in any in any only in living except rooms and on walls, rooms (but not facade of the in rooms on the building and roof) and only ceilings of as a lining to staircases and solid walls and corridors partitions. Not on staircases or corridors or facade of the building
NOTE (lining) shall be permitted in a limited area. It shall not be permitted in a vestibule.
Materials of Class 4 which include untreated wood fibre-boards may be used as ceiling lining, provided the ceiling is at least 2.4 m from the top surface of the floor below, and the wall surfaces conform to requirements of [see Note under Class 4 materials shall not be used in kitchens, corridors and staircases. Some types contain bitumen and, in addition to risk from spread of fire, emit dense smoke on burning; such materials shall be excluded from use under these conditions and shall
also not be used for
construction of ceiling where the plenum is used for return air in air-conditioned buildings.6.15.5 When frames, walls, partitions or floors are
lined with combustible
materials, the surfaces on bothsides of the materials
NATIONAL BUILDING CODE OF INDIA
shall conform to the appropriate class, because there is considerable from fire starting and rapidly within the concealed cavity unknown to occupants whose escape may he hampered by. For detailed information on materials and details of construction with their fire-resistance rating, reference may be made to accepted standards [I V(4)].
6.16 Glazing
Building of Types to 4 construction shall employ one of the two types of glazing described in and 6.16.3 except that Type 4 construction may have the alternative of hardwood sashes or frames or both.
Wired glass shall comply with the following requirements:
THICKNESS OF- G L AS S-The thickness of glass shall be not less than 6.5 mm.
EMBEDDED N E T T I N G - E m b e d d e d wire netting shall be not largerthan 2.5 cm mesh.
SIZE OF SQUARES OF GLASS--The area shall not exceed 2
AND s a s h e s o r
frames or both shall be entirely of iron or other suitable metal securely bolted or keyed into the except in the case of panels in internal doors. . . SETTING OF GLASS-The panels of shall be set in rebates or grooves not less than 6.5 mm in width or depth, with due allowance for expansion, and shall be secured by hard metal fastenings to the sashes or frames independently of any lead, cement or putty used for weather-proofing purposes.
6.16.3 glazing shall comply with the following requirements:
Thickness of glass shall be not less than 6.5 mm.
Size of squares 100
of glass shall not exceed
SECTIONAL LIGHTS -The square glasses
to be formed by glazing
into sectional lights shall not exceed 0.37 in area.
SASHES AND FRAMES-The sashes or frames or both shall be entirely of iron or other hard metal, securely bolted or keyed into the wall, except when in panels in internal doors.
e) FIXING OF SECTIONAL LIGHTS-The sectional lights shall be set in rebate or
I V
grooves not less than 6.5 mm in width or depth, with due allowance for expansion and shall be secured by hard metal fastenings to the sashes or frames independently of any lead, cement or putty used for weather-proofing purposes.
6.16.4 No wall opening exceeding 5 shall be deemed capable of efficient protection by wired glass or electro-copper glazing.
CA S E M E N T- H a r d m e t a l c a s e m e n t s , not exceeding 0.8 fitted with wired glass or e l e c t r o - c o p p e r g l a z i n g i n a c c o r d a n c e with 6.16.2 and 6.16.3, secured to the frames by hard metal hinges not more than 60 cm apart and by fastenings at top, centre and bottom shall be permissible.
6.17 Skylights
Wired glass for skylights or monitor lights shall comply with the following requirements:
Thickness of glass shall be not less than 6.5 mm;
Embedded wire netting shall be not larger than 2.5 cm mesh;
F R A M E S AN D f r a m e shall be continuous and divided by bars spaced at not more than 70 cm The frame and bars shall be of iron or other hard metal, and supported on a curb either-of metal or of wood covered with sheet metal. The glass shall be secured by hard metal fastenings to the frame and bars independently of any lead, cement or putty used for weather-proofing purposes.
6.17.2 No skylight opening exceeding 5 shall be deemed capable ofefficient protection by wired glass.
6.18 fire Where applicable, fire lifts shall be provided with a. minimum capacity for 8 passengers and fully automated with emergency switch on ground level. In general, buildings over 15 m in height shall be provided with fire lifts [see
6.18.1 In case of fire, only fireman shall operate fire-lifts. In normal course, it may be used by other persons.
Each fire lift shall be equipped with suitable inter-communication equipment for communicating with the control room on the ground floor of the building.
6.18.3 The number and location of fire lifts in a building shall be decided after taking into consideration various factors like building
population, floor area. section of building (compart’mentation), etc.
7. EXIT REQUIREMENTS
7.1.1 An exit may be a doorway; corridor;
passageway(s) to an internal staircase, or external staircase, or to a v e r a n d a h o r terrace(s), which have access to the street, or to the roof of a building or a refuge area. An exit may also include a horizontal exit leading to an adjoining building at the same level.
7.1.2 Lifts and escalators shall not be considered as exits.
7.2 General
7.2.1 Every building meant for human occupancy shall be provided with exits sufficient to permit safe escape of occupants, in case of fire or other emergency.
7.2.2 every building exits shall comply the minimum requirements of this part, except those not accessible for general public use.
7.2.3 All exits shall be free of obstructions.
7.2.4 No building shall be so altered as to reduce the number, width or protection of exits to less than that required.
7.2.5 Exits shall be clearly visible and the routes to reach the exit shall be clearly marked and sign posted to guide the population of the floor concerned. Signs shall be illuminated and wired to an independent electrical circuit on an alternative source of supply.
NOTE-This provision shall not apply to A-2 and A-4 occupancies up to m in height.
7.2.6 Where necessary, adequate and reliable illumination shall be provided for exits.
7.2.7 Fire-resisting doors (see 6.6.1) shall be provided at appropriate places along the escape routes to prevent spread of fire and smoke, and particularly at the entrance to lifts and stairs where a ‘funnel or flue effect’may be created, inducing an upward spread of fire.
7.2.8 All exits shall provide continuous means of egress to the exterior of a building or to an exterior open space leading to a street.
7.2.9 Exits shall be so arranged that they may be reached without passing through another occupied unit.
7.3 Occupant Load-For determining the exits required. the number of persons within
any floor area or the occupant load shall be based on the actual number of occupants, but in no case less than that specified in Table 4.
SL P OF
a) with fixed or loose seats and dance floors without seating facilities
including dining rooms Mercantile:
street floor and sales basement
upper sale floors Business and industrial
load dormitory portions of homes for the aged. orphanages. insane asylums. etc. where sleeping is provided. shall becalculated at not less than gross floor area, person.
gross floor area shall include, addition to the main assembly room or any occupied connecting room or space in storey or in the storeys above or below, where entrance common to such rooms and spaces and they are available for use by the occupants of the assembly place. No deductions shall be made in the gross area for corridors. closets or other subdivisions; the areashall includeall spaceserving the particular assembly occupancy.
7.3.1 ME Z Z A N I N E -The occupant load of a mezzanine floor discharging to a floor below shall be added to that floor occupancy and the capacity of the exits shall be for the total occupancy load thus established.
7.4 of Exits
7.4.1 The unit of exit width, used to measure the capacity of any exit, shall be 50 cm. A clear width of 25 cm shall be counted as an additional half unit. Clear widths less than shall not counted for exit width.
7.4.2 Occupants per unit exit shall be in accordance with Table 5.
7 . 4 . 3 HO R I Z O N T A L EX I T AL L O W A N C E
When horizontal exit is provided in buildings of mercantile, storage, industrial, business and assembly occupancies, the capacity per storey per unit width of exit of stairways in
NATIONAL BUILDING OF INDIA
Table 5 may be increased by 50 per cent; and in buildings of occupancy it may be increased by 100 percent.
TABLE 5 OCCUPANTS PER EXIT WIDTH GROUP OF NU M B E R
No. OCCUPANCY ‘Stairways Ramps Doors‘
ii)
Educational 25 50 75
Institutional 25 50 75
Assembly 40 50 60
Business 50 75
Mercantile 50 60. 75
Industrial 50 60
Storage 50 75
Hazardous 25 30 40
7.5 Arrangement of Exits
7.5.1 Exits shall be so located that the travel distance on the floor shall not exceed the distance given in Table 6.
TABLE 6 TRAVEL DISTANCE FOR OCCUPANCY
GROUP OF
7.5.2 The travel distance to an exit from the dead end of a corridor shall not exceed half the distance specified in Table 6, except in educational, assembly and institutional occupancies in which case it shall not exceed 6 m.
7.5.3 Whenever more than one exit is required for any room space or floor of a building, exits shall be placed as remote from each other as possible and shall be arranged to provide direct access in separate directions from any point in the area served.
7.4 Number of
7.6. I GE N E R A L-The general requirements of number of exits shall supplement the
IV FIRE PROTECTION
requirement of different occupancies in 8 to 16.
7.6.2 All buildings which are more than m i n h e i g h t a n d a l l b u i l d i n g s u s e d a s e d u c a t i o n a l , a s s e m b l y , i n s t i t u t i o n a l , i n d u s t r i a l , s t o r a g e a n d h a z a r d o u s occupancies and mixed occupancies with any of the aforesaid occupancies. having area more than 500 on each floor shall have a minimum of two staircases. They shall be of enclosed type; at least one of them shall be on external walls of buildings and shall open directly to the exterior, interior open space or to an open place of safety. Further. the provision or otherwise of alternative staircase shall be subject to the requirements of travel distance being complied with.
7.7 Doorways
7.7.1 Every exit doorway shall open into an enclosed stairway, or a horizontal exit of a corridor or passageway providing continuous and protected means of egress.
7.7.2 No exit doorway shall be less than in width. Doorways shall be not less than 200 cm in height.
7.7.3 Exit doorways shall open outwards, that is, away from the room, but shall not obstruct the travel along any exit. No door, when opened, shall reduce the required width of stairway landing to less than 90 cm;
overhead or sliding doors shall not be installed.
the case of buildings where there is a central corridor, the doors of roomsshall open inwards to permit smooth flow of traffic in the corridor.
7.7.4 Exit not open immediately upon a flight of stairs; a landing equal to at least the width of the door shall be provided in the stairway at each doorway; the level of landing shall be the same as that of the floor which, it serves.
7.7.5 Exit doorways shall be openable from the side which they serve without the use of key.
7.7.6 REVOLVING DO O R S
7.7.6.1 Revolving doors shall not be used as required exits, except in residential, business and mercantile occupancies, but shall not constitute more than half the total required door width. mercantile buildings where there is a possibility of congregation of a large number of people (more than revolving doors shall not be permitted.
7.7.6.2 Where the revolving doors provided are completely made of glass (plate glass), a
red circle or emblem or logo at 1.5 m level above sill shall be painted on the glass. The thickness of the glass shall be not less than
12 mm.
7.8 Corridors and Passageways
7.8.1 Exit corridors and passageways shall be of width not less than the aggregate required width of exit doorways leading from them in the direction of travel to the exterior.
7.8.2 Where stairways discharge through corridors and passageways, the height of corridors and passageways shall be not less than 2.4 m.
7.9 Internal Staircases
Interior stairs shall be constructed of non-combustible materials throughout.
7.9.2 Interior staircase shall be constructed as a self-contained unit with an external wall constituting at least one of its sides and shall be completely enclosed.
7.9.3 A staircase shall not be arranged round a lift shaft unless the latter is totally enclosed by a material of fire-resistance rating as that for type of construction itself.
7.9.4 Hollow combustible construction shall not be permitted.
No gas piping shall be laid in the stairway.
7.9.6 Notwithstanding the detailed provision for exits in accordance with 7.3, 7.4 and 7.5, the following minimum width shall be provided for staircases:
Residential buildings (dwellings) I.0 m
For row housing 2 storeyes, the width shall be 0.75 tn.
Residential hotel buildings ii) More than 24 m in height institutional like hospitals.
i) Up to beds
ii) More than beds
All
other buildings1.5 m
7.9.7 The minimum width of tread without nosing shall be 25 cm for internal staircase of residential buildings. This shall be 30 cm for assembly, educational, institutional. business and other buildings. The treads shall be constructed and maintained in a manner to prevent slipping.
7.9.8 The maximum height of riser shall be 19 cm for residential buildings and 15 cm for other buildings and the number shall be limited to 15 per flight.
7.9.9 Hand rails shall be provided at a minimum height of 100 cm to be measured from the baseofthemiddleofthetreadstothe top of the hand rails. Further, the gap between the two verticals shall not exceed 30 cm. This gap shall be reduced to 15 cm where children are likely to use the staircase.
The number of people in between floor landings in staircase shall not be less than the population on each floor for the purpose of design of staircase.
7.10 Fire or External Stairs
Fire escapes shall not be taken into account in calculating the evacuation time of a building.
All fire escapes shall be directly connected to the ground.
Entrance to the fire escape shall be separate and remote from the internal staircase.
7.10.4 Care shall be taken to ensure that the wall opening or window opens on to or close to a fire escape.
7.10.5 The route to the fire escape shall be free of obstructions at all times.
7.10.6 The fire escape shall be constructed of materials, and any doorway leading to the fire escape shall have the required fire resistance.
No staircase, used as a fire escape, shall be inclined at an angle greater than 45” from the horizontal.
Fire escape stairs shall have straight than 75 cm wide with 2Ocm treads and risers not more than cm. The number of risers shall be limited to per flight.
Hand rails shall be of a height not less than 100 cm.