the  cable  is  able  to 
easily  slip  down  the  pipe 

The  trench  shall  be  backfilled  to  cover  the  cable  initially 
by  200  mm  of  sand  fill;  and  then  a  plastic  marker  strip 
shall  be  put  over  the  full  length  of  cable  in  the  trench. 
The  marker  signs  shall  be  provided  where  any  cable 
enters  or  leaves  a  building.  This  will  identify  that  there 
is  a  cable  located  underground  near  the  building.  The 
trench  shall  then  be  completely  filled.  If  the  cables  rise 
above  ground  to  enter  a  building  or  other  structure,  a 
mechanical  protection  such  as  a  GI  pipe  or  PVC  pipe 
for  the  cable  from  the  trench  depth  to  a  height  of  2.0  m 
above  ground  shall  be  provided. 

5.9  Lighting  and  Levels  of  Illumination 

5.9.1  General 

Lighting  installation  shall  take  into  consideration  many 
factors  on  which  the  quality  and  quantity  of  artificial 
lighting  depends.  Recent  practice  in  illumination  is  to 
provide  the  required  illumination  with  a  large  number 
of  light  sources  (not  of  higher  illumination  level)  instead 
of  fewer  number  of  light  sources  of  higher  illumination 
level,  to  produce  higher  unifonnity  in  illumination  level. 

Now  a  wide  variety  of  light  sources,  such  as,  fluorescent 
lamps  [tubular  (TL)  and  compact  (CFL)],  light  emitting 
diodes  (LED)  and  induction  lighting  are  available  in 
addition  to  the  incandescent  lamps  (GLS  and  halogen), 
for  application  in  buildings.  Most  of  them  are 
competitive  when  applied  in  the  segment  for  which  a 
particular  type  is  well  suited. 

With  the  increase  in  energy  costs  and  awareness  of  the 
need  to  conserve  energy  for  the  protection  of  the 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


45 


environment,  lighting  design  is  becoming  complex. 
With  the  developments  in  the  types  of  light  sources 
and  their  control  systems  now  available,  lighting  design 
goes  with  the  concept  of  better  light  with  less  energy 
and  least  impact  on  environment. 

Automatic  lighting  control  schemes  may  be  considered 
to  have  efficient  utilization  of  lights.  Automatic  controls 
can  take  care  of  the  switching  off  when  the  space  served 
has  no  activity  or  is  illuminated  by  daylight. 

5.9.2  Electrical  Installations  for  Lighting 

The  concepts  or  needs  of  energy  conservation  today 
require  more  lights  to  be  provided  so  that  different  sets  of 
lights  are  used  to  light  up  the  area  of  activity  to  the  required 
higher  level  of  lighting  needed  for  the  activity  and  provide 
a  general  minimum  background  level  of  lighting.  Any 
space  requires  two  or  three  different  combination  of 
lighting  sets  associated  with  the  activity  and  this  may 
require  the  wiring  to  be  provided  to  accommodate  the 
lighting  groups  in  different  circuits  with  group  controls, 
automatic  controls  and  remote  controls. 

Availability  of  LED  lights  with  a  wide  range  from  1  W 
to  100  W  allows  designers  to  provide  spot  task  lighting 
of  a  high  illumination  level  combined  with  a  general 
space  lighting  of  low  illumination.  As  light  follows  the 
inverse  square  law,  provision  of  the  light  source  close 
to  the  task  reduces  the  energy  need. 

Lighting  demand  for  buildings  should  be  considered 
as  per  type  of  building.  Where  nothing  is  specified,  for 
lighting  demand  of  any  type  of  building  a  maximum  of 
13  W/m2  of  all  built-up  areas  including  balconies. 
Covered  parking  areas  may  be  considered  at  3.23  W/m2 
including  balconies,  service  areas,  corridors,  etc,  may 
be  considered  with  very  basic  diversity  of  80  percent 
to  100  percent.  Power  requirements  shall  be  considered 
at  least  55  W/m2  with  an  overall  diversity  not  exceeding 
50  percent.  These  shall  be  excluding  defined  loads  such 
as  lifts,  plumbing  system,  fire  fighting  systems, 
ventilation  requirement,  etc. 

While  incandescent  lamps  (GLS  or  halogen)  does  not 
require  any  control  gear,  other  light  sources  such  as 
tubular  fluorescent  lamps,  compact  fluorescent  lamps, 
mercury  vapour  lamps,  sodium  vapour  lamps,  metal 
halide  lamps  and  light  emitting  diode  (LED)  lamps  have 
non-linear  characteristics  and  require  specifically  made 
control  gear  for  each  type  of  lamp  for  their  proper 
operation.  In  some  cases  the  control  gear  is  integral 
with  the  lamp  and  in  some  it  is  with  light  fitting  and  in 
some  it  is  external.  The  electrical  installation  and  wiring 
has  to  take  this  into  account  and  provide  appropriate 
space  for  such  control  gear.  There  will  be  heat  emission, 
introduction  of  harmonics  etc,  and  they  also  consume 
some  energy.  The  electrical  and  lighting  system  design 
has  to  keep  this  aspect  in  the  wiring  design  and 


installation.  Control  gear  contributes  or  influences 
energy  conservation  significantly  and  due  care  should 
be  taken  to  ensure  a  proper  choice. 

5.9.3  Principles  of  Lighting 

When  considering  the  function  of  artificial  lighting, 
attention  shall  be  given  to  the  following  principle 
characteristics  before  designing  an  installation: 

a)  Illumination  and  its  uniformity; 

b)  Special  distribution  of  light.  This  includes  a 
reference  to  the  composition  of  diffused  and 
directional  light,  direction  of  incidence,  the 
distribution  of  luminances  and  the  degree  of 
glare; 

c)  Colour  of  the  light  and  colour  rendition; 

d)  Natural  light  sources,  if  possible  such  as  light 
tubes;  and 

e)  System  wattage  of  the  luminaire  proposed. 

5.9.4  The  variety  of  purposes  which  have  to  be  kept  in 
mind  while  planning  the  lighting  installation  may  be 
broadly  grouped  as: 

a)  Industrial  buildings  and  processes; 

b)  Offices,  schools  and  public  buildings; 

c)  Surgeries  and  hospitals;  and 

d)  Hostels,  restaurants,  shops  and  residential 
buildings. 

5.9.4. 1  It  is  important  that  appropriate  levels  of 
illumination  for  these  and  the  types  and  positions  of 
fittings  determined  to  suit  the  task  and  the  disposition 
of  the  working  planes. 

5.9.5  For  detailed  requirements  for  lighting  and  lighting 
design  and  installations,  reference  shall  be  made  to 
National  Lighting  Code.  For  specific  requirements  for 
lighting  of  special  occupancies,  reference  shall  be  made 
to  good  practice  [8-2(30)]  and  the  National  Lighting 
Code. 

5.9.6  Energy  Conservation 

Energy  conservation  may  be  achieved  by  using  the 
following: 

a)  Energy  efficient  lamps,  chokes,  ballast,  etc, 
for  lighting  equipment. 

b)  Efficient  switching  systems  such  as  remote 
sensors,  infrared  switches,  master  switches, 
occupancy  sensors,  light  sensors,  light 
automation,  remote  switches,  etc  for  switching 
‘ON’  and  ‘OFF’  of  lighting  circuits. 

c)  Properly  made/connected  joints/contacts  to 
avoid  loose  joints  leading  to  loss  of  power. 

5.10  In  locations  where  the  system  voltage  exceeds 
650  V,  as  in  the  case  of  industrial  locations,  for  details 
of  design  and  construction  of  wiring  installation, 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


reference  may  be  made  to  good  practice  [8-2(11)]. 

5.11  Guideline  for  Electrical  Layout  in  Residential 
Buildings 

For  guidelines  for  electrical  installation  in  residential 
buildings,  reference  may  be  made  to  good  practice 
[8-2(31)]. 

A  typical  distribution  scheme  in  a  residential  building 
with  separate  circuits  for  lights  and  fans  and  for  power 
appliances  is  given  in  Fig.  3. 

5.12  For  detailed  information  regarding  the  installation 
of  different  electrical  equipment,  reference  may  be 
made  to  good  practice  [8-2(32)]. 

6  WIRING 

6.1  Provision  for  Maximum  Load 

All  conductors,  switches  and  accessories  shall  be  of 
such  size  as  to  be  capable  of  carrying,  without  their 
respective  ratings  being  exceeded,  the  maximum 
current  which  will  normally  flow  through  them. 

6.1.1  Estimation  of  Load  Requirements 


In  estimating  the  current  to  be  carried  by  any  conductor 
the  following  ratings  shall  be  taken,  unless  the  actual 
values  are  known  or  specified  for  these  elements: 


SI 

Element 

Rating 

No. 

W 

(1) 

(2) 

(3) 

i) 

Incandescent  lamp 

60 

ii) 

Ceiling  fan 

60 

in) 

Table  fan 

60 

iv) 

6  A  socket  outlet 

100,  unless  the 
actual  value  of 
loads  are  specified 

v) 

1 6  A  socket  outlet 

1  000,  unless  the 
actual  value  of 
loads  are  specified 

vi) 

Fluorescent  light: 
Length  : 
a)  600  mm 

25 

b)  1  200  mm 

50 

c)  1  500  mm 

90 

vii) 

Fligh  pressure 

According  to  their 

mercury  vapour 

capacity,  control 

(HPMV)  lamps,  high 

gear  losses  shall  be 

pressure  sodium 

also  considered  as 

vapour  (F1PSV) 
lamps 

applicable 

viii) 

Compact  fluorescent 
lamp  (CFL) 

20 

ix) 

Light  emitting  diode 
(LED) 

10 

SI 

No. 

(1) 

Element 

(2) 

Rating 

W 

(3) 

x) 

Exhaust  fan 

50 

xi) 

Geyser  (storage  type) 

2  000 

xii) 

Geyser  (instant) 

3  000 

xiii) 

Computer  point 

150 

xiv) 

Computer  (laptop) 

50 

xv) 

Printer,  laser 

1  500 

xvi) 

Printer,  inkjet 

70 

xvii) 

Kitchen  outlet 

1  500 

xviii) 

Air  conditioner: 

1  TR 

1  250 

1.5  TR 

1  875 

2  TR 

2  500 

2.5  TR 

3  200 

6.1.2  Electrical  installation  in  a  new  building  shall 
normally  begin  immediately  on  the  commencement  of 
the  main  structural  building  work  and  before  finishing 
work  such  as  plastering  has  begun  except  in  the  case  of 
surface  wiring  which  can  be  carried  out  after  the  plaster 
work.  Usually,  no  installation  work  should  start  until 
the  building  is  reasonably  weatherproof,  but  where 
electric  wiring  is  to  be  concealed  within  the  structures 
as  may  be  the  case  with  a  reinforced  concrete  building, 
the  necessary  conduits  and  ducts  shall  be  positioned 
firmly  by  tying  the  conduit  to  the  reinforcement  before 
concreting.  Care  should  be  taken  to  avoid  use  of 
damaged  conduit  or  ducts,  the  conduits  end  shall  be 
given  suitable  anti-corrosive  treatment  and  holes 
blocked  off  by  putties  or  caps  to  protect  conduits  from 
getting  blocked.  All  conduit  openings  and  junction  box 
openings,  etc  shall  be  properly  protected  against  entry 
of  mortar,  concrete,  etc,  during  construction. 

6.2  Selection  of  Size  of  Conductors 

The  size  of  conductors  of  circuits  shall  be  so  selected 
that  the  drop  in  voltage  from  consumer’s  terminals  in  a 
public  supply  (or  from  the  bus-bars  of  the  main 
switchboard  controlling  the  various  circuits  in  a  private 
generation  plant)  to  any  point  on  the  installation  does 
not  exceed  three  percent  of  the  voltage  at  the  consumer’s 
terminals  (or  at  two  bus-bars  as  these  may  be)  when  the 
conductors  are  carrying  the  maximum  current  under  the 
nonnal  conditions  of  service.  The  overall  voltage  drop 
from  the  transformer  end  to  consumer’s  final  distribution 
board  shall  not  exceed  six  percent. 

6.2.1  If  the  cable  size  is  increased  to  reduce  voltage 
drop  in  the  circuit,  the  rating  of  the  cable  shall  be 
sufficient  to  carry  the  current  which  the  circuit  is 
designed  for.  In  each  circuit  or  sub-circuit  the  fuse/ 
circuit-breaker  shall  be  selected  to  match  the  current 
rating  of  the  circuit  to  ensure  the  desired  protection. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


47 


6A  SWITCH 


Fig.  3  Wiring  Diagram  for  a  Typical  Distribution  Scheme  in  a  Residential  Building  Flat 


48 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


6.3  Branch  Switches 

Where  the  supply  is  derived  from  a  three-wire  or  four- 
wire  source,  and  distribution  is  done  on  the  two-wire 
system,  all  branch  switches  shall  be  placed  in  the  outer 
or  live  conductor  of  the  circuit  and  no  single  phase 
switch  or  protective  device  shall  be  inserted  in  the 
middle  wire,  earth  or  earthed  neutral  conductor  of  the 
circuit.  Single-pole  switches  (other  than  for  multiple 
control)  carrying  not  more  than  16  A  may  be  of  tumbler 
type  or  flush  type  which  shall  be  on  when  the  handle  or 
knob  is  down. 

6.4  Layout  and  Installation  Drawing 

6.4.1  The  electrical  layout  should  be  drawn  indicating 
properly  the  locations  of  all  outlets,  such  as,  lamps, 
fans,  appliances  (both  fixed  and  movable)  and  motors 
and  best  suit  for  wiring. 

6.4.2  All  runs  of  wiring  and  the  exact  positions  of  all 
points  of  switch-boxes  and  other  outlets  shall  be  first 
marked  on  the  plans  of  the  building  and  approved  by 
the  Engineer-in-Charge  or  the  owner  before  actual 
commencement  of  the  work. 

6.4.3  Industrial  layout  drawings  should  indicate  the 
relative  civil  and  mechanical  details. 

6.4.4  Layout  of  Wiring 

The  layout  of  wiring  should  be  designed  keeping  in 
view  disposition  of  the  lighting  system  to  meet  the 
illumination  levels.  All  wirings  shall  be  done  on  the 
distribution  system  with  main  and  branch  distribution 
boards  at  convenient  physical  and  electrical  load 
centres.  All  types  of  wiring,  whether  concealed  or 
unconcealed  should  be  as  near  the  ceiling  as  possible. 
In  all  types  of  wirings  due  consideration  shall  be  given 
for  neatness  and  good  appearance. 

6.4.5  Balancing  of  circuits  in  three-wire  or  poly-phase 
installation  shall  be  arranged  beforehand.  Proper 
balancing  can  be  done  only  under  actual  load 
conditions.  Conductors  shall  be  so  enclosed  in  earthed 
metal  or  incombustible  insulating  material  that  it  is  not 
possible  to  have  ready  access  to  them.  Means  of  access 
shall  be  marked  to  indicate  the  voltage  present. 

Where  terminals  or  other  fixed  live  parts  between  which 
a  voltage  exceeding  250  V  exists  are  housed  in  separate 
enclosures  or  items  of  apparatus  which,  although 
separated  are  within  reach  of  each  other,  a  notice  shall 
be  placed  in  such  a  position  that  anyone  gaining  access 
to  live  parts  is  warned  of  the  magnitude  of  the  voltage 
that  exists  between  them. 

Where  loads  are  single  phase,  balancing  should  be  for 
the  peak  load  condition  based  on  equipment  usage. 
Facility  for  change  should  be  built  into  the  distribution 
design. 


NOTE  —  The  above  requirements  apply  equally  to  three-phase 
circuits  in  which  the  voltage  between  lines  or  to  earth  exceeds 
250  V  and  to  groups  of  two  or  more  single-phase  circuits, 
between  which  medium  voltage  may  be  present,  derived 
therefrom.  They  apply  also  to  3 -wire  d.c.  or  3 -wire  single-phase 
a.c.  circuits  in  which  the  voltage  between  lines  or  to  earth 
exceeds  250  V  and  to  groups  of  2-wire  circuits,  between  which 
medium  voltage  may  be  present,  derived  there  from. 

6.4.6  Medium  voltage  wiring  and  associated  apparatus 
shall  comply,  in  all  respects,  with  the  requirements  of 
Regulation  35,  36,  37,  40,  41  and  42  of  Central 
Electricity  Authority  (Measures  Relating  to  Safety’  and 
Electricity  Supply)  Regulations,  2010,  as  amended  from 
time-to-time  ( see  Annex  B). 

6.5  Conductors  and  Accessories 

6.5.1  Conductors 

Conductors  for  all  the  internal  wiring  shall  be  of  copper. 
Conductors  for  power  and  lighting  circuits  shall  be  of 
adequate  size  to  carry  the  designed  circuit  load  without 
exceeding  the  permissible  thermal  limits  for  the 
insulation.  For  final  section  wiring  to  larger  loads,  the 
current  carrying  capacity  will  preside.  The  conductor 
size  shall  also  be  based  on  the  voltage  drop  in  the  line  so 
as  to  provide  a  terminal  voltage  not  below  the  prescribed 
voltage  requirement. 

The  conductor  for  final  sub-circuit  for  fan  and  light  wiring 
shall  have  a  nominal  cross-sectional  area  not  less  than 
1.50  mm2  copper.  The  cross-sectional  area  of  conductor 
for  power  wiring  shall  be  not  less  than  2.5  mm2  copper. 
The  minimum  cross-sectional  area  of  conductor  of 
flexible  cord  shall  be  1.50  mm2  copper. 

In  existing  buildings  where  aluminum  wiring  has  been 
used  for  internal  electrification,  changeover  from 
aluminum  conductor  cables  to  copper  conductor  cables 
is  recommended  as  it  has  been  found  that  aluminum 
conductors  below  1 0  mm2  size  pose  a  number  of  hazards. 

NOTE  —  It  is  advisable  to  replace  wiring,  which  is  more  than 
30  years  old  as  the  insulation  also  would  have  deteriorated, 
and  will  be  in  a  state  to  cause  failure  on  the  slightest  of 
mechanical  or  electrical  disturbance. 

6.5.2  Flexible  Cables  and  Flexible  Cords 

Flexible  cables  and  cords  shall  be  of  copper  and 
stranded  and  protected  by  flexible  conduits  or  tough 
rubber  or  PVC  sheath  to  prevent  mechanical  damage. 

6.5.3  Cable  Ends 

When  a  stranded  conductor  having  a  nominal  sectional 
area  less  than  6  mm2  is  not  provided  with  cable  sockets, 
all  strands  at  the  exposed  ends  of  the  cable  shall  be 
soldered  together  or  crimped  using  suitable  sleeve  or 
ferrules. 

6.5.4  Special  Risk 

Special  forms  of  construction,  such  as  flameproof 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


49 


enclosures,  shall  be  adopted  where  there  is  risk  of  fire 
or  explosion. 

6.5.5  Connection  to  Ancillary  Buildings 

Unless  otherwise  specified,  electric  connections  to 
ancillary  buildings,  such  as  out-houses,  garages,  etc, 
adjacent  to  the  main  building  and  when  no  roadway 
intervenes  shall  be  taken  in  an  earthed  GI  pipe  or  heavy 
duty  PVC  or  HDPE  pipe  of  suitable  size.  This  pipe  can 
be  taken  either  underground  or  over  ground,  however, 
in  latter  case,  its  height  from  the  ground  shall  not  be 
less  than  5.8  m.  This  applies  to  both  runs  of  mains  or 
sub-mains  or  final  sub-circuit  wiring  between  the 
buildings. 

6.5.6  Expansion  Joints 

Distribution  boards  shall  be  so  located  that  the  conduits 
shall  not  normally  be  required  to  cross  expansion  joints 
in  a  building.  Where  such  crossing  is  found  to  be 
unavoidable,  special  care  shall  be  taken  to  ensure  that 
the  conduit  runs  and  wiring  are  not  in  any  way  put  to 
strain  or  damaged  due  to  expansion  of  building 
structure.  Anyone  of  the  following  standard  methods 
of  connection  at  a  structural  expansion  joint  shall  be 
followed: 

a)  Flexible  conduit  shall  be  inserted  at  place  of 
expansion  joint. 

b)  Oversized  conduit  overlapping  the  conduit. 

c)  Expansion  box. 

Supports  and  flexible  joints  shall  be  of  same 
requirement  as  the  rising  main/bus  duct  in  so  far  as 
resistance  to  seismic  forces  is  concerned.  This  is  further 
important  when  rising  mains  and  bus-ducts  cross 
expansion  joints. 

6.5.7  Low  Voltage  ( Types  of  Wires/Cables) 

Low  voltage  services  utilizes  various  categories  of 
cables/wires,  such  as  fibre  optic  cable,  co-axial, 
category  cable,  etc.  These  shall  be  laid  at  least  at  a 
distance  of  300  mm  from  any  power  wire  or  cable.  The 
distance  may  be  reduced  only  by  using  completely 
closed  earthed  metal  trunking  with  metal  separations 
for  various  kind  of  cable.  Special  care  shall  be  taken  to 
ensure  that  the  conduit  runs  and  wiring  are  laid  properly 
for  low  voltage  signal  to  flow  through  it. 

The  power  cable  and  the  signal  or  data  cable  may  run 
together  under  floor  and  near  the  equipment.  However, 
separation  may  be  required  from  the  insulation  aspect, 
if  the  signal  cable  is  running  close  to  an  un-insulated 
conductor  carrying  power  at  high  voltage.  All  types  of 
signal  cables  are  required  to  have  insulation  level  for 
withstanding  2  kV  impulse  voltage  even  if  they  are 
meant  for  service  at  low  voltage. 


6.6  Joints  and  Looping  Back 

6.6.1  Where  looping  back  system  of  wiring  is  specified, 
the  wiring  shall  be  done  without  any  junction  or 
connector  boxes  on  the  line.  Where  joint  box  system  is 
specified,  all  joints  in  conductors  shall  be  made  by 
means  of  suitable  mechanical  connectors  in  suitable 
joint  boxes.  Whenever  practicable,  only  one  system 
shall  be  adopted  for  a  building,  preferably  a  looping 
back  system. 

6.6.2  In  any  system  of  wiring,  no  bare  or  twist  joints 
shall  be  made  at  intermediate  points  in  the  through  run 
of  cables  unless  the  length  of  a  final  sub-circuit,  sub- 
main  or  main  is  more  than  the  length  of  the  standard 
coil  as  given  by  the  manufacturer  of  the  cable.  If  any 
jointing  becomes  unavoidable  such  joint  shall  be  made 
through  proper  cutouts  or  through  proper  junction  boxes 
open  to  easy  inspection,  but  in  looping  back  system  no 
such  junction  boxes  shall  be  allowed. 

6.6.3  Joints  are  a  source  of  problems  in  reliability  and 
are  also  vulnerable  to  fire.  They  should  be  avoided  or 
at  least  minimized.  They  should  under  no  circumstance 
exceed  more  than  one  to  two  in  total  length  and  distance 
between  two  shall  not  be  less  than  5  m.  Joint  should 
not  be  used  as  tap-off  for  multiple  feeders.  Where  joints 
in  cable  conductors  or  bare  conductors  are  necessary, 
they  shall  be  mechanically  and  electrically  sound.  Joints 
in  non-flexible  cables  shall  be  accessible  for  inspection; 
provided  that  this  requirement  shall  not  apply  to  joints 
in  cables  buried  underground,  or  joints  buried  or 
enclosed  in  non-combustible  building  materials.  Joints 
in  non-flexible  cables  shall  be  made  by  soldering, 
brazing,  welding  or  mechanical  clamps,  or  be  of  the 
compression  type;  provided  that  mechanical  clamps 
shall  not  be  used  for  inaccessible  joints  buried  or 
enclosed  in  the  building  structure.  All  mechanical 
clamps  and  compression  type  sockets  shall  securely 
retain  all  the  wires  of  the  conductors.  Any  joint  in  a 
flexible  cable  or  flexible  cord  shall  be  effected  by  means 
of  a  cable  coupler. 

For  flexible  cables  for  small  loads  less  than  1  kW,  while 
it  is  desirable  to  avoid  joints,  if  unavoidable,  joints  may 
be  made  either  by  splicing  by  a  recognized  method  or 
by  using  a  connector  and  protecting  the  joint  by  suitable 
insulating  tape  or  sleeve  or  straight  joint.  For 
application  of  flexible  cable  for  loads  of  1  kW  or  more, 
if  joint  is  unavoidable,  crimped  joint  is  preferred. 
Spliced  joint  should  not  be  used  for  large  loads. 

There  are  different  standard  joints,  such  as  epoxy  resin 
based  joint,  heat  shrinkable  plastic  sleeve  joint,  etc, 
and  each  one  has  its  advantage  and  disadvantage. 
Selection  has  to  be  made  on  the  basis  of  application, 
site  conditions  and  availability  of  skilled  licensed 
workmen  trained  in  the  application  of  the  particular 
type  of  joint. 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


6.6.4  Every  joint  in  a  cable  shall  be  provided  with 
insulation  not  less  effective  than  that  of  the  cable  cores 
and  shall  be  protected  against  moisture  and  mechanical 
damage.  Soldering  fluxes  which  remain  acidic  or 
corrosive  at  the  completion  of  the  soldering  operation 
shall  not  be  used. 

For  joints  in  paper-insulated  metal-sheathed  cables,  a 
wiped  metal  sleeve  or  joint  box,  filled  with  insulating 
compound,  shall  be  provided. 

Where  an  aluminum  conductor  and  a  copper  conductor 
are  joined  together,  precautions  shall  be  taken  against 
corrosion  and  mechanical  damage  to  the  conductors. 

6.6.5  Pull  at  Joints  and  Terminals 

Every  connection  at  a  cable  termination  shall  be  made 
by  means  of  a  terminal,  soldering  socket,  or 
compression  type  socket  and  shall  securely  contain  and 
anchor  all  the  wires  of  the  conductor,  and  shall  not 
impose  any  appreciable  mechanical  strain  on  the 
terminal  or  socket. 

Flexible  cords  shall  be  so  connected  to  devices  and  to 
fittings  that  tension  is  not  transmitted  to  joints  or 
terminal  screws.  This  shall  be  accomplished  by  a  knot 
in  the  cord,  by  winding  with  tape,  by  a  special  fitting 
designed  for  that  purpose,  or  by  other  approved  means 
which  can  prevent  a  pull  on  the  cord  from  being  directly 
transmitted  to  joints  or  terminal  screws. 

6.7  Passing  Through  Walls  and  Floors 

6.7.1  Where  wires/cables  are  required  to  pass  through 
walls,  care  shall  be  taken  to  see  that  wires/cables  pass 
freely  through  protective  pipe  or  box  and  that  the  wires 
pass  through  in  a  straight  line  without  any  twist  or  cross 
in  wires. 

One  of  the  following  methods  shall  be  employed  for 
laying  wires/cables: 

a)  Conduit  wiring  system  ( see  6.10)  —  The 
conductor  shall  be  carried  either  in  a  rigid  steel 
conduit  or  a  rigid  non-metallic  conduit 
conforming  to  accepted  standards  [8-2(33)]. 
The  conduits  shall  be  colour  coded  as  per  the 
purpose  of  wire  carried  in  the  same.  The 
recommended  colour  coding  may  be  in  form 
of  bands  of  colour  ( 1 00  mm  thick,  with  centre 
to  centre  distance  of  300  mm)  or  coloured 
throughout.  The  colour  scheme  may  be  as 
follows: 

Conduit  Type  Colour  Scheme 

Power  conduit  Black 

Security  conduit  Blue 

Fire  alarm  conduit  Red 

Low  voltage  conduit  Brown 

UPS  conduit  Green 


Conduit  wiring  system  shall  comply  with 
accepted  standards  [8-2(34)].  The  number  of 
insulated  conductors  that  can  be  drawn  into 
rigid  conduit  is  given  in  Tables  1  (see  Table 
1A  for  rigid  steel  conduits  and  Table  IB  for 
rigid  non-metallic  conduits). 

b)  Cable  trunking/cable  ways  (see  6.11)  —  Cable 
trunking/cable  ways  system  should  be  used 
when  number  of  wires/small  cable  sizes  to  be 
laid  is  more  than  the  conduit  capacity.  Care 
should  be  taken  to  have  space  in  the  trunking 
system  to  minimize  heating  of  wires  and  to 
provide  identification  of  the  different  circuits. 
Cable  trunking  or  ducting  system  shall  comply 
with  accepted  standards  [8-2(35)]. 

c)  Tray  and  ladder  rack  —  As  tray  provides 
continuous  support,  unless  mounted  on  edge 
or  in  vertical  runs  (when  adequate  strapping 
or  clipping  is  essential),  the  mechanical 
strength  of  supported  cable  is  not  as  important 
as  with  ladder-racking  or  structural  support 
methods.  Consequently,  tray  is  eminently 
suitable  for  the  smaller  unarmoured  cabling 
while  ladder  racks  call  for  armoured  cables 
or  larger  unarmoured  cables  as  they  provide 
the  necessary  strength  to  avoid  sagging 
between  supports.  Both  tray  and  ladder  racks 
are  provided  with  accessories  to  facilitate 
changes  of  route,  and  they  provide  no 
difficulty  in  this  respect  on  vertical  runs. 
Cable  tray/ladder  racks  and  support  systems 
shall  be  installed  in  such  a  way  that  the 
deflection  between  the  spans  shall  be  less  than 
1  percent  of  the  span. 

Power  cables  running  in  cable  ladders  both 
horizontal  and  vertical  shall  be  fixed  with 
proper  clamps  which  can  withstand  the 
mechanical  force  created  on  the  cable  in  case 
of  short  circuit  current.  The  complete 
installation  consisting  of  cables,  ladders, 
clamps,  ladder  supports  and  fixtures  shall  also 
withstand  the  mechanical  force  of  short  circuit 
current.  Only  one  layer  of  power  cable  shall 
be  laid  in  a  ladder.  The  minimum  space 
between  two  cables  shall  be  equal  to  the 
diameter  of  the  biggest  cable. 

Cable  tray  and  ladder  system  shall  comply 
with  IEC  61537:2006  ‘Cable  management  — 
Cable  tray  systems  and  cable  ladder  systems’ 
(under  publication  as  an  adopted  Indian 
Standard). 

6.7.2  Insulated  conductors  while  passing  through  floors 
shall  be  protected  from  mechanical  injury  by  means  of 
rigid  steel/non-metal  conduit  or  by  mechanical 
protection  up  to  a  height  not  less  than  1.5  m  above  the 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


51 


floor  and  flush  with  the  ceiling  below.  These  steel 
conduits  shall  be  earthed  and  securely  bushed. 

Power  outlets  and  wiring  in  the  floor  shall  be  generally 
avoided.  If  not  avoidable,  false  floor  trunking  or  metal 
floor  trunking  should  be  used.  Power  sockets  of 
adequate  IP/IK  rating  shall  be  used. 

False  floor  shall  be  provided  where  density  of 
equipment  and  interconnection  between  different  pieces 
of  equipment  is  high.  Examples  are,  mainframe 
computer  station,  telecommunication  switch  rooms,  etc. 
Floor  trunking  shall  be  used  in  large  halls,  convention 
centres,  open  plan  offices,  laboratory,  etc. 

In  case  of  floor  trunking,  drain  points/weep  holes  shall 
be  provided  within  the  trunking  for  installation  for 
conventional  centres,  exhibition  areas  or  any  other  place 
where  water  may  spill  into  the  trunking,  as  there  might 
be  possibility  of  water  seepage  in  the  case  of  wiring 
passing  through  the  floors.  Proper  care  should  be  taken 
for  providing  suitable  means  of  draining  of  water. 
Possibility  of  water  entry  exists  from  floor  washing, 
condensation  in  some  particular  weather  and  indoor 
temperature  conditions.  At  the  design  stage,  these 
aspects  shall  be  assessed  and  an  appropriate  means  of 
avoiding,  or  reducing,  and  draining  method  shall  be 
built  in.  Floor  trunking  outlets  shall  be  suitably  IP  rated 
for  protection  against  dust  and  water. 

Floor  outlet  boxes  are  generally  provided  for  the  use 
of  appliances,  which  require  a  signal,  or  communication 
connection.  The  floor  box  and  trunking  system  should 
cater  to  serve  both  power  distribution  and  the  signal 
distribution,  with  appropriate  safety  and  non¬ 
interference. 

6.7.3  Where  a  wall  tube  passes  outside  a  building  so  as 
to  be  exposed  to  weather,  the  outer  end  shall  be  bell¬ 
mouthed  and  turned  downwards  and  properly  bushed 
on  the  open  end. 

6.8  Wiring  of  Distribution  Boards 

6.8.1  All  connections  between  pieces  of  apparatus  or 
between  apparatus  and  terminals  on  a  board  shall  be 
neatly  arranged  in  a  definite  sequence,  following  the 
arrangements  of  the  apparatus  mounted  thereon, 
avoiding  unnecessary  crossings. 

6.8.2  Cables  shall  be  connected  to  a  terminal  only  by 
soldered  or  welded  or  crimped  lugs  using  suitable 
sleeve,  lugs  or  ferrules  unless  the  terminal  is  of  such  a 
form  that  it  is  possible  to  securely  clamp  them  without 
the  cutting  away  of  cables  stands.  Cables  in  each  circuit 
shall  be  bunched  together. 

6.8.3  All  bare  conductors  shall  be  rigidly  fixed  in  such 
a  manner  that  a  clearance  of  at  least  25  mm  is 
maintained  between  conductors  or  opposite  polarity  or 


phase  and  between  the  conductors  and  any  material 
other  than  insulation  material. 

6.8.4  If  required,  a  pilot  lamp  shall  be  fixed  and 
connected  through  an  independent  single  pole  switch 
and  fuse  to  the  bus-bars  of  the  board.  Leads  connecting 
bus-bars  to  any  instrument  or  indicating  lamp  or  an 
outgoing  connection  switch  or  breaker  face  the  same 
fault  current  that  is  applicable  to  the  bus-bar  and  as 
such  should  be  provided  with  a  fuse  capable  of  handling 
the  prospective  fault  current. 

6.8.5  In  a  hinged  type  board,  the  incoming  and  outgoing 
cables  shall  be  fixed  at  one  or  more  points  according 
to  the  number  of  cables  on  the  back  of  the  board  leaving 
suitable  space  in  between  cables,  and  shall  also,  if 
possible,  be  fixed  at  the  corresponding  points  on  the 
switchboard  panel.  The  cables  between  these  points 
shall  be  of  such  length  as  to  allow  the  switchboard  panel 
to  swing  through  an  angle  of  not  less  than  90°  and  cables 
arranged  and  clamped  in  such  a  manner  that  the  cables 
do  not  face  bending,  but  only  face  a  twist,  when  the 
hinged  door  is  opened.  The  circuit  breakers  in  such 
cases  shall  be  accessible  without  opening  the  door  of 
distribution  board.  Also,  circuit  breakers  or  any  other 
equipment  (having  cable  size  more  than  1.5  mm2  multi¬ 
strand  wire)  shall  not  be  mounted  on  the  door. 

NOTE  —  Use  of  hinged  type  boards  is  discouraged,  as  these 
boards  lead  to  deterioration  of  the  cables  in  the  hinged  portion, 
leading  to  failures  or  even  fire. 

6.8.6  Wires  terminating  and  originating  from  the 
protective  devices  shall  be  properly  lugged  and  taped. 

6.9  PVC-Sheathed  Wiring  System 

6.9.1  General 

Wiring  with  PVC-sheathed  cables  may  be  used  for 
temporary  installations  for  medium  voltage  installation 
and  may  be  installed  directly  under  exposed  conditions 
of  sun  and  rain  or  damp  places. 

6.9.2  PVC  Clamps/PVC  Channel 

The  clamps  shall  be  used  for  temporary  installations 
of  1-3  sheathed  wires  only.  The  clamps  shall  be  fixed 
on  wall  at  intervals  of  1 00  mm  in  the  case  of  horizontal 
runs  and  150  mm  in  the  case  of  vertical  runs. 

PVC  channel  shall  be  used  for  temporary  installations 
in  case  more  than  3  wires  or  wires  or  unsheathed  wires. 
The  channel  shall  be  clamped  on  wall  at  intervals  not 
exceeding  300  mm.  PVC  clamps/PVC  channel  shall 
conform  to  accepted  standards. 

6.9.3  Protection  of  PVC-Sheathed  Wiring  from 
Mechanical  Damage 

a)  In  cases  where  there  are  chances  of  any 
damage  to  the  wirings,  such  wirings  shall  be 


52 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


covered  with  sheet  metal  protective  covering, 
the  base  of  which  is  made  flush  with  the  plaster 
or  brickwork,  as  the  case  may  be,  or  the  wiring 
shall  be  drawn  through  a  conduit  complying 
with  all  requirements  of  conduit  wiring  system 
(see  6.10). 

b)  Such  protective  coverings  shall  in  all  cases 
be  fitted  on  all  down-drops  within  1.5  m  from 
the  floor. 

6.9.4  Bends  in  Wiring 

The  wiring  shall  not  in  any  circumstances  be  bent  so  as 
to  form  a  right  angle  but  shall  be  rounded  off  at  the 
comers  to  a  radius  not  less  than  six  times  the  overall 
diameter  of  the  cable. 

6.9.5  Passing  Through  Floors 

All  cables  taken  through  floors  shall  be  enclosed  in  an 
insulated  heavy  gauge  steel  conduit  extending  1.5  m 
above  the  floor  and  flush  with  the  ceiling  below,  or  by 
means  of  any  other  approved  type  of  metallic  covering. 
The  ends  of  all  conduits  or  pipes  shall  be  neatly  bushed 
with  porcelain,  wood  or  other  approved  material. 

6.9.6  Passing  Through  Walls 

The  method  to  be  adopted  shall  be  according  to  good 
practice.  There  shall  be  one  or  more  conduits  of 
adequate  size  to  carry  the  conductors  [see  6.10.1(a)], 
The  conduits  shall  be  neatly  arranged  so  that  the  cables 
enter  them  straight  without  bending. 

6.9.7  Stripping  of  Outer  Covering 

While  cutting  and  stripping  of  the  outer  covering  of 
the  cables,  care  shall  be  taken  that  the  sharp  edge  of 
the  cutting  instrument  does  not  touch  the  rubber  or 
PVC-sheathed  insulation  of  conductors.  The  protective 
outer  covering  of  the  cables  shall  be  stripped  off  near 
connecting  terminals,  and  this  protective  covering  shall 
be  maintained  up  to  the  close  proximity  of  connecting 
terminals  as  far  as  practicable.  Care  shall  be  taken  to 
avoid  hammering  on  link  clips  with  any  metal 
instruments,  after  the  cables  are  laid.  Where  junction 
boxes  are  provided,  they  shall  be  made  moisture-proof 
with  an  approved  plastic  compound. 

6.9.8  Painting 

If  so  required,  the  tough  rubber-sheathed  wiring  shall, 
after  erection,  be  painted  with  one  coat  of  oil-less  paint 
or  distemper  of  suitable  colour  over  a  coat  of  oil-less 
primer,  and  the  PVC-sheathed  wiring  shall  be  painted 
with  a  synthetic  enamel  paint  of  quick  drying  type. 

6.10  Conduit  Wiring  System 

Conduit  wiring  system  shall  comply  with  accepted 
standards  [8-2(34)].  Requirements  relating  to  conduit 


wiring  system  with  rigid  steel  and  non-metallic  conduits 
shall  be  as  per  6.10.1  to  6.10.3. 

6.10.1  Surface  Conduit  Wiring  System  with  Rigid  Steel 
Conduits 

a)  Type  and  size  of  conduit  —  All  conduit  pipes 
shall  conform  to  accepted  standards  [8-2(36)], 
finished  with  galvanized  or  enamelled  surface. 
All  conduit  accessories  shall  be  of  threaded 
type  and  under  no  circumstance  pin  grip  type 
or  clamp  type  accessories  be  used.  No  steel 
conduit  less  than  16  mm  in  diameter  shall  be 
used.  The  number  of  insulated  conductors  that 
can  be  drawn  into  rigid  steel  conduit  is  given 
in  Tables  1A. 

b)  Bunching  of  cables  —  Unless  otherwise 
specified,  insulated  conductors  of  a.c.  supply 
and  d.c.  supply  shall  be  bunched  in  separate 
conduits.  For  lighting  and  small  power  outlet 
circuits  phase  segregation  in  separate  conduits 
is  recommended. 

c)  Conduit  joints  —  Conduit  pipes  shall  be  joined 
by  means  of  screwed  couplers  and  screwed 
accessories  only  [see  8-2(37)].  In  long  distance 
straight  runs  of  conduit,  inspection  type 
couplers  at  reasonable  intervals  shall  be 
provided  or  running  threads  with  couplers  and 
jam-nuts  (in  the  latter  case  the  bare  threaded 
portion  shall  be  treated  with  anti-corrosive 
preservative)  shall  be  provided.  Threaded  on 
conduit  pipes  in  all  cases  shall  be  between  1 1 
mm  and  27  mm  long  sufficient  to  accommodate 
pipes  to  full  threaded  portion  of  couplers  or 
accessories.  Cut  ends  of  conduit  pipes  shall 
have  no  sharp  edges  or  any  burrs  left  to  avoid 
damage  to  the  insulation  of  conductors  while 
pulling  them  through  such  pipes. 

d)  Protection  against  dampness  —  In  order  to 
minimize  condensation  or  sweating  inside  the 
tube,  all  outlets  of  conduit  system  shall  be 
properly  drained  and  ventilated,  but  in  such  a 
manner  as  to  prevent  the  entry  of  insects  as 
far  as  possible. 

e)  Protection  of  conduit  against  rust  —  The 
outer  surface  of  the  conduit  pipes,  including 
all  bends,  unions,  tees,  conduit  system  shall 
be  adequately  protected  against  rust 
particularly  when  such  system  is  exposed  to 
weather.  In  all  cases,  no  bare  threaded  portion 
of  conduit  pipe  shall  be  allowed  unless  such 
bare  threaded  portion  is  treated  with  anti¬ 
corrosive  preservative  or  covered  with  suitable 
plastic  compound. 

f)  Fixing  of  conduit  —  Conduit  pipes  shall  be 
fixed  by  heavy  gauge  saddles,  secured  to 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


53 


Table  1A  Maximum  Permissible  Number  of  Single-Core  Cables  up  to  and  including  1 100  V 
that  can  be  Drawn  into  Rigid  Steel  Conduits 

[ Clauses  6.7.1(a)  and  6.10.1(a)] 


SI 

No. 

Size  of  Cable 

Size  of  Conduit 

mm 

Nominal 

Cross- 

Number 

and 

16 

20 

25 

32  40 

Number  of  Cables,  Max 

50 

63 

Area 

mm* 2 

(in  mm)  of 
Wires 

'  S  B  ' 

'  S  B  ' 

S 

B 

s  b'  s 

B 

s  b' 

's 

B 

(1) 

(2) 

(3) 

(4)  (5) 

(6)  (7) 

(8) 

(9) 

(10)  (11)  (12) 

(13) 

(14)  (15) 

(16) 

(17) 

i) 

1.0 

1/1.121) 

5 

4 

7 

5 

13 

10 

20 

14 

— 

— 

— 

— 

— 

— 

ii) 

1.5 

1/1.40 

4 

3 

7 

5 

12 

10 

20 

14 

— 

— 

— 

— 

— 

— 

ill) 

2.5 

1/1.80 

3/1 .06" 

3 

2 

6 

5 

10 

8 

18 

12 

— 

— 

— 

— 

— 

— 

iv) 

4 

1/2.24 

7/0.85" 

3 

2 

4 

3 

7 

5 

12 

10 

— 

— 

— 

— 

— 

— 

v) 

6 

1/2.80 

7/1.06" 

2 

— 

3 

2 

6 

5 

10 

8 

— 

— 

— 

— 

— 

— 

vi) 

10 

1/3.55" 

— 

— 

2 

— 

5 

4 

8 

7 

— 

— 

— 

— 

— 

— 

7/1.40" 

— 

— 

2 

— 

4 

3 

6 

5 

8 

6 

— 

— 

— 

— 

vii) 

16 

7/1.70 

— 

— 

— 

— 

2 

— 

4 

3 

7 

6 

— 

— 

— 

— 

viii) 

25 

7/2.24 

— 

— 

— 

— 

— 

— 

3 

2 

5 

4 

8 

6 

9 

7 

ix) 

35 

7/2.50 

— 

— 

— 

— 

— 

— 

2 

— 

4 

3 

7 

5 

8 

6 

x) 

50 

19/1.80 
7/3. 007" 

2 

5 

4 

6 

5 

NOTES 

1  The  table  shows  the  maximum  capacity  of  conduits  for  the  simultaneously  drawing  of  cables.  The  columns  headed  S  apply  to  runs 
of  conduit  which  have  distance  not  exceeding  4.25  m  between  draw-in  boxes,  and  which  do  not  deflect  from  the  straight  by  an  angle 
of  more  than  15°.  The  columns  headed  B  apply  to  runs  of  conduit  which  deflect  from  the  straight  by  an  angle  of  more  than  15°. 

2  In  case  an  inspection  type  draw-in  box  has  been  provided  and  if  the  cable  is  first  drawn  through  one  straight  conduit,  then  through  the 
draw-in  box,  and  then  through  the  second  straight  conduit,  such  systems  may  be  considered  as  that  of  a  straight  conduit  even  if  the 
conduit  deflects  through  the  straight  by  more  than  15°. 

3  Conductor  sizes  for  cables  and  wires  above  and  including  2.5  mm2  core  size  shall  be  multi-stranded. 


For  copper  conductors  only. 

2)  For  aluminium  conductors  only. 


suitable  wood  plugs  or  other  plugs  with  screws 
in  an  approved  manner  at  an  interval  of  not 
more  than  1  m,  but  on  either  side  of  couplers 
or  bends  or  similar  fittings,  saddles  shall  be 
fixed  at  a  distance  of  300  mm  from  the  centre 
of  such  fittings.  Conduit  fittings  shall  be 
avoided  as  far  as  possible  on  conduit  system 
exposed  to  weather;  where  necessary,  solid 
type  fittings  shall  be  used, 
g)  Bends  in  conduit  —  All  necessary  bends  in 
the  system  including  diversion  shall  be  done 
by  bending  pipes;  or  by  inserting  suitable  solid 
or  inspection  type  normal  bends,  elbows  or 
similar  fittings;  or  fixing  cast  iron, 
thermoplastic  or  thermosetting  plastic  material 
inspection  boxes,  whichever  is  more  suitable. 
Radius  of  such  bends  in  conduit  pipes  shall 
be  not  less  than  75  mm.  No  length  of  conduit 
shall  have  more  than  the  equivalent  of  four 
quarter  bends  from  outlet  to  outlet,  the  bends 
at  the  outlets  not  being  counted. 


h)  Outlets  —  All  outlets  for  fittings,  switches, 
etc,  shall  be  boxes  of  suitable  metal  or  any 
other  approved  outlet  boxes  for  either  surface 
mounting  or  flush  mounting  system. 

j)  Conductors  —  All  conductors  used  in  conduit 
wiring  shall  preferably  be  stranded.  No  single¬ 
core  cable  of  nominal  cross-sectional  area 
greater  than  130  mm2  enclosed  along  in  a 
conduit  and  used  for  alternating  current. 

k)  Erection  and  earthing  of  conduit  —  The 
conduit  of  each  circuit  or  section  shall  be 
completed  before  conductors  are  drawn  in. 
The  entire  system  of  conduit  after  erection 
shall  be  tested  for  mechanical  and  electrical 
continuity  throughout  and  permanently 
connected  to  earth  conforming  to  the 
requirements  as  already  specified  by  means 
of  suitable  earthing  clamp  efficiently  fastened 
to  conduit  pipe  in  a  workman  like  manner  for 
a  perfect  continuity  between  each  wire  and 
conduit.  Gas  or  water  pipes  shall  not  be  used 


54 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


as  earth  medium.  If  conduit  pipes  are  liable  to 
mechanical  damage  they  shall  be  adequately 
protected. 

m)  Inspection  type  conduit  fittings,  such  as 
inspection  boxes,  draw  boxes,  bends,  elbows 
and  tees  shall  be  so  installed  that  they  can 
remain  accessible  for  such  purposes  as  to 
withdrawal  of  existing  cables  or  the  installing 
of  traditional  cables. 

6.10.2  Recessed  Conduit  Wiring  System  with  Rigid  Steel 
Conduit 

Recessed  conduit  wiring  system  shall  comply  with  all 
the  requirements  for  surface  conduit  wiring  system 
specified  in  6.10.1  (a)  to  6.10.1  (k)  and  in  addition, 
conform  to  the  requirements  specified  below: 

a)  Making  of  chase  —  The  chase  in  the  wall  shall 
be  neatly  made  and  be  of  ample  dimensions 
to  pennit  the  conduit  to  be  fixed  in  the  manner 
desired.  In  the  case  of  buildings  under 
construction,  chases  shall  be  provided  in  the 
wall,  ceiling,  etc,  at  the  time  of  their 
construction  and  shall  be  filled  up  neatly  after 
erection  of  conduit  and  brought  to  the  original 
finish  of  the  wall.  In  case  of  exposed  brick/ 
rubble  masonry  work,  special  care  shall  be 
taken  to  fix  the  conduit  and  accessories  in 
position  along  with  the  building  work. 

b)  Fixing  of  conduit  in  chase  —  The  conduit  pipe 
shall  be  fixed  by  means  of  staples  or  by  means 
of  saddles  not  more  than  600  mm  apart.  Fixing 
of  standard  bends  or  elbows  shall  be  avoided 
as  far  as  practicable  and  all  curves  maintained 
by  bending  the  conduit  pipe  itself  with  a  long 
radius  which  will  permit  easy  drawing-in  of 
conductors.  All  threaded  joints  of  rigid  steel 
conduit  shall  be  treated  with  preservative 
compound  to  secure  protection  against  rust. 

c)  Inspection  boxes  —  Suitable  inspection  boxes 
shall  be  provided  to  permit  periodical 
inspection  and  to  facilitate  removal  of  wires, 
if  necessary.  These  shall  be  mounted  flush  with 
the  wall.  Suitable  ventilating  holes  shall  be 
provided  in  the  inspection  box  covers.  The 
minimum  sizes  of  inspection  boxes  shall  be 
75  mm  x  75  mm. 

d)  Types  of  accessories  to  be  used  —  All  outlet, 
such  as  switches  and  wall  sockets,  may  be 
either  of  flush  mounting  type  or  of  surface 
mounting  type,  as  given  below: 

1)  Flush  mounting  type  —  All  flush 
mounting  outlets  shall  be  of  cast-iron  or 
mild  steel  boxes  with  a  cover  of  insulating 
material  or  shall  be  a  box  made  of  a 
suitable  insulating  material.  The  switches 


and  other  outlets  shall  be  mounted  on  such 
boxes.  The  metal  box  shall  be  efficiently 
earthed  with  conduit  by  a  suitable  means 
of  earth  attachment. 

2)  Surface  mounting  type  —  If  surface 
mounting  type  outlet  box  is  specified,  it 
shall  be  of  any  suitable  insulating  material 
and  outlets  mounted  in  an  approved 
manner. 

The  switches/socket  outlets  shall  have 
adequate  IP  rating  for  various  utilizations. 

6. 1 0.3  Conduit  Wiring  System  with  Rigid  Non-Metallic 
Conduits 

Rigid  non-metallic  conduits  are  used  for  concealed 
conduit  wiring. 

6.10.3.1  Type  and  size 

All  non-metallic  conduits  used  shall  conform  to 
accepted  standards  [8-2(38)]  and  shall  be  used  with 
the  corresponding  accessories  {see  accepted  standards 
[8-2(39)]} .  The  conduits  shall  be  circular  or  rectangular 
cross-sections. 

6.10.3.2  Bunching  of  cables 

Conductors  of  a.c.  supply  and  d.c.  supply  shall  be 
bunched  in  separate  conduits.  For  lighting  and  small 
power  outlet  circuits  phase  segregation  in  separate 
circuits  is  recommended.  The  number  of  insulated 
cables  that  may  be  drawn  into  the  conduits  are  given  in 
Table  1  B.  In  Table  IB,  the  space  factor  does  not  exceed 
40  percent. 

6.10.3.3  Conduit  Joints 

Conduits  shall  be  joined  by  means  of  couplers.  Where 
there  are  long  runs  of  straight  conduit,  inspection  type 
couplers  shall  be  provided  at  intervals.  For  conduit 
fittings  and  accessories  reference  may  be  made  to  the 
good  practice  [8-2(39)]. 

6.10.3.4  Fixing  of  conduit  in  chase 

The  conduit  pipe  shall  be  fixed  by  means  of  stapples 
or  by  means  of  non-metallic  saddles  placed  at  not  more 
than  800  mm  apart  or  by  any  other  approved  means  of 
fixing.  Fixing  of  standard  bends  or  elbows  shall  be 
avoided  as  far  as  practicable  and  all  curves  shall  be 
maintained  by  sending  the  conduit  pipe  itself  with  a 
long  radius  which  will  permit  easy  drawing  in  of 
conductors.  At  either  side  of  bends,  saddles/stapples 
shall  be  fixed  at  a  distance  of  150  mm  from  the  centre 
of  bends. 

6.10.3.5  Inspection  boxes 

Suitable  inspection  boxes  to  the  nearest  minimum 
requirements  shall  be  provided  to  permit  periodical 
inspection  and  to  facilitate  replacement  of  wires,  if 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


55 


Table  IB  Maximum  Permissible  Number  of  250  V  Grade  Single-Core  Cables  that  may  be 
Drawn  into  Rigid  Non-Metallic  Conduits 

[Clauses  6.7.1(a)  and  6.10.3.2] 


SI 

Sizes  of  Cable 

Size  of  Conduit 

No. 

mm 

Nominal  Cross- 

■''N 

Number  and 

16 

20 

25 

32 

40 

50 

Sectional  Area 

Diameter  (in  mm) 

Number  of  Cables,  Max 

mm2 

of  Wires 

(1) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

(9) 

i) 

1.0 

1/1.121) 

5 

7 

13 

20 

— 

— 

ii) 

1.5 

1/1.40 

4 

6 

10 

14 

— 

— 

iii) 

2.5 

(1/1.80) 

[3/1. 06u] 

3 

5 

10 

14 

— 

— 

iv) 

4 

(1/2.24) 

[7/0.85°] 

2 

3 

6 

10 

14 

v) 

6 

(1/2.80) 

[7/1.40"] 

2 

5 

9 

11 

Vi) 

10 

[1/3.5521] 

[7/1.40"] 

4 

7 

9 

vii) 

16 

7/1.70 

— 

— 

2 

4 

5 

12 

viii) 

25 

7/2.24 

— 

— 

— 

2 

2 

6 

ix) 

35 

7/2.50 

— 

— 

— 

— 

2 

5 

x) 

50 

7/3.002' 

— 

— 

— 

— 

2 

5 

19/1.80 

— 

— 

— 

— 

2 

3 

"  For  copper  conductors  only. 

2)  For  aluminium  conductors  only. 


necessary.  The  inspection/junction  boxes  shall  be 
mounted  flush  with  the  wall  or  ceiling  concrete.  Where 
necessary  deeper  boxes  of  suitable  dimensions  shall 
be  used.  Suitable  ventilating  holes  shall  be  provided  in 
the  inspection  box  covers,  where  required. 

6.10.3.6  The  outlet  boxes  such  as  switch  boxes, 
regulator  boxes  and  their  phenolic  laminated  sheet 
covers  shall  be  as  per  requirements  of  6. 10.1  (h).  They 
shall  be  mounted  flush  with  the  wall. 

6.10.3.7  Types  of  accessories  to  be  used 

All  accessories  such  as  switches,  wall  sockets,  etc,  may 
be  either  flush  mounting  type  or  of  surface  mounting 

type- 

6.10.3.8  Bends  in  conduits 

Wherever  necessary,  bends  or  diversions  may  be 
achieved  by  bending  the  conduits  or  by  employing 
normal  bends,  inspection  bends,  inspection  boxes, 
elbows  or  similar  fittings.  Heat  may  be  used  to  soften 
the  conduit  for  bending  and  forming  joints  in  case  of 
plain  conduits. 

6.10.3.9  Outlets 

In  order  to  minimize  condensation  or  sweating  inside 
the  conduit,  all  outlets  of  conduit  system  shall  be 
properly  drained  and  ventilated,  but  in  such  a  manner 
as  to  prevent  the  entry  of  insects. 

6.11  Cable  Trunking/Cable  Ways 

Cable  trunking  and  ducting  system  of  insulating 


material  are  used  for  surface  wiring.  The  number  of 
insulated  conductors  that  can  be  drawn  into  cable 
trunking  and  ducting  system  are  given  in  Table  2. 

7  FITTINGS  AND  ACCESSORIES 

7.1  Ceiling  Roses  and  Similar  Attachments 

7.1.1  A  ceiling  rose  or  any  other  similar  attachment 
shall  not  be  used  on  a  circuit  the  voltage  of  which 
normally  exceeds  250  V. 

7.1.2  Normally,  only  one  flexible  cord  shall  be  attached 
to  a  ceiling  rose.  Specially  designed  ceiling  roses  shall 
be  used  for  multiple  pendants. 

7.1.3  A  ceiling  rose  shall  not  embody  fuse  terminal  as 
an  integral  part  of  it. 

7.2  Socket-Outlets  and  Plugs 

Each  16  A  socket-outlet  provided  in  buildings  for  the 
use  of  domestic  appliances,  such  as,  air  conditioner  and 
water  cooler  shall  be  provided  with  its  own  individual 
fuse,  with  suitable  discrimination  with  back-up  fuse  or 
miniature  circuit-breaker  provided  in  the  distribution/ 
sub-distribution  board.  The  socket-outlet  shall  not 
necessarily  embody  the  fuse  as  an  integral  part  of  it. 

7.2.1  Each  socket-outlet  shall  also  be  controlled  by  a 
switch  which  shall  preferably  be  located  immediately 
adjacent  thereto  or  combined  therewith. 

7.2.2  The  switch  controlling  the  socket-outlet  shall  be 
on  the  live  side  of  the  line. 


56 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


Table  2  Maximum  Permissible  Number  of  PVC  Insulated  650/1  100  V  Grade  Aluminium/Copper  Cable 
Conforming  to  Accepted  Standard  [8-2(3)]  that  can  be  Drawn  into  Cable  Trunking/Cable  Ways 

( Clause  6.1 1) 


SI 

Nominal  Cross- 

10/15  mm  x 

20/15  mm  x 

25/15  mm  x 

32  mm  x 

40  mm  x 

40  mm  x 

No. 

Sectional  Area 
of  Conductor 

10  mm 

10  mm 

16  mm 

16  mm 

25  mm 

40  mm 

mm2 

(1) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

i) 

1.5 

3 

5 

6 

8 

12 

18 

ii) 

2.5 

2 

4 

5 

6 

9 

15 

ill) 

4 

2 

3 

4 

5 

8 

12 

iv) 

6 

— 

2 

3 

4 

6 

9 

v) 

10 

.— • 

1 

2 

3 

5 

8 

vi) 

16 

— 

— 

1 

2 

4 

6 

vii) 

25 

— 

— 

— 

1 

3 

5 

viii) 

35 

— . 

— 

— 

2 

4 

ix) 

50 

— 

— 

■ 

— 

I 

3 

X) 

70 

— 

— 

— 

— 

1 

2 

7.2.3  Ordinary  socket-outlet  may  be  fixed  at  any 
convenient  place  at  a  height  above  200  mm  from  the 
floor  level  and  shall  be  away  from  danger  of  mechanical 
injury. 

NOTE  —  In  situations  where  a  socket-outlet  is  accessible  to 
children,  it  is  necessary  to  install  an  interlocked  plug  and  socket 
or  alternatively  a  socket-outlet  which  automatically  gets 
screened  by  the  withdrawal  of  plug.  In  industrial  premises 
socket-outlet  of  rating  20  A  and  above  shall  preferably  be 
provided  with  interlocked  type  switch. 

In  case  of  public  buildings,  to  facilitate  operation  of 
switches/socket-outlets  by  persons  with  disabilities 
and  the  elderly,  these  shall  be  installed  at  an  accessible 
height  for  reaching  and  operating,  between  800  mm 
and  1  100  mm  above  floor  level  and  shall  be  located 
at  a  minimum  of  600  mm  with  a  preference  of 
minimum  700  mm,  from  any  internal  corner  ( see  also 
B-7  of  Part  3  ‘Development  Control  Rules  and 
General  Building  Requirements’  of  the  Code).  They 
shall  be  so  fixed  so  as  to  be  away  from  danger  of 
mechanical  injury. 

NOTE  —  As  an  exception,  electrical  wall  socket  outlets, 
telephone  points  and  TV  sockets  can  be  located  at  a  minimum 
height  of  400  mm  above  floor  level. 

7.2.4  In  an  earthed  system  of  supply,  a  socket-outlet 
with  plug  shall  be  of  three-pin  or  five-pin  type  with  the 
third  or  fifth  terminal  connected  to  the  earth.  When 
such  socket-outlets  with  plugs  are  connected  to  any 
current  consuming  device  of  metal  or  any  non¬ 
insulating  material  or  both,  conductors  connecting  such 
current-consuming  devices  shall  be  of  flexible  cord  with 
an  earthing  core  and  the  earthing  core  shall  be  secured 
by  connecting  between  the  earth  terminal  of  plug  and 
the  body  of  current-consuming  devices. 

In  industrial  premises  three-phase  and  neutral  socket- 
outlets  shall  be  provided  with  a  earth  terminal  either  of 


pin  type  or  scrapping  type  in  addition  to  the  main  pins 
required  for  the  purpose. 

7.2.5  In  wiring  installations  for  residential  buildings, 
metal  clad  switch,  socket-outlet  and  plugs  shall  be  used 
for  power  wiring.  For  industrial  and  commercial 
application  socket  outlets  conforming  to  accepted 
standards  [8-2(25)]  with  suitable  circuit  breakers  shall 
be  used. 

NOTE  —  A  recommended  schedule  of  socket-outlets  in  a 

residential  building  is  given  below: 


SI 

Location 

Number  of 

Number  of 

No. 

6  A  Socket- 

16A 

Outlets 

Socket- 

Outlets 

(1) 

(2) 

(3) 

(4) 

i) 

Bed  room 

2  to  6 

2 

■i) 

Living  room 

2  to  4 

2 

iii) 

Kitchen 

2  to  8 

2 

iv) 

Dining  room 

2  to  4 

2 

v) 

Garage 

1 

1 

vi) 

For  refrigerator 

— 

1 

vii) 

For  air  conditioner 

— 

1  for  each 

viii) 

Verandah 

1  per 

10  m2 

i 

ix) 

Bathroom 

i 

i 

7.3  Lighting  Fittings 

7.3.1  A  switch  shall  be  provided  for  control  of  every 
lighting  fitting  or  a  group  of  lighting  fittings.  Where 
control  at  more  than  one  point  is  necessary  as  many 
two  way  or  intermediate  switches  may  be  provided  as 
there  are  control  points.  See  also  7.2.3. 

7.3.2  In  industrial  premises,  lighting  fittings  shall  be 
supported  by  suitable  pipe/conduits,  brackets  fabricated 
from  structural  steel,  steel  chains  or  similar  materials 
depending  upon  the  type  and  weight  of  the  fittings. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


57 


Where  a  lighting  fitting  is  supported  by  one  or  more 
flexible  cords,  the  maximum  weight  to  which  the  twin 
flexible  cords  may  be  subjected  shall  be  as  follows: 


SI 

Nominal  Cross- 

Maximum 

No. 

Sectional  Area 

Permissible 

of  Twin  Cord 

Weight 

mm2 

kg 

(1) 

(2) 

(3) 

i) 

0.5 

2 

ii) 

0.75 

3 

hi) 

1.0 

5 

IV) 

1.5 

5.3 

v) 

2.5 

8.8 

vi) 

4 

14.0 

7.3.3  No  flammable  shade  shall  form  a  part  of  lighting 
fittings  unless  such  shade  is  well  protected  against  all 
risks  of  fire.  Celluloid  shade  or  lighting  fittings  shall 
not  be  used  under  any  circumstances. 

7.3.4  General  and  safety  requirements  for  electrical 
lighting  fittings  shall  be  in  accordance  with  good 
practice  [8-2(40)]. 

7.3.5  The  lighting  fittings  shall  conform  to  accepted 
standards  [8-2(26)]. 

7.4  Fitting-Wire 

The  use  of  fitting- wire  shall  be  restricted  to  the  internal 
wiring  of  the  lighting  fittings.  Where  fitting- wire  is  used 
for  wiring  fittings,  the  sub-circuit  loads  shall  terminate 
in  a  ceiling  rose  or  box  with  connectors  from  which 
they  shall  be  carried  into  the  fittings. 

7.5  Lampholders 

Lampholders  for  use  on  brackets  and  the  like  shall  be 
in  accordance  with  accepted  standards  [8-2(41)]  and 
all  those  for  use  with  flexible  pendants  shall  be  provided 
with  cord  grips.  All  lampholders  shall  be  provided  with 
shade  carriers.  Where  centre-contact  Edison  screw 
lampholders  are  used,  the  outer  or  screw  contacts  shall 
be  connected  to  the  ‘middle  wire’,  the  neutral,  the 
earthed  conductor  of  the  circuit. 

7.6  Outdoor  Lamps 

External  and  road  lamps  shall  have  weatherproof  fittings 
of  approved  design  so  as  to  effectively  prevent  the  ingress 
of  moisture  and  dust.  Flexible  cord  and  cord  grip 
lampholders  shall  not  be  used  where  exposed  to  weather. 
In  verandahs  and  similar  exposed  situations  where 
pendants  are  used,  these  shall  be  of  fixed  rod  type. 

7.7  Lamps 

All  lamps  unless  otherwise  required  and  suitably 
protected,  shall  be  hung  at  a  height  of  not  less  than 


2.5  m  above  the  floor  level.  All  electric  lamps  and 
accessories  shall  conform  to  accepted  standards 
[8-2(42)].  Following  shall  also  be  ensured: 

a)  Portable  lamps  shall  be  wired  with  flexible 
cord.  Hand  lamps  shall  be  equipped  with  a 
handle  of  moulded  composition  or  other 
material  approved  for  the  purpose.  Hand 
lamps  shall  be  equipped  with  a  substantial 
guard  attached  to  the  lampholder  or  handle. 
Metallic  guards  shall  be  earthed  suitably. 

b)  A  bushing  or  the  equivalent  shall  be  provided 
where  flexible  cord  enters  the  base  or  stem  of 
portable  lamp.  The  bushing  shall  be  of 
insulating  material  unless  a  jacketted  type  of 
cord  is  used. 

c)  All  wiring  shall  be  free  from  short  circuits  and 
shall  be  tested  for  these  defects  prior  to  being 
connected  to  the  circuit. 

d)  Exposed  live  parts  within  porcelain  fixtures 
shall  be  suitably  recessed  and  so  located  as  to 
make  it  improbable  that  wires  will  come  in 
contact  with  them.  There  shall  be  a  spacing  of 
at  least  125  mm  between  live  parts  and  the 
mounting  plane  of  the  fixture. 

7.8  Fans,  Regulators  and  Clamps 

7.8.1  Ceiling  Fans 

Ceiling  fans  including  their  suspension  shall  conform 
to  accepted  standards  [8-2(43)]  and  to  the  following 
requirements: 

a)  Control  of  a  ceiling  fan  shall  be  through  its 
own  regulator  as  well  as  a  switch  in  series. 
See  also  7.2.3. 

b)  All  ceiling  fans  shall  be  wired  with  normal 
wiring  to  ceiling  roses  or  to  special  connector 
boxes  to  which  fan  rod  wires  shall  be  connected 
and  suspended  from  hooks  or  shackles  with 
insulators  between  hooks  and  suspension  rods. 
There  shall  be  no  joint  in  the  suspension  rod, 
but  if  joints  are  unavoidable  then  such  joints 
shall  be  screwed  to  special  couplers  of  50  mm 
minimum  length  and  both  ends  of  the  pipes  shall 
touch  together  within  the  couplers,  and  shall  in 
addition  be  secured  by  means  of  split  pins; 
alternatively,  the  two  pipes  may  be  welded.  The 
suspension  rod  shall  be  of  adequate  strength  to 
withstand  the  dead  and  impact  forces  imposed 
on  it.  Suspension  rods  should  preferably  be 
procured  along  with  the  fan. 

c)  Fan  clamps  shall  be  of  suitable  design 
according  to  the  nature  of  construction  of 
ceiling  on  which  these  clamps  are  to  be  fitted. 
In  all  cases  fan  clamps  shall  be  fabricated  from 
new  metal  of  suitable  sizes  and  they  shall  be 


58 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


as  close  fitting  as  possible.  Fan  clamps  for 
reinforced  concrete  roofs  shall  be  buried  with 
the  casting  and  due  care  shall  be  taken  that 
they  shall  serve  the  purpose.  Fan  clamps  for 
wooden  beams,  shall  be  of  suitable  flat  iron 
fixed  on  two  sides  of  the  beam  and  according 
to  the  size  and  section  of  the  beam  one  or  two 
mild  steel  bolts  passing  through  the  beam  shall 
hold  both  flat  irons  together.  Fan  clamps  for 
steel  joist  shall  be  fabricated  from  flat  iron  to 
fit  rigidly  to  the  bottom  flange  of  the  beam. 
Care  shall  be  taken  during  fabrication  that  the 
metal  does  not  crack  while  hammer  to  shape. 
Other  fan  clamps  shall  be  made  to  suit  the 
position,  but  in  all  cases  care  shall  be  taken  to 
see  that  they  are  rigid  and  safe. 

d)  Canopies  on  top  and  bottom  of  suspension 
rods  shall  effectively  conceal  suspensions  and 
connections  to  fan  motors,  respectively. 

e)  The  lead-in-wire  shall  be  of  nominal  cross- 
sectional  area  not  less  than  1.5  mm2  copper 
and  shall  be  protected  from  abrasion. 

f)  Unless  otherwise  specified,  the  clearance 
between  the  bottom  most  point  of  the  ceiling 
fan  and  the  floor  shall  be  not  less  than  2.4  m. 
The  minimum  clearance  between  the  ceiling 
and  the  plane  of  the  blades  shall  be  not  less 
than  300  mm. 

A  typical  arrangement  of  a  fan  clamp  is  given  in  Fig.  4. 

NOTE  —  All  fan  clamps  shall  be  so  fabricated  that  fans  revolve 
steadily. 

7.8.2  Exhaust  Fans 

For  fixing  of  an  exhaust  fan,  a  circular  hole  shall  be 
provided  in  the  wall  to  suit  the  size  of  the  frame  which 
shall  be  fixed  by  means  of  rag-bolts  embedded  in  the 
wall.  The  hole  shall  be  nearly  plastered  with  cement 
and  brought  to  the  original  finish  of  the  wall.  The 
exhaust  fan  shall  be  connected  to  exhaust  fan  point 
which  shall  be  wired  as  near  to  the  hole  as  possible  by 
means  of  a  flexible  cord,  care  being  taken  that  the  blades 
rotate  in  the  proper  direction. 

7.8.3  Fannage 

7.8.3. 1  Where  ceiling  fans  are  provided,  the  bay  sizes 
of  a  building,  which  control  fan  point  locations,  play 
an  important  part.  Fans  of  1  200/1  400  mm  sweep 
normally  cover  an  area  of  9  m2  to  10  m2  and  therefore 
in  general  purpose  office  buildings,  for  every  part  of  a 
bay  to  be  served  by  the  ceiling  fans,  it  is  necessary  that 
the  bays  shall  be  so  designed  that  full  number  of  fans 
can  be  suitably  located  for  the  bay,  otherwise  it  will 
result  in  ill-ventilated  pockets.  In  general,  fans  in  long 
halls  may  be  spaced  at  3  m  in  both  the  directions.  If 
building  modules  do  not  lend  themselves  for  proper 


positioning  of  the  required  number  of  ceiling  fans,  other 
fans  such  as,  air  circulators  or  bracket  fans  will  have  to 
be  employed  for  the  areas  uncovered  by  the  ceiling  fans. 
For  this,  suitable  electrical  outlets  shall  be  provided 
although  result  will  be  disproportionate  to  cost  on 
account  of  fans. 

7.8.3. 2  Proper  air  circulation  may  be  achieved  either 
by  larger  number  of  smaller  fans  or  smaller  number  of 
larger  fans.  The  economics  of  the  system  as  a  whole 
should  be  a  guiding  factor  in  choosing  the  number  and 
type  of  fans  and  their  locations.  For  design  guidelines 
in  this  regard,  reference  shall  be  made  to  Part  8 
‘Building  Services,  Section  1  Lighting  and  Natural 
Ventilation’  of  the  Code. 

7.8.3.3  Exhaust  fans  are  necessary  for  spaces,  such  as 
community  toilets,  kitchens  and  canteens,  and  godowns 
to  provide  the  required  number  of  air  changes  ( see 
Part  8  ‘Building  Services,  Section  3  Air  Conditioning, 
Heating  and  Mechanical  Ventilation’  of  the  Code). 
Since  the  exhaust  fans  are  located  generally  on  the  outer 
walls  of  a  room,  appropriate  openings  in  such  walls 
shall  be  provided  for,  in  the  planning  stage. 

NOTE  —  Exhaust  fan  requirement  is  based  on  the 
recommended  air  changes  ( see  Part  8  ‘Building  Services, 
Section  3  Air  Conditioning,  Heating  and  Mechanical 
Ventilation’  of  the  Code).  Reference  shall  also  be  made  to  Part 
4  ‘Fire  and  Life  Safety’  of  the  Code  for  exhaust  fan  requirements 
for  smoke  extraction. 

7.9  Attachment  of  Fittings  and  Accessories 

7.9.1  In  wiring  other  than  conduit  wiring,  all  ceiling 
roses,  brackets,  pendants  and  accessories  attached  to 
walls  or  ceilings  shall  be  mounted  on  substantial  teak 
wood  blocks  twice  varnished  after  all  fixing  holes  are 
made  in  them.  Blocks  shall  not  be  less  than  40  mm 
deep.  Brass  screws  shall  only  be  used  for  attaching 
fittings  and  accessories  to  their  base  blocks. 

7.9.2  Where  teak  or  hardwood  boards  are  used  for 
mounting  switches,  regulators,  etc,  these  boards  shall 
be  well  varnished  with  pure  shellac  on  all  four  sides  (both 
inside  and  outside),  irrespective  of  being  painted  to  match 
the  surroundings.  The  size  of  such  boards  shall  depend 
on  the  number  of  accessories  that  can  be  conveniently 
and  neatly  be  arranged.  Where  there  is  danger  of  attack 
by  white  ants,  the  boards  shall  be  treated  with  suitable 
anti-termite  compound  and  painted  on  both  sides. 

7.10  Interchangeability 

Similar  parts  of  all  switches,  lamp  holders,  distribution 
fuse-boards,  ceiling  roses,  brackets,  pendants,  fans  and 
all  other  fittings  shall  be  so  chosen  that  they  are  of  the 
same  type  and  interchangeable  in  each  installation. 

7.11  Equipment 

Electrical  equipment  which  form  integral  part  of  wiring 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


59 


J 

25  min. 

1&0 
- r- 

31 

~lt<8 

12 


4B  SLAB  WITH  BEAM 

All  dimensions  in  millimetres. 

NOTES 

1  RCC  slab  steel  reinforcement  not  shown. 

2  Fan  clamp  shall  be  placed  in  position  such  that  its  projecting  arms  are  in  the  line  of  length  of  beam. 

Fig.  4  Typical  Design  of  Fan  Clamps 


60 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


intended  for  switching  or  control  or  protection  of  wiring 
installations  shall  conform  to  the  relevant  Indian 
Standards,  wherever  they  exist. 

7.12  Positioning  of  fans  and  light  fittings  shall  be 
chosen  to  make  these  effective  without  causing  shadows 
and  stroboscopic  effect  on  the  working  planes. 

8  F  ARTHING 

8.1  General 

8.1.1  Earthing  is  an  essential  part  of  any  electrical 
installation,  essential  for  the  safety  from  electrical 
shock,  and  fire  and  for  operation  of  most  of  the 
protective  systems  of  the  electrical  installation.  The 
earthing  provides  the  necessary  reference  of  zero 
potential  and  helps  in  activating  the  operation  of  the 
circuit  breaker  provided  for  the  safe  disconnection  of 
power  in  the  event  of  an  abnormality  in  the  flow  of 
current.  Earthing  systems,  apart  from  addressing  safety 
from  shock  and  fire,  help  in  limiting  the  interference 
between  one  appliance  and  the  other.  This  is  of 
particular  importance  in  the  case  of  voice  and  data 
communication  devices.  With  the  proliferation  in 
electrical/electronic  gadgets  and  greater  dependence 
on  voice  and  data  communication  systems,  proper  and 
effective  earthing  or  grounding  is  very  important. 
Earthing  is  also  necessary  for  diverting  the  effects  of 
lightning  strikes  from  the  buildings  and  its  contents, 
including  from  sensitive  equipment. 

8.1.2  Different  types  of  earth  electrodes  and  different 
types  of  earthing  systems  available.  For  low  voltage  and 
medium  voltage  systems  which  apply  to  almost  all 
electrical  systems  of  buildings,  the  common  earthing 
system  followed  is  with  the  neutral  solidly  earthed  at  the 
source.  This  system  requires  that  there  is  always  a 
protective  earth  continuity  conductor  running  all  through 
the  system  and  all  metal  parts  of  electrical  appliances 
connected  to  an  electrical  system  are  connected  to  the 
earth  continuity  conductor.  The  exception  to  this  system 
is  the  double  insulated  appliances  which  are  connected 
to  the  line  and  neutral  and  operate  on  low  voltage  (single 
phase)  and  are  also  of  low  power  consumption.  All 
appliances  (other  than  double  insulated  devices)  use  the 
earthing  through  the  earth  continuity  conductor.  Single 
phase  appliances  use  a  3-wire  connection  with  line  (live 
wire),  neutral  (return  path  wire)  and  the  earth-wire  at 
zero  potential.  Three  phase  appliances  use  a  connection 
with  4-wires  for  a  load  which  does  not  require  a  neutral 
connection  or  use  a  5-wire  connection  if  the  appliance 
requires  a  neutral  connection.  Care  should  be  taken  to 
ensure  that  the  earthing  system,  the  earth  continuity 
conductor  and  in  case  of  sockets  plugs  the  earthing  pin 
are  not  disconnected. 

8.1.3  Different  earthing  systems  have  features  which 
are  suitable  for  different  applications.  Earthing  system 


adopted  should  be  so  selected  so  as  to  match  with  the 
type  of  load,  protection  device,  application,  degree  of 
reliability,  etc.  For  classification  of  electrical  systems 
based  on  the  relationship  of  the  source,  and  of  exposed- 
conductive  parts  of  the  installation,  to  earth,  see  2.1.75. 

8.2  Selection  and  Design  of  Earthing  System 

8.2.1  Earthing  shall  generally  be  carried  out  in 
accordance  with  the  requirements  of  Regulation  16,  41 
and  48  of  Central  Electricity  Authority  (Measures 
relating  to  Safety  and  Electricity  Supply)  Regulations, 
20 1 0  as  amended  from  time-to-time  ( see  Annex  B)  and 
good  practice  [8-2(44)]  and  the  relevant  regulations  of 
the  Electricity  Supply  Authority  concerned. 

8.2.2  Conductors  and  earth  electrodes  in  an  earthing 
system  shall  be  so  designed  and  constructed  that  in 
normal  use  their  performance  is  reliable  and  without 
danger  to  persons  and  surrounding  equipment.  Earthing 
system  shall  be  designed  such  as  to  have  touch  potential 
and  step  potential  as  specified  in  good  practice 
[8-2(44)].  The  choice  of  a  material  depends  on  its  ability 
to  match  the  particular  application  requirement.  The 
requirements  for  earthing  arrangements  are  intended 
to  provide  a  connection  to  earth  which, 

a)  is  reliable  and  suitable  for  the  protective 
requirements  of  the  installation; 

b)  can  carry  earth  fault  currents  and  protective 
conductor  currents  to  earth  without  danger 
from  thermal,  thermo-mechanical  and 
electromechanical  stresses  and  from  electric 
shock  arising  from  these  currents; 

c)  if  relevant,  is  also  suitable  for  functional 
requirements;  and 

d)  is  suitable  for  the  foreseeable  external 
influences  {see  good  practice  [8-2(44)]  and 
IEC  60364-5-51:2005  ‘Electrical  installations 
of  buildings  —  Part  5-51:  Selection  and 
erection  of  electrical  equipment  —  Common 
rules’},  for  example,  mechanical  stresses  and 
corrosion. 

8.2.3  The  main  earthing  system  of  an  electrical 
installation  shall  consist  of, 

a)  an  earth  electrode,  (electrode  can  be  one 
vertical  rod/pipe/buried  plate  or  an  earth  mat 
with  several  vertical  installations  or  a  ring 
earthing  with  vertical  installations. 

b)  a  main  earthing  wire; 

c)  an  earth  bar  (located  on  the  main  switchboard 
for  small  installation  and  installed  in  the  wall/ 
room  in  case  of  large  industrial  electronic 
installations)  for  the  connection  of  the  main 
earthing  wire,  protective  earthing  wires  and / 
or  bonding  wires  within  the  installation;  and 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


61 


d)  a  removable  link,  which  effectively 
disconnects  the  neutral  bar  from  the  earth  bar. 
NOTE  —  The  requirements  of  (c)  and  (d)  shall  be  carried  out 
by  a  licensed  electrician  as  part  of  the  switchboard  installation. 

8.2.4  The  main  earthing  wire  connection  shall, 

a)  be  mechanically  and  electrically  sound; 

b)  be  protected  against  damage,  corrosion,  and 
vibration; 

c)  not  place  any  strain  on  various  parts  of  the 
connection; 

d)  not  damage  the  wire  or  fittings;  and 

e)  be  secured  at  the  earth  electrode. 

8.2.4. 1  The  main  earthing  wire  termination  shall  be 
readily  accessible  at  the  earth  electrode  except 
for  8.2.20.  As  far  as  possible,  all  earth  connections, 
except  exothermically  welded,  shall  be  visible  for 
inspection. 

8.2.5  Consideration  shall  be  given  to  the  earthing 
arrangements  where  currents  with  high  frequencies  are 
expected  to  flow  (see  444  of  IEC  60364-4-44:2007 
‘Low-voltage  electrical  installations  —  Part  4-44: 
Protection  for  safety  —  Protection  against  voltage 
disturbances  and  electromagnetic  disturbances’). 

8.2.6  Protection  against  electric  shock  (see  IEC  60364- 
4-41  ‘Low- voltage  electrical  installations  —  Part  4- 
41 :  Protection  for  safety  —  Protection  against  electric 
shock’),  shall  not  be  adversely  affected  by  any 
foreseeable  change  of  the  earth  electrode  resistance  (for 
example,  due  to  corrosion,  drying  or  freezing). 

8.2.7  Where  the  supply  to  an  installation  is  at  high  or 
extra  high  voltage,  requirements  concerning  the 
earthing  arrangements  of  the  high  or  extra  high  voltage 
supply  and  of  the  low-voltage  installation  shall  also 
comply  with  442  of  IEC  60364-4-44:2007  ‘Low- 
voltage  electrical  installations  —  Part  4-44:  Protection 
for  safety  —  Protection  against  voltage  disturbances 
and  electromagnetic  disturbances’. 

8.2.8  A  permanent  fitting  (like  a  screwed-down  plastic 
label  or  copper  label,  or  one  that  can  be  threaded  onto 
the  cable)  shall  be  used  at  the  connection  point  that  is 
clearly  marked  with  the  words:  ‘EARTHING  LEAD 
—  DO  NOT  DISCONNECT’  or  ‘EARTHING 
CONDUCTOR  —  DO  NOT  DISCONNECT’. 

8.2.9  All  medium  voltage  equipment  shall  be  earthed 
by  two  separate  and  distinct  connections  with  earth. 
The  contact  area  of  earth  conductor/plate  shall  be 
determined  in  accordance  with  good  practice 
[8-2(44)]. 

8.2.9.1  The  415/240  V,  4-wire,  3-phase  systems  are 
normally  operated  with  the  neutral  solidly  earthed  at 
source.  At  medium  voltage,  Central  Electricity 


Authority  regulations  require  that  the  neutral  be  earthed 
by  two  separate  and  distinct  connections  with  earth. 
Source  in  the  case  of  a  substation  (such  as  11  kV/415  V) 
will  be  the  neutral(s)  of  the  transformer(s).  Neutral 
conductor  shall  be  of  the  same  size  as  the  phase 
conductor. 

NOTE  —  Neutral  conductor  of  half  the  size  of  the  phase 
conductor  was  permitted  in  earlier  installations.  But  with  the 
proliferation  of  equipment  using  non-linear  devices  and 
consequent  increase  in  harmonics,  the  neutral  will  carry  a 
current  more  than  the  notional  out-of-balance  current  and 
therefore  neutral  conductor  shall  be  of  the  same  size  as  the 
phase  conductor. 

8.2.10  In  the  case  of  high  and  extra  high  voltages,  the 
neutral  points  shall  be  earthed  by  not  less  than  two 
separate  and  distinct  connections  to  earth,  each  having 
its  own  electrode  at  the  generating  station  or  substation 
and  may  be  earthed  at  any  other  point  provided  no 
interference  is  caused  by  such  earthing.  The  neutral 
may  be  earthed  through  suitable  impedance.  Neutral 
earthing  conductor  shall  be  sized  as  to  have  a  current 
carrying  capacity  not  less  than  the  phase  current. 

8.2.11  For  industrial/commercial  installations  having 
a  transformer  within  the  facility,  soil  resistivity  of  the 
place  of  installation  shall  be  measured  as  per  good 
practice  [8-2(44)]  and  recorded.  For  the  adopted  type 
of  earth  electrode  configuration,  earth  resistance  of  each 
electrode  configuration  shall  be  calculated  and  recorded 
based  on  good  practice  [8-2(44)]. 

8.2.12  It  is  recommended  that  a  drawing  showing  the 
main  earth  connection  and  earth  electrodes  be  prepared 
for  each  installation. 

8.2.13  Conductors,  other  than  live  conductors,  and  any 
other  parts  intended  to  carry  a  fault  current  shall  be 
capable  of  carrying  that  current  without  attaining  an 
excessive  temperature. 

8.2.14  Earth  system  shall  be  so  devised  that  the  testing 
of  individual  earth  electrode  is  possible  {except  for 
installations  according  to  5.3.6  of  good  practice 
[8-2(45)] } .  It  is  recommended  that  the  value  of  any  earth 
system  resistance  shall  be  such  as  to  conform  to  the 
degree  of  shock  protection  desired.  For  measuring 
purposes,  the  joint  shall  be  capable  of  being  opened  with 
the  aid  of  a  tool.  In  nonnal  use  it  shall  remain  closed. 

8.2.15  No  addition  to  the  current-carrying  system,  either 
temporary  or  permanent,  shall  be  made  which  will 
increase  the  maximum  available  earth  fault  current  or 
its  duration  until  it  has  been  ascertained  that  the  existing 
arrangement  of  earth  electrodes,  earth  bus-bar,  etc,  are 
capable  of  carrying  the  new  value  of  earth  fault  current 
which  may  be  obtained  by  this  addition. 

8.2.16  No  cut-out,  link  or  switch  other  than  a  linked 
switch  arranged  to  operate  simultaneously  on  the 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


earthed  or  earthed  neutral  conductor  and  the  live 
conductors,  shall  be  inserted  on  any  supply  system. 
This,  however,  does  not  include  the  case  of  a  switch 
for  use  in  controlling  a  generator  or  a  transformer  or  a 
link  for  test  purposes. 

8.2.17  All  materials,  fittings,  etc,  used  in  earthing  shall 
conform  to  relevant  Indian  Standard  specification, 
wherever  these  exist. 

8.2.18  Earthing  associated  with  current-carrying 
conductor  is  normally  essential  for  the  function  of  the 
system  and  is  generally  known  as  system  earthing  or 
functional  earthing,  while  earthing  of  non-current 
carrying  metal  work  and  conductor  is  essential  for  the 
safety  of  human  life,  of  animals  and  of  property  and  it 
is  generally  known  as  equipment  earthing  or  protective 
earthing.  The  earthing  arrangements  may  be  usedjointly 
or  separately  for  protective  and  functional  purposes 
according  to  the  requirements  of  the  electrical 
installation.  The  requirements  for  protective  purposes 
shall  always  take  precedence. 

8.2.19  For  selection  of  electrodes  for  use  in  corrosive 
environments,  reference  shall  be  made  to  good  practice 
[8-2(44)]. 

8.2.20  Test  joints  are  not  required  in  the  case  of  natural 
down-conductors  combined  with  foundation  earth 
electrodes  ( see  Fig.  5). 

8.2.21  For  computer  and  other  sensitive  electronic 
equipment  system  in  industrial  and  commercial 
application,  special  bonding  techniques  with  isolation 
transformer  should  be  employed  ( see  Fig.  6). 

8.2.22  Isolated  earthing  is  unsafe  during  a  transient 
condition.  In  unavoidable  conditions  if  isolated  earthing 
is  used,  to  reduce  potential  difference  between  isolated 
earthing,  earth  couplers  or  isolating  spark  gaps  shall 
be  installed.  This  will  reduce  potential  difference  during 
a  transient  condition  such  as  lightning. 

8.3  Earth  Electrodes 

The  efficacy  of  any  earth  electrode  depends  on  its 
configuration  and  upon  local  soil  conditions.  Number 
of  earth  electrodes  suitable  for  the  soil  conditions  and 
the  value  of  resistance  to  earth  required  shall  be 
considered.  Examples  of  earth  electrodes  which  may 
be  used  are, 

a)  concrete-embedded  foundation  earth 
electrode; 

b)  soil-embedded  foundation  earth  electrode; 

c)  metallic  electrode  embedded  directly  in  soil 
vertically  or  horizontally  (for  example  rods, 
wires,  tapes,  pipes  or  plates); 

d)  metal  sheath  and  other  metal  coverings  of 
cables  according  to  local  conditions  or 


requirements; 

e)  other  suitable  underground  metalwork  (for 
example,  pipes)  according  to  local  conditions 
or  requirements;  and 

f)  welded  metal  reinforcement  of  concrete 
(except  pre-stressed  concrete)  embedded  in 
the  earth. 

The  type,  materials  and  dimensions  of  earth  electrodes 
shall  be  selected  to  withstand  corrosion  and  to  have 
adequate  mechanical  strength  for  the  intended  lifetime. 
For  materials  commonly  used  for  earth  electrodes,  the 
minimum  sizes,  from  the  point  of  view  of  corrosion 
and  mechanical  strength,  when  embedded  in  the  soil 
or  in  concrete,  may  be  as  specified  in  Table  3.  If  a 
lightning  protection  system  is  required,  1 1 .5.3  applies 
{see  5.4  of  good  practice  [8-2(45)]}. 

NOTES 

1  For  corrosion,  the  parameters  to  be  considered  are:  the  soil 
pH  at  the  site,  soil  resistivity,  soil  moisture,  stray  and  leakage 
a.c.  and  d.c.  current,  chemical  contamination,  and  proximity 
of  dissimilar  materials. 

2  The  minimum  thickness  of  protective  coating  is  greater  for 
vertical  earth  electrodes  than  for  horizontal  earth  electrodes 
because  of  their  greater  exposure  to  mechanical  stresses  while 
being  embedded. 

Earth  electrode  either  in  the  form  of  solid  rod,  pipe, 
plate  or  earth  grid  should  be  provided  at  all  premises 
for  providing  an  earth  system.  Details  of  typical  pipe, 
rod  and  plate  earth  electrodes  are  given  in  Fig.  7  and 
Fig.  8.  Other  electrode  configurations  can  be  as  in  Fig.  9 
{see  also  9.2  of  good  practice  [8-2(44)]}. 

Although  electrode  material  does  not  affect  initial  earth 
resistance,  care  should  be  taken  to  select  a  material 
which  is  resistant  to  corrosion  in  the  type  of  soil  in 
which  it  is  used.  In  case  where  soil  condition  leads  to 
excessive  corrosion  of  the  electrode,  and  the 
connections,  it  is  recommended  to  use  either  copper/ 
stainless  steel  or  copper  coated  steel  electrode  and 
copper/stainless  steel  connections.  Exothermic  welding 
may  also  be  adopted  to  have  enhanced  life  and  strength 
to  the  connection  {see  Fig.  7B  and  Fig.  8B).  It  is 
recommended  to  use  similar  material  for  earth 
electrodes  and  earth  conductors  or  otherwise 
precautions  shoidd  be  taken  to  avoid  corrosion. 

8.4  Earth  Enhancing  Compound 

Multiple  rods,  even  in  large  numbers,  may  sometime 
fail  to  produce  an  adequately  low  resistance  to  earth. 
This  condition  arises  in  installations  involving  soils  of 
high  resistivity.  The  alternative  is  to  reduce  the 
resistivity  of  the  soil  immediately  surrounding  the  earth 
electrode.  To  reduce  the  soil  resistivity,  artificial  soil 
treatment  shall  be  adopted. 

8.4.1  Earthing  enhancing  compound  is  a  conductive 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


63 


NOTES 

1  Functional  earthing  conductors  are  not  shown  in  figure. 

2  Where  a  lightning  protection  system  is  installed,  the  additional  requirements 
are  given  in  11. 


Key 

C 

Extraneous-conductive-part 

Cl 

Water  pipe,  metal  from  outside 

C2 

Waste  water  pipe,  metal  from  outside 

C3 

Gas  pipe  with  insulating  insert,  metal 
from  outside 

C4 

Air  conditioning 

C5 

Heating  system 

C6 

Water  pipe,  metal  for  example  in  a 
bathroom 

C7 

Waste  water  pipe,  metal  for  example 
in  a  bathroom 

D 

Insulating  insert 

MDB 

Main  distribution  board 

DB 

Distribution  board 

MET 

Main  earthing  terminal 

SEBT 

Supplementary  equipotential  bonding 
terminal 

T1 

Concrete-embedded  foundation  earth 
electrode  or  soil-embedded  foundation 
earth  electrode 

T2 

Earth  electrode  for  LPS,  if  necessary 

LPS 

Lightning  protection  system  (if  any) 

PE 

PE  terminal(s)  in  the  distribution  board 

PE/PEN 

PE/PEN  terminal(s)  in  the  main 
distribution  board 

M 

Exposed-conductive-part 

1 

Protective  earthing  conductor  (PE) 

1 A 

Protective  conductor,  or  PEN  conductor, 
if  any,  from  supplying  network 

2 

Protective  bonding  conductor  for 
connection  to  the  main  earthing  terminal 

3 

Protective  bonding  conductor  for 
supplementary  bonding 

4 

Down  conductor  of  a  lightning  protection 
system  (LPS),  if  any 

5 

Earthing  conductor 

Fig.  5  Example  of  an  Earthing  Arrangement  for  Foundation  Earth  Electrode,  Protective 
Conductors  and  Protective  Bonding  Conductors 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


MAINS  SUPPLY 
3  PHASE  415  V 


Key 


Isolation  transformer 
Core 
Shield 

All  earthing  connections  made  at  a  point 
Connection  to  building  steel/earth 
pits/ring  earthing 
Conduit  earthing 
Neutral 

240/41 5  Volt  power  panel 
Neutral  bus11 

10  Earth  bus1’ 

1 1  Earth  connection  for  socket/work 
station/computers 

12  3-pin  sockets  with  isolated  earth  pin 

"  Both  busbars  isolated  from  panel 
enclosure.  No  bonding  connection 
between  neutral  and  earth. 

NOTES 

1  Each  branch  circuit  shall  have  a  separate  neutral 
and  earth  wire.  No  daisy  chaining  permitted. 

2  Only  computer  or  control  system  should  be  served 
from  this  panel. 


Fig.  6  Recommended  Power  Distribution  for  a  Computer  and  Control  System  with 
a  Delta/Star  Isolation  Transformer 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


65 


Table  3  Recommended  Minimum  Size  of  Commonly  Used  Earth  Electrodes,  Embedded  in  Soil  or 
Concrete  Used  to  Prevent  Corrosion  and  Provide  Mechanical  Strength1* 

(' Clause  8.3) 


SI 

Material  and 

Shape 

Diameter 

Cross- 

Thickness 

Weight  of 

Thickness  of 

No. 

Surface 

Sectional 

Coating 

Coating/ 

Area 

g/m2 

Sheathing 

mm 

mm2 

mm 

pm 

(1) 

(2) 

(3) 

(4) 

(5) 

(6) 

(7) 

(8) 

i) 

Steel  embedded  in 

Round  wire 

10 

_ 

_ 

_ 

_ 

concrete  (bare,  hot 
galvanized  or 
stainless) 

Solid  tape  or  strip 

75 

3 

ii) 

Steel  hot-dip 

Strip3)  or  shaped 

— 

90 

3 

500 

63 

galvanized2* 

strip/plate  —  solid 
plate  —  lattice  plate 
Round  rod  installed 

16 

350 

45 

vertically 

Round  wire  installed 

10 

350 

45 

horizontally 

Pipe 

25 

2 

350 

45 

Stranded 

— 

70 

— 

— 

— 

(embedded  in 
concrete) 

Cross  profile 
installed  vertically 

— 

(290) 

3 

— 

— 

iii) 

Steel  copper  sheathed 

Round  rod  installed 
vertically 

(15) 

2  000 

2506* 

iv) 

Steel  with  electro- 

Round  rod  installed 

14 

— 

— 

— 

deposited  copper 

vertically 

coating 

Round  wire  installed 

(8) 

— 

— 

— 

70 

Stainless  steel 4) 

horizontally 

Strip  installed 

horizontally 

— 

90 

3 

— 

70 

v) 

Strip3)  or  shaped 
strip/plate 

90 

3 

Round  rod  installed 

16 

— 

— 

— 

— 

vertically 

Round  wire  installed 

10 

horizontally 

Pipe 

25 

2 

vi) 

Copper 

Strip 

50 

2 

— 

— 

Round  wire  installed 

— 

(25)5>  50 

— 

— 

— 

horizontally 

Round  rod  installed 

(12)  15 

vertically 

Stranded  wire 

1.7  for 
individual 

(25)s>  50 

— 

— 

— 

strands  of  wire 

Pipe6’ 

20 

— 

2 

— 

— 

Solid  plate 

— 

— 

(1.5)2 

— 

— 

Lattice  plate 

— 

— 

2 

— 

— 

1  See  IEC  60364-5-54:201 1  ‘Low-voltage  electrical  installations  -  Part  5-54:  Selection  and  erection  of  electrical  equipment  -  Earthing 
arrangements  and  protective  conductors’. 

2)  The  coating  shall  be  smooth,  continuous  and  free  from  flux  stains. 

3)  As  rolled  strip  or  slit  strip  with  round  edges. 

4)  Chromium  >16  percent,  Nickel  >  5  percent,  Molybdenum  >  2  percent,  carbon  <  0.08  percent. 

5)  Where  experience  shows  that  the  risk  of  corrosion  and  mechanical  damage  is  extremely  low,  16  mm2  can  be  used. 

6)  This  thickness  is  provided  to  withstand  mechanical  damage  of  copper  coating  during  the  installation  process.  It  may  be  reduced  to  not 
less  than  100  pm  where  special  precautions  to  avoid  mechanical  damage  of  copper  during  the  installation  process  (for  example,  drilling 
holes  or  special  protective  tips)  are  taken  according  to  the  manufacturer’s  instruction. 

NOTES 

1  Values  in  bracket  are  applicable  for  protection  against  electric  shock  only,  while  values  not  in  brackets  are  applicable  for  lightning 
protection  and  for  protection  against  electric  shock. 

2  Metals  inserted  inside  pipe  will  not  influence  in  the  final  earth  resistance  value. 

3  Unprotected  ferrous  materials  are  not  recommended  due  to  high  corrosion  ( see  IEC  60364-4-43:2008  ‘Low-voltage  electrical 
installations  —  Part  4-43:  Protection  for  safety  -  Protection  against  overcurrent’). 


66 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


compound  producing  low  resistance  of  an  earth- 
termination  system.  These  compounds  used  for  artificial 
treatment  of  soil  {see  good  practice  [8-2  (44)]}  shall 
satisfy  the  requirements  as  per  IEC  62561-7:2011 
‘Lightning  protection  system  components  (LPSC)  — 
Part  7:  Requirements  for  earthing  enhancing 
compounds’. 

8.4.2  The  material  of  the  earthing  enhancing  compound 
shall  be  chemically  inert  to  subsoil.  It  shall  not  pollute 
the  environment.  It  shall  provide  a  stable  environment 
in  terms  of  physical  and  chemical  properties  and  exhibit 
low  resistivity.  The  earthing  enhancing  compound  shall 
not  be  corrosive  to  the  earth  electrodes  being  used. 

8.4.3  The  materials  used  for  artificial  treatment  should 
also  fulfil  toxicity  characteristic  leaching 
procedure  (TCLP)  requirements. 

8.4.4  Use  of  salt  [sodium  chloride  (NaCl)]  for  artificial 
treatment  of  soil  should  be  avoided  as  it  accelerates 
corrosion  of  ferrous  materials. 

8.5  Earth  Electrode  Inspection  Housings  and  Earth 
Electrode  Seals 

8.5.1  Earth  Electrode  Inspection  Housing 

Earth  electrode  inspection  housing  is  the  metallic  or 
non-metallic  enclosure  that  houses  the  down-conductor/ 
earth-termination  connection  for  inspection  and  testing 
purposes  and  consists  of  a  housing  and  a  removable 
lid.  The  design  of  the  earth  electrode  inspection  housing 
shall  be  such  that  it  carries  out  its  function  of  enclosing 
the  down-conductor/earth  rod  termination  in  an 
acceptable  and  safe  manner,  and  has  sufficient  internal 
dimensions  to  permit  the  assembly/disassembly  of  the 
earth  rod  clamp.  The  housing  body  shall  be  deep  enough 
to  permit  the  lid  to  sit  flush  on  the  body  without  fouling 
on  the  rod/conductor/clamp  assembly.  The  material  of 
the  earth  electrode  inspection  housing  shall  be 
compatible  with  its  surrounding  environment  and  shall 
comply  with  the  tests  given  in  IEC  62561-5:  2011 
‘Lightning  protection  system  components  (LPSC)  — 
Part  5:  Requirements  for  earth  electrode  inspection 
housings  and  earth  electrode  seals’. 

8.5.2  Earth  Electrode  Seed 

Water  pressure  seal  used  in  conjunction  with  an  earth 
rod  electrode  that  passes  through  the  foundation  of  the 
building.  The  design  of  the  earth  electrode  seal  shall 
be  such  that  it  carries  out  its  function  of  preventing 
ground  water  bypassing  the  earth  rod  and  entering  the 
basement  of  a  building,  in  an  acceptable  and  safe 
manner.  The  material  of  the  earth  electrode  seal  shall 
be  compatible  with  its  surrounding  environment  and 
comply  with  the  tests  given  in  IEC  62561-5:  2011 
‘Lightning  protection  system  components  (LPSC)  — 
Part  5:  Requirements  for  earth  electrode  inspection 
housings  and  earth  electrode  seals’. 


8.6  Bonding  and  Inter  connection 

All  connections  made  in  an  earthing  system  above  or 
below  ground  should  meet  electrical  conductivity, 
corrosion  resistance,  current  carrying  capacity,  and 
mechanical  strength  of  the  conductor.  These 
connections  should  be  strong  enough  to  maintain  a 
temperature  rise  below  that  of  the  conductor  and  to 
withstand  the  effect  of  heating  and  the  mechanical 
forces  caused  by  fault  currents.  Consideration  shall  be 
given  to  electrolytic  corrosion  when  using  different 
materials  in  an  earthing  arrangement.  The  complete 
connections  shall  be  able  to  resist  corrosion  for  the 
intended  life  of  the  installation 

8.6.1  For  external  conductors  (for  example  earthing 
conductor)  connected  to  a  concrete-embedded 
foundation  earth  electrode,  the  connection  made  from 
hot-dip  galvanized  steel  shall  not  be  embedded  in  the 
soil 

8.6.2  Where  an  earth  electrode  consists  of  parts  that 
must  be  connected  together,  the  connection  shall  be  by 
exothermic  welding,  pressure  connectors,  clamps  or 
other  suitable  mechanical  connectors. 

8.6.3  All  connection  components  shall  meet  the 
requirements  according  to  IEC  62561-1:2012 
‘Lightning  protection  system  components  (LPSC)  — 
Part  1:  Requirements  for  connection  components’. 

8.7  Equipment  and  Portions  of  Installations  which 
shall  be  Earthed 

8.7.1  Equipment  to  be  Earthed 

Except  for  equipment  provided  with  double  insulation, 
all  the  non-current  carrying  metal  parts  of  electrical 
installations  are  to  be  earthed  properly.  All  metal 
conduits,  trunking,  cable  sheaths,  switchgear, 
distribution  fuse  boards,  lighting  fittings  and  all  other 
parts  made  of  metal  shall  be  bonded  together  and 
connected  by  means  of  two  separate  and  distinct 
conductors  to  an  efficient  earth  electrode. 

8.7.2  Structural  Metal  Work 

Earthing  of  metallic  parts  of  the  structure  shall  be  done 
according  to  good  practices  [8-2(44)]  and  [8-2(45)]. 

8.8  Neutral  Earthing 

To  comply  with  relevant  Central  Electricity  Authority 
regulations,  no  fuses  or  circuit  breakers  other  than  a 
linked  circuit  breaker  shall  inserted  in  an  earthed  neutral 
conductor,  a  linked  switch  or  linked  circuit  breaker  shall 
be  arranged  to  break  or  the  neutral  either  with  or  after 
breaking  all  the  related  phase  conductors  and.  Shall 
positively  make  (or  close)  the  neutral  before  making 
(or  closing)  the  phases. 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


67 


1  a)  Cl  pipe  100  mm  ID  (Mm),  13  mm  thick  (Min) 
b)  Gl  pipe  (class  B)/MS  Rod,  40  mm  ID  (Min) 

2  Earth  enhancement  material  [confirming  to  IEC  62561-7:2011  ‘Lightning  protection  system  components  (LPSC)  — 
Part  7:  Requirements  for  earthing  enhancing  compounds'], 

or  sand,  salt  and  charcoal 

3  Inspection  chamber 

4  Universal  stainless  steel  clamp, 
or  50  x  3  mm  Gl  strip 

5  Ml 0  bolts  and  nuts 

6  Funnel  (for  maintenance/watering) 

7  Cl  lid/cover 

8  50  x  6  mm  Gl  strip 

All  dimensions  in  millimetres. 


NOTE  —  Inspection  housing  can  also  be  of  FRP  materials  with  Cl  cover  tested  according  to  IEC  6256 1  -5:201 1  ‘Lightning  protection 
system  components  (LPSC)  —  Part  5:  Requirements  for  earth  electrode  inspection  housings  and  earth  electrode  seals’. 

7 A  TYPICAL  ARRANGEMENT  OF  EARTHING  WITH  PIPE  ELECTRODE 
(WITH  MAINTENANCE  ARRANGEMENT) 

Fig.  7  —  ( Continued) 


68 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


•3  000 - -I- - 1  250 


—  25 

J 

—50  — 

L 1 

- - 7 

b 

5 - 

k 

u 

-1-,  f4 

— rrrn — rr~n — rrpn~^ 

^TXjxi — rrj~n — rrj-rr 

i 


DETAIL  A 


1 


Key 

1  Copper/copper  bonded  steel  rod  (see  Table  3  for  sizes) 

2  Earth  enhancement  material  [conforming  to  IEC  62561-7:2011  'Lightning  protection  system  components  (LPSC)  — 
Part  7:  Requirements  for  earthing  enhancing  compounds’] 

3  Inspection  chamber 

4  Ml 0  bolts  and  nuts 

5  Copper  strip  —  25  x  6  mm  or  higher 

6  Exothermic  welding 

7  Cl  lid/cover 

All  dimensions  in  millimetres. 

NOTE  —  Inspection  housing  can  also  be  of  FRP  materials  with  Cl  cover  tested  according  to  IEC  62561-5:2011  ‘Lightning  protection 
system  components  (LPSC)  —  Part  5:  Requirements  for  earth  electrode  inspection  housings  and  earth  electrode  seals’. 

7B  TYPICAL  ARRANGEMENT  OF  EARTHING  WITH  COPPER/COPPER  BONDED  ELECTRODE  WITH 
EXOTHERMIC  WELDING  (MAINTENANCE  FREE  ARRANGEMENT) 

Fig.  7  Typical  Arrangement  of  Electrode  Earthing 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


69 


3  000 - -I- - 1  250- 


11 


8 


Key 


50- 

ri 

ri 

n 

rr 

U 

- 800 - 

— - 100 - *-+ 

75  - 

u 

r 

ri 

ri 

-50 

— 

— 

— 

— cc 

V 

CD - 

— 

10- 

/ 

— 

DETAIL  B 


1  50  mm  dia  Gl  pipe  for  watering  (maintenance) 

2  a)  35  x  6  mm  copper  strip 
b)  50  x  12  mm  Gl  Strip 

3  Inspection  chamber 

4  Funnel  (for  watering/maintenance) 

5  Earth  enhancement  material  [conforming  to  IEC  62561-7:2011  ‘Lightning  protection  system  components  (LPSC)  — 
Part  7:  Requirements  for  earthing  enhancing  compounds’], 


or 

sand,  salt  and  charcoal 

6 

a) 

600  x  600  x  3  mm  copper  plate 

b) 

600  x  600  x  6  mm  Gl  plate 

c) 

1  200  x  1  200  x  12  mm  Cl  plate 

7 

a) 

Ml 2  x  40  brass  bolts  and  nuts 

b) 

M12  x  60  Gl  bolts  and  nuts 

8 

a) 

M10  x  30  brass  bolts  and  nuts 

b) 

Ml 2  x  50  Gl  bolts  and  nuts 

9 

a) 

Ml 2  x  40  brass  bolts  and  nuts 

b) 

M12  x  60  Gl  bolts  and  nuts 

10 

a) 

35  x  6  copper  strip 

b) 

50  x  12  mm  Gl  strip 

11 

Cl 

lid/cover 

12 

a) 

25  x  4  mm  copper  strip  for  clamp 

b) 

50  x  12  mm  Gl  copper  strip  for  clamp 

All  dimensions  in  millimetres. 

NOTE  —  Inspection  housing  can  also  be  of  FRP  materials  with  Cl  cover,  tested  according  to  IEC  62561-5:  2011  ‘Lightning 
protection  system  components  (LPSC)  —  Part  5:  Requirements  for  earth  electrode  inspection  housings  and  earth  electrode  seals’. 


8A  TYPICAL  ARRANGEMENT  OF  CI/GI/COPPER  PLATE  EARTHING  (WITH  MAINTENANCE  ARRANGEMENT) 

Fig.  8  —  ( Continued ) 


70 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


8 


DETAIL  A 


(L  itL 

-□411  rrjii 

1  I  I  I  I  Mill 


■800- 


'L&.  JUl 


DETAIL  B 


3  V6 


Key 

1  600  x  600  x  3  mm  copper  plate 

2  30  x  6  mm  copper  strip 

3  Exothermic  welding 

4  Earth  enhancement  material  [conforming  to  IEC  62561-7:2011  ‘Lightning  protection  system  components  (LPSC)  — 
Part  7:  Requirements  for  earthing  enhancing  compounds'] 

5  Inspection  chamber 

6  Ml 2  x  40  stainless  steel  bolts  and  nuts 

7  50  x  6  mm  copper  strip 

8  Cl  lid/cover 

All  dimensions  in  millimetres. 

NOTE  —  Inspection  housing  can  also  be  of  FRP  materials  with  Cl  cover  tested  according  to  IEC  6256 1  -5:201 1  ‘Lightning  protection 
system  components  (LPSC)  —  Part  5:  Requirements  for  earth  electrode  inspection  housings  and  earth  electrode  seals’. 


8B  TYPICAL  ARRANGEMENT  OF  COPPER  PLATE  EARTHING  WITH  EXOTHERMIC  WELDING 
(MAINTENANCE  FREE  ARRANGEMENT) 

Fig.  8  Typical  Arrangement  of  Plate  Earthing 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


71 


1 

A 

Three  rods  at  the  vertices  of  an 
equilateral  triangle 

2 

Two  strips  set  at  right  angles  to  each 
other,  meeting  at  one  corner 

3 

Vertical  electrodes  interconnected  as 
a  square 

4 

Three  strips  set  at  120°,  meeting  at  the 
star  point,  all  of  equal  length 

5 

Four  strips  set  in  a  cruciform 

6 

"1 

A 

Ai 

Vertical  rod 

1  Extensible  earth  rod 

2  Rod  coupling 

3  Soil 

4  Conductor  to  rod  clamp 

5  Earthing  conductor 

Fig.  9  Miscellaneous  Electrode  Configurations 


If  this  neutral  point  of  the  supply  system  is  connected 
permanently  to  earth,  then  the  above  rule  applies 
throughout  the  installation  including  2-wire  final 
circuits.  This  means  that  no  fuses  may  be  inserted  in 
the  neutral  or  common  return  wire.  And  the  neutral 
should  consist  of  a  bolted  solid  link,  or  part  of  a  linked 
switch,  which  completely  disconnects  the  whole  system 
from  the  supply.  This  linked  switch  shall  be  so  arranged 
that  the  neutral  makes  before,  and  break  after  the 
phases. 

8.9  System  of  Earthing 

Equipment  and  portions  of  installations  shall  be  deemed 
to  be  earthed  only  if  earthed  in  accordance  with  either 
the  direct  earthing  system,  the  multiple  earthed  neutral 
system  or  the  earth  leakage  circuit-breaker  system.  In 
all  cases,  the  relevant  provisions  of  Central  Electricity 


Authority  regulation  shall  be  complied  with. 

8.10  The  earthing  of  electrical  installations  for  non¬ 
industrial  and  industrial  buildings  shall  be  done  in 
accordance  with  good  practice  [8-2(44)]. 

9  INSPECTION,  TESTING  AND  VERIFICATION 
OF  INSTALLATION 

9.1  General  Requirements 

9.1.1  Before  the  completed  installation,  or  an  addition 
to  the  existing  installation,  is  put  into  service,  inspection 
and  testing  shall  be  carried  out  in  accordance  with  the 
Central  Electricity  Authority  (Measures  Relating  to 
Safety  and  Electric  Supply)  Regulations,  2010,  as 
amended  from  time-to-time.  In  this  connection, 
Regulation  4,  5,  5A,  8,  30,  31,  32,  40  and  46  of  the 


72 


NATIONAL  BUILDING  CODE  OF  INDIA  2016 


regulation  shall  be  complied  with  (see  Annex  B).  In 
the  event  of  defects  being  found,  these  shall  be  rectified, 
as  soon  as  practicable  and  the  installation  retested. 

9.1.2  Periodic  inspection  and  testing  shall  be  carried 
out  in  order  to  maintain  the  installation  in  a  sound 
condition  after  putting  into  service. 

9.1.3  Where  an  addition  is  to  be  made  to  the  fixed  wiring 
of  an  existing  installation,  the  latter  shall  be  examined 
for  compliance  with  the  recommendations  of  the  Code. 

9.1.4  The  individual  equipment  and  materials  which 
form  part  of  the  installation  shall  generally  conform  to 
the  relevant  Indian  Standard  specification,  wherever 
applicable.  If  there  is  no  relevant  Indian  Standard 
specification  for  any  item,  these  shall  be  approved  by 
the  appropriate  authority. 

9.1.5  Completion  Drawings 

On  completion  of  the  electric  work,  a  wiring  diagram 
shall  be  prepared  and  submitted  to  the  Engineer-in- 
Charge  or  the  owner.  All  wiring  diagrams  shall  indicate 
clearly,  the  main  switch  board,  the  runs  of  various  mains 
and  submains  and  the  position  of  all  points  and  their 
controls.  All  circuits  shall  be  clearly  indicated  and 
numbered  in  the  wiring  diagram  and  all  points  shall  be 
given  the  same  number  as  the  circuit  in  which  they  are 
electrically  connected.  Also  the  location  and  number 
of  earth  points  and  the  run  of  each  loads  should  be 
clearly  shown  in  the  completion  drawings. 

9.2  Inspection  of  the  Installation 

9.2.1  General 

On  completion  of  wiring  a  general  inspection  shall  be 
carried  out  by  competent  personnel  in  order  to  verify 
that  the  provisions  of  this  Code  and  that  of  Central 
Electricity  Authority  (Measures  Relating  to  Safety  and 
Electric  Supply)  Regulations,  2010,  have  been 
complied  with.  This,  among  other  things,  shall  include 
checking  whether  all  equipment,  fittings,  accessories, 
wires/cables,  used  in  the  installation  are  of  adequate 
rating  and  quality  to  meet  the  requirement  of  the  load. 
General  workmanship  of  the  electrical  wiring  with 
regard  to  the  layout  and  finish  shall  be  examined  for 
neatness  that  would  facilitate  easy  identification  of 
circuits  of  the  system,  adequacy  of  clearances, 
soundness,  contact  pressure  and  contact  area.  A 
complete  check  shall  also  be  made  of  all  the  protective 
devices,  with  respect  to  their  ratings,  range  of  settings 
and  coordination  between  the  various  protective 
devices. 

9.2.2  Item  to  be  Inspected 

All  equipment  in  a  substation  including  HV  panel, 
transformer,  LV  panel,  emergency  DG  sets,  battery 
bank,  cables,  cable  terminations,  etc,  need  inspection. 


Healthiness  of  the  main  distribution  boards,  metering 
panels,  distribution  cables,  rising  mains,  bus  ducts,  etc, 
need  to  be  verified  along  with  earthing  system. 

9.2.2. 1  Substation  installations 

In  substation  installation,  it  shall  be  checked  whether, 

1)  the  installation  has  been  carried  out  in 
accordance  with  the  approved  drawings; 

2)  phase  to  phase  and  phase  to  earth  clearances 
are  provided  as  required; 

3)  all  equipment  are  efficiently  earthed  and 
properly  connected  to  the  required  number  of 
earth  electrodes; 

4)  HV  and  MV/LV  switchgears  are  all  vermin 
and  damp-proof  and  all  unused  openings  or 
holes  are  blocked  properly; 

5 )  the  required  ground  clearance  to  live-tenninals 
is  provided; 

6)  suitable  fencing  is  provided  with  gate  with 
lockable  arrangements; 

7)  there  is  no  vegetation  in  outdoor  substation; 

8)  the  required  number  of  caution  boards,  fire¬ 
fighting  equipment,  operating  rods,  rubber 
mats,  etc,  are  kept  in  the  substation; 

9)  in  case  of  indoor  substation  sufficient 
ventilation  and  draining  arrangements  are 
made; 

10)  all  cable  trenches  are  provided  with  non- 
inflammable  covers; 

1 1 )  free  accessibility  is  provided  for  all  equipment 
for  normal  operation; 

12)  all  name  plates  are  fixed  and  the  equipment 
are  fully  painted; 

13)  all  construction  materials  and  temporary 
connections  are  removed; 

14)  oil-level,  bus  bar  tightness,  transformer  tap 
position,  etc,  are  in  order; 

15)  earth  pipe  troughs  and  cover  slabs  are 
provided  for  earth  electrodes/earth  pits  and 
the  neutral  and  lightning  arrestor  earth  pits  are 
marked  for  easy  identification; 

1 6)  earth  electrodes  are  of  GI  pipes  or  Cl  pipes  or 
copper  plates  or  Cu  bonded  rods  as  per 
Table  3.  For  earth  connections,  brass  bolts  and 
nuts  with  lead  washers  are  provided  in  the 
pipes/plates; 

1 7)  earth  pipe  troughs  and  oil  sumps/pits  are  free 
from  rubbish  and  dirt  and  stone  jelly  and  the 
earth  connections  are  visible  and  easily 
accessible; 

18)  earthing  system  designed  are  periodically 
checked  for  permissible  limits  of  step  and 
touch  potential. 


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73 


19)  the  earth  bus  bars  have  tight  connections  and 
corrosion-free  joint  surfaces; 

20)  operating  handle  of  protective  device  are 
provided  at  an  accessible  height  from  ground, 
that  is,  300  mm  to  1  800  mm; 

21)  adequate  headroom  is  available  in  the 
transformer  room  for  easy  topping-up  of  oil, 
maintenance,  etc; 

22)  safety  devices,  horizontal  and  vertical  barriers, 
bus  bar  covers/shrouds,  automatic  safety 
shutters/doors  interlock,  handle  interlock  are 
safe  and  in  reliable  operation  in  all  panels  and 
cubicles; 

23)  clearances  in  the  front,  rear  and  sides  of  the 
main  HV  and  MV  and  sub-switch  boards  are 
adequate; 

24)  the  switches  operate  freely;  the  3  blades  make 
contact  at  the  same  time,  the  arcing  horns 
contact  in  advance;  and  the  handles  are 
provided  with  locking  arrangements; 

25)  insulators  are  free  from  cracks,  and  are  clean; 

26)  in  transformers,  there  is  any  oil  leak; 

27)  connections  to  bushing  in  transformers  for 
tightness  and  good  contact; 

28)  bushings  are  free  from  cracks  and  are  clean; 

29)  accessories  of  transformers  like  breathers,  vent 
pipe,  buchholz  relay,  etc,  are  in  order; 

30)  connections  to  gas  relay  in  transformers  are 
in  order; 

31)  oil  and  winding  temperature  are  set  for  specific 
requirements  in  transformers; 

32)  in  case  of  cable  cellars,  adequate  arrangements 
to  pump  out  water  that  has  entered  due  to 
seepage  or  other  reasons; 

33)  all  incoming  and  outgoing  circuits  of  HV  and 
MV  panels  are  clearly  and  indelibly  labelled 
for  identifications; 

34)  no  cable  is  damaged; 

35)  there  is  adequate  clearance  around  the 
equipment  installed;  and 

36)  cable  terminations  are  proper. 

9.2.2. 2  Medium/low  voltage  installation 

In  medium  and  low  voltage  installations,  it  shall  be 
checked  whether, 

a)  all  blocking  materials  that  are  used  for  safe 
transportation  in  switchgears,  contactors, 
relays,  etc,  are  removed; 

b)  all  connections  to  the  earthing  system  are 
feasible  for  periodical  inspection; 

c)  sharp  cable  bends  are  avoided  and  cables  are 
taken  in  a  smooth  manner  in  the  trenches  or 


alongside  the  walls  and  ceilings  using  suitable 
support  clamps  at  regular  intervals; 

d)  suitable  circuit  breaker  or  lockable  push 
button  is  provided  near  the  motors/apparatus 
for  controlling  supply  to  the  motor/apparatus 
in  an  easily  accessible  location; 

e)  two  separate  and  distinct  earth  connections  are 
provided  for  the  motor/apparatus; 

f)  control  switch-fuse  is  provided  at  an 
accessible  height  from  ground  for  controlling 
supply  to  overhead  travelling  crane,  hoists, 
overhead  bus  bar  trunking; 

g)  the  metal  rails  on  which  the  crane  travels  are 
electrically  continuous  and  earthed  and 
bonding  of  rails  and  earthing  at  both  ends  are 
done; 

h)  four  core  cables  are  used  for  overhead 
travelling  crane  and  portable  equipment,  the 
fourth  core  being  used  for  earthing,  and 
separate  supply  for  lighting  circuit  is  taken; 

j)  if  flexible  metallic  hose  is  used  for  wiring  to 
motors  and  other  equipment,  the  wiring  is 
enclosed  to  the  full  lengths,  and  the  hose 
secured  properly  by  approved  means; 

k)  the  cables  are  not  taken  through  areas  where 
they  are  likely  to  be  damaged  or  chemically 
affected; 

m)  the  screens  and  armours  of  the  cables  are 
earthed  properly; 

n)  the  belts  of  the  belt  driven  equipment  are 
properly  guarded; 

p)  adequate  precautions  are  taken  to  ensure  that 
no  live  parts  are  so  exposed  as  to  cause  danger; 

q)  ammeters  and  voltmeters  are  tested; 

r)  the  relays  are  inspected  visually  by  moving 
covers  for  deposits  of  dusts  or  other  foreign 
matter; 

s)  wherever  bus  ducts/rising  mains/ overhead  bus 
trucking  are  used,  special  care  being  taken  for 
earthing  the  system.  All  tap  off  points  are 
provided  with  adequately  rated  protective 
device  like  MCB,  MCCB,  fuses,  RCCB/RCD, 
SPD  ( see  11),  etc; 

t)  all  equipment  are  weather,  dust  and  vermin 
proof;  and 

u)  any  and  all  equipment  having  air  insulation 
as  media  maintain  proper  distances  between 
phases;  phase  to  neutral;  phase  to  earth  and 
earth  to  neutral. 

9.2.2.3  Overhead  lines 

For  overhead  lines,  it  shall  be  checked  whether, 

a)  all  conductors  and  apparatus  including  live 


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parts  thereof  are  inaccessible; 

b)  the  types  and  size  of  supports  are  suitable  for 
the  overhead  lines/conductors  used  and  are  in 
accordance  with  approved  drawing  and 
standards; 

c)  clearances  from  ground  level  to  the  lowest 
conductor  of  overhead  lines,  sag  conditions, 
etc,  are  in  accordance  with  4.7; 

d)  where  overhead  lines  cross  the  roads  or  cross 
each  other  or  are  in  proximity  with  one 
another,  suitable  guarding  is  provided  at  road 
crossings  and  also  to  protect  against  possibility 
of  the  lines  coming  in  contact  with  one 
another; 

e)  every  guard  wire  is  properly  earthed; 

f)  the  type,  size  and  suitability  of  the  guarding 
arrangement  provided  is  adequate; 

g)  stays  are  provided  suitably  on  the  overhead 
lines  as  required  and  are  efficiently  earthed 
or  provided  with  suitably  stay  insulators  of 
suitable  voltages; 

h)  anti-climbing  devices  and  danger  board/ 
caution  board,  notices  are  provided  on  all  HV 
supports; 

j)  clearances  along  the  route  are  checked  and 
all  obstructions,  such  as,  trees/branches  and 
shrubs  are  cleared  on  the  route  to  the  required 
distance  on  either  side; 

k)  clearance  between  the  live  conductor  and  the 
earthed  metal  parts  are  adequate; 

m)  for  the  service  connections  tapped-off  from 
the  overhead  lines,  cut-outs  of  adequate 
capacity  are  provided; 

n)  all  insulators  are  properly  and  securely 
mounted;  also  they  are  not  damaged. 

p)  all  poles  are  properly  grouted/insulated  so  as 
to  avoid  bending  of  pole  towards  tension;  and 

q)  steel  poles,  if  used  is  properly  earthed. 

9.2.2.4  Lighting  and  convenience  power  circuits 

For  the  lighting  and  convenience  power  circuits,  it  shall 
be  checked  whether, 

a)  wooden  boxes  and  panels  are  avoided  in 
factories  for  mounting  the  lighting  boards  and 
switch  controls,  etc; 

b)  neutral  links  are  provided  in  double  pole 
switch-fuses  which  are  used  for  lighting 
control,  and  no  protective  device  (such  as 
MCB,  MCCB,  fuses,  RCCB/RCD,  etc)  is 
provided  in  the  neutral; 

c)  the  plug  points  (6  A)  in  the  lighting  circuit  are 
all  of  3/5-pin  type,  the  third  pin  being  suitably 
earthed; 


d)  the  plug  points  (16  A)  in  the  lighting  circuit 
are  all  of  3/6-pin  type,  the  third  pin  being 
suitably  earthed; 

e)  tamper-proof  interlocked  switch  socket  and 
plug  are  used  for  locations  easily  accessible; 

f)  lighting  wiring  in  factory  area  is  taken 
enclosed  in  conduit  and  conduit  properly 
earthed,  or  alternatively,  armoured  cable 
wiring  is  used; 

g)  a  separate  earth  wire  is  run  in  the  lighting 
installation  to  provide  earthing  for  plug  points, 
fixtures  and  equipment; 

h)  proper  connectors  and  junction  boxes  are  used 
wherever  joints  are  to  be  made  in  conductors 
or  cross-over  of  conductors  takes  place; 

j)  cartridge  fuse  units  are  fitted  with  cartridge 
fuses  only; 

k)  clear  and  permanent  identification  marks  are 
painted  in  all  distribution  boards, 
switchboards,  sub-main  boards  and  switches 
as  necessary; 

m)  the  polarity  has  been  checked  and  all 
protective  devices  (such  as  MCB,  MCCB, 
fuses,  RCCB/RCD,  etc)  and  single  pole 
switches  are  connected  on  the  phase  conductor 
only  and  wiring  is  correctly  connected  to 
socket-outlets; 

n)  spare  knockouts  provided  in  distribution 
boards  and  switch  fuses  are  blocked; 

p)  the  ends  of  conduits  enclosing  the  wiring  leads 
are  provided  with  ebonite  or  other  suitable 
bushes; 

q)  the  fittings  and  fixtures  used  for  outdoor  use 
are  all  of  weather-proof  construction  and  of 
suitable  IP  and  IK  rating,  and  similarly, 
fixtures,  fittings  and  switchgears  used  in  the 
hazardous  area,  are  of  flame-proof 
application; 

r)  proper  terminal  connectors  are  used  for 
termination  of  wires  (conductors  and  earth 
leads)  and  all  strands  are  inserted  in  the 
terminals; 

s)  flat  ended  screws  are  used  for  fixing  conductor 
to  the  accessories; 

t)  use  of  flat  washers  backed  up  by  spring 
washers  for  making  end  connections  is 
desirable;  and 

u)  all  metallic  parts  of  installation,  such  as 
conduits,  distribution  boards,  metal  boxes,  etc, 
have  been  properly  earthed. 

9.3  Testing  of  Installation 

9.3.1  General 

After  inspection,  the  following  tests  shall  be  carried 


PART  8  BUILDING  SERVICES  —  SECTION  2  ELECTRICAL  AND  ALLIED  INSTALLATIONS 


75 


out,  before  an  installation  or  an  addition  to  the  existing 
installation  is  put  into  service.  Any  testing  of  the 
electrical  installation  in  an  already  existing  installation 
shall  commence  after  obtaining  permit  to  work  from 
the  Engineer-in-Charge  and  after  ensuring  the  safety 
provisions. 

Testing  of  the  installations  will  cover  the  testing  of 
equipment,  connections,  cables,  switchgear,  protective 
devices,  circuit  breakers  and  the  associated  relays, 
measuring  instruments  and  earthing.  Periodicity  of 
testing  should  not  exceed  six  months.  More  frequent 
testing  may  be  prescribed  for  complex  installations  and 
installations  feeding  sensitive  loads.  Due  date  of  next 
test  cycle  should  be  displayed  on  the  equipment. 

9.3.2  Testing 

9.3.2. 1  Switchboards 

HV  and  MV  switchboards  shall  be  tested  in  the  manner 
indicated  below: 

a)  All  high  voltage  switchboards  shall  be  tested 
for  dielectric  test  as  per  good  practice 
[8-2(14)]. 

b)  All  earth  connections  shall  be  checked  for 
continuity. 

c)  The  operation  of  the  protective  devices  shall 
be  tested  by  means  of  secondary  or  primary 
injection  tests. 

d)  The  operation  of  the  breakers  shall  be  tested 
from  all  control  stations. 

e)  Indication/Signalling  lamps  shall  be  checked 
for  proper  working. 

f)  The  operation  of  the  breakers  shall  be  tested 
for  all  interlocks. 

g)  The  closing  and  opening  timings  of  the 
breakers  shall  be  tested,  wherever  required  for 
auto-transfer  schemes. 

h)  Contact  resistance  of  main  and  isolator 
contacts  shall  be  measured. 

j)  The  specific  gravity  and  the  voltage  of  the 
control  battery  shall  be  measured. 

9.3.2.2  Transformers 

Transformers  shall  be  tested  in  the  manner  indicated 
below: 

a)  All  commissioning  tests  shall  be  in  accordance 
with  good  practice  [8-2(9)]. 

b)  Insulation  resistance  on  HV  and  MV  windings 
shall  be  measured  at  the  end  of  1  min  as  also 
at  the  end  of  10  min  of  measuring  the 
polarization  index.  The  absolute  value  of 
insulation  resistance  should  not  be  the  sole 
criterion  for  determining  the  state  of  dryness 
of  the  insulation.  Polarization  index  values 


should  form  the  basis  for  determining  the  state 
of  dryness  of  insulation.  For  any  class  of 
insulation,  the  polarization  index  should  be 
greater  than  1.5. 

9.3. 2.3  Cables 

Cable  installations  shall  be  checked  as  given  below: 

a)  It  shall  be  ensured  that  the  cables  conform  to 
the  relevant  Indian  Standards.  Tests  shall  also 
be  done  in  accordance  with  good  practice 
[8-2(  11)]  and  [8-2(  15)].  The  insulation  resistance 
before  and  after  the  tests  shall  be  checked. 

b)  The  insulation  resistance  between  each 
conductor  and  against  earth  shall  be  measured. 
The  insulation  resistance  varies  with  the  type 
of  insulation  used  and  with  the  length  of  cable. 
The  following  empirical  rule  gives  reasonable 
guidance: 

Insulation  resistance  =  10xVoltage,  in  kV 

in  megaohms  Length,  in  km 

c)  Physical  examination  of  cables  shall  be  carried 
out. 

d)  Cable  terminations  shall  be  checked. 

e)  Continuity  test  shall  be  performed  before 
charging  the  cable  with  current. 

9.3.2.4  Motors  and  other  equipment 

The  following  tests  shall  be  made  on  motor  and  other 
equipment. 

The  insulation  resistance  of  each  phase  winding  against 
the  frame  and  between  the  windings  shall  be  measured. 
Megger  of  500  V  or  1  000  V  rating  shall  be  used.  Star 
points  should  be  disconnected.  Minimum  acceptable 
value  of  the  insulation  resistance  varies  with  the  rated 
power  and  the  rated  voltage  of  the  motor. 

The  following  relation  may  serve  as  a  reasonable  guide: 

20xE 

D  _ _ n 

1  1000  +  2P 

where 

=  insulation  resistance  in  mega-ohms  at  25°C. 

En  =  rated  phase  to  phase  voltage. 

P  =  rated  power,  in  kW. 

If  the  resistance  is  measured  at  a  temperature  different 
from  25°C,  the  value  shall  be  corrected  to  25°C. 

The  insulation  resistance  as  measured  at  ambient 
temperature  does  not  always  gives  a  reliable  value,  since 
moisture  may  have  been  absorbed  during  shipment  and 
storage.  When  the  temperature  of  such  a  motor  is  raised, 
the  insulation  resistance  will  initially  drop  considerably, 
even  below  the  acceptable  minimum.  If  any  suspicion 


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NATIONAL  BUILDING  CODE  OF  INDIA  2016 


exists  on  this  score,  motor  winding  shall  be  dried  out. 

9.3.2.5  Wiring  installation 

The  following  tests  shall  be  done: 

a)  The  insulation  resistance  shall  be  measured 
by  applying  between  earth  and  the  whole 
system  of  conductor  or  any  section  thereof 
with  all  fuses  in  place  and  all  switches  closed, 
and  except  in  earthed  concentric  wiring,  all 
lamps  in  position  or  both  poles  of  installation 
otherwise  electrically  connected  together,  a 
d.c.  voltage  of  not  less  than  twice  the  working 
voltage,  provided  that  it  does  not  exceed 
500  V  for  medium  voltage  circuits.  Where  the 
supply  is  derived  from  three-wire  (a.c.  or  d.c.) 
or  a  poly-phase