Some
of the key Passive Fire Protection extract from NBC 2016
Passive fire protection systems are integrated into the
structure of a building, restricting the spread of smoke and fire to a
compartment that is comprised of fire-rated walls, floors and ceilings. To the
extent possible, all penetrations through these fire-rated walls, floors and
ceilings should be fire stopped in accordance to a tested and approved system.
Additionally, all bottom-of-wall, top-of-wall, and wall-to-wall joints in this
fire-rated compartment should be fire stopped in accordance to a tested and
approved system.
The
use of and need for Passive Fire Protection Products in
buildings/structures are highlighted in the National Building Code of India
(NBC) (2016). It is the job of consultants to design the space, structure of
any type of building whether residential, commercial or industrial. They
design buildings keeping in mind the guidelines outlined in the NBC.
Furthermore, consultants are the ones who determine the types of fire stopping
products to be used in each compartment and their fire rating.
1. Scope:
This Code
(Part 4) specifies occupancy-wise classification, constructional aspects,
egress requirements and protection feature that are necessary to minimize
danger to life and property from fire.
1.2 The
provisions of this part are applicable to,
(a) all
high rise buildings; and
(b)
special buildings, those are,
(1) Hotel,
educational, institutional, business, mercantile, industrial, storage,
hazardous and mixed occupancies, where any of these buildings have floor area
more than 500 m2 on any one or more floors;
(2)
educational buildings having height 9 m and above;
(3)
institutional buildings having height 9m and above;
(4) all
assembly buildings;
(5)
buildings, having area more than 300 m2 of incidental assembly
occupancy on any floor; and
(6)
buildings with two basements or more, or with one basement of area more than
500 m2; unless otherwise mentioned specifically in the provisions.
NOTE - The
owner of the building and parties to agreement, may however decide to apply the
provisions of this part to buildings other than those given above.
2. Fire Resistance
2.28 Fire
Resistance — Fire resistance is a property of an element of building
construction and is the measure of its ability to satisfy for a stated period,
some or all of the following criteria:
a) Load
bearing capacity (Stability) (R) – The ability of a load bearing element to
withstand fire exposure without any loss of structural stability.
b) Integrity
(E) – resistance to penetration of flame and hot gases.
c) Insulation
(I) – resistance to temperature rise on the unexposed face up to a maximum of
180°C and/or average temperature of 140°C.
3. Fire Resistance Rating
Fire Resistance Rating — The time that a material or
construction will withstand the standard fire exposure as determined by fire
test done in accordance with the standard methods of fire tests of
materials/structures as per the accepted standard.
[4(2)] - NOTES - (1.) The requirement of rating of various
building elements as given in this part shall be applicable in accordance with
the provisions given in the accepted standard [4(2)].
(2.) The fire
resistance rating shall be specified in minutes. (3.) Fire resistance rating
for non-structural material / assembly shall bear a label of compliance to such
ratings as per the approval of competent authority based on testing and
evaluation. The label shall be permanently affixed to the material / assembly
and may carry other relevant details such as name and type of the product, and
manufacturer's details.
4. Fire Resistance Wall
Fire Resistant Wall (2.30) — Fire resistant rated wall,
having opening(s) with specified fire resistant rating, which restricts the
spread of fire from one part of a building to another part of the same
building.
5. Fire Stop
Fire Stop
(2.32 ) — A fire resistant material, or construction, having a fire resistance
rating of not less than the fire separating elements, installed in concealed
spaces or between structural elements of a building to prevent the spread/
propagation of fire and smoke through walls, ceilings and like as per the laid
down criteria.
NOTES -
(1) Fire stop assembly for through penetrations is a combination of firestop
compatible for use with the penetrant, penetration items such as cables, cable
trays, conduits, ducts, pipes etc., and their means of support through the wall
or opening that together restores the fire resistance rating of the fire
separating elements in terms of its integrity and/or insulation properties.
(2) Fire
stop assembly for joints is the one where fire stop with movement capability is
used to seal the linear joints between adjacent fire separating elements, which
should be installed within its tested design limits with regard to size of
joint, type of assembly, and anticipated compression and extension of the
joint.
6. Fire Wall or Fire
Separating Wall
Fire Wall
or Fire Separating Wall (2.34) — A fire resistance rated wall having fire
protected openings, which restricts the spread of fire and extends continuously
from the foundation to the roof (and through the roof at least 1m above the
roof in case of combustible roof), with sufficient structural stability under
fire conditions to allow collapse of construction on one side or either side
without collapse of the wall.
7. High Rise Building
High Rise
Building (2.38) — A buildings 15 m or above in height (irrespective of its
occupancy).
8. Smoke Barrier
Smoke
Barrier (2.56) — A continuous membrane, or a membrane with discontinuities
created by protected openings, where such membrane is designed and constructed
to restrict the movement of smoke.
9. Smoke Compartment
Smoke
Compartment (2.57) — A space within a building enclosed by smoke barriers on
all sides.
10.Restriction on Existing
Building
Restrictions
on Existing Buildings (3.2.7) – The existing buildings in any fire zone shall
not be required to comply with the requirement of the Code unless these are
altered, or in the opinion of the Authority, such building constitutes a hazard
to the safety of the adjacent property or the occupants of the building itself
or is an unsafe building. In the event of alteration, it shall be necessary to
obtain permission of the Authority for such alteration consistent with fire
hazard (see Part 2 ‘Administration’ of the code). Alterations/modifications/renovations
shall be accomplished so as to ensure conformity with all the safety
requirements of the new buildings. Such alterations shall not in any way bring
down level of fire and life safety below that which existed earlier. Any
addition or alterations or construction of cubicles or partitioning, for floor area
exceeding 500 m2 for all high rise buildings shall be with approval
of local fire authority.
11. Str. & Non Stru
Fire Resistance Rating (3.3.2)
It is
required that a structural and/or non-structural element/component shall have
the requisite fire resistance rating as per Table 1. The fire resistance rating
for the structural and non-structural elements shall be based on guidelines as
per approved and acceptable standards. The fire rating shall be validated and
certified with a view to meeting the requirements of Table 1. In the absence of
any validated/certified rating, guidance may be obtained from the information
available in Annex C.
12. False Ceiling (3.3.4)
The false
ceiling, including all fixtures used for its suspension, shall be of
non-combustible material and shall provide adequate fire resistance to the
ceiling in order to prevent spread of fire across ceiling.
13. Wording Change
(3.4.5.2)
For Types 1 to 3 constructions, a doorway or opening in a fire resistant wall
on any floor shall be limited to 5.6 m2 in area with a maximum
height/width of 2.75 m. Every wall opening shall be protected with
fire-resisting doors, having the fire rating of not less than 120 min. The
openings in the floors shall be protected by vertical enclosures extending
above and below such openings, having a fire resistance of not less than 120
min and all openings therein being protected with a fire-resisting assembly as
specified in 3.4.5.6.
(3.4.5.3) For Type 4 Construction, openings in the fire
separating walls or floors shall be fitted with 120 min fire-resistance rated
assemblies.
14. Service Ducts &
Shafts
Service
ducts and shafts (3.4.5.4): Openings in walls or floors which are necessary to
be provided to allow passages of all building services like cables, electrical
wirings, telephone cables, plumbing pipes, etc., shall be protected by
enclosure in the form of ducts/shafts having a fire resistance not less than
120 min. The inspection door for electrical shafts/ducts shall be not less than
120 min. Further, medium and low voltage wiring running in shafts, shall either
be armored type or run through metal conduits. Further, the space between the
cables/conduits and the walls/slabs shall be filled in by a fire stop material
having fire resistance rating of not less than 120 min. This shall exclude
requirement of fire stop sealing for low voltage services shafts. For plumbing
shafts in the core of the building, with shaft door opening inside the
building, the shafts shall have inspection doors having fire resistance rating
not less than 30 min. For plumbing shafts doors which open in wet areas or in
naturally ventilated areas or on external wall of the building, the shafts may
not require doors having any specified fire rating.
15. Electrical
Installations
Electrical
Installation (3.4.7) For requirements regarding electrical installations from
the point of view of fire safety, reference may be made to good practice
[4(8)]. (see also Part 8 ‘Building Services, Section 2 Electrical and Allied
Installations’ of the Code).
The
electric distribution cables/wiring shall be laid in a separate shaft. The
shaft shall be sealed at every floor with fire stop materials having the same
fire resistance as that of the floor. High, medium and low voltage wiring
running in shaft and in false ceiling shall run in separate shafts/conduits.
16.Air Handling Unit
(3.4.8.2.2)
Shafts or ducts, if penetrating multiple floors, shall be of masonry
construction with fire damper in connecting duct work or shall have fire rated
ductwork with fire dampers at floor crossing. Alternatively, the duct and
equipment may be installed in room having walls, doors and fire damper in duct
exiting/entering the room of 120 min fire resistance rating. Such shafts and
ducts shall have all passive control meeting 120 min fire resistance rating
requirement to meet the objective of isolation of the floor from spread of fire
to upper and lower floors through shaft / duct work.
17.Duct Work
(3.4.8.3.3)
Wherever the ducts pass through fire walls or floors, the opening around the
ducts shall be sealed with materials having fire resistance rating of the
compartment. …….
3.4.8.3.5
The material used for insulating the duct system (inside or outside) shall be
of non-combustible type. Any such insulating material shall not be wrapped or
secured by any material of combustible nature.
18. Glazing
(3.4.10.1)
The glazing shall be in accordance with Part 6 'Structural Design, Section 8
Glass and Glazing' of the Code. The entire glazing assembly shall be rated to
that type of construction as given in Table 1. This shall be applicable along
with other provisions of this part related to respective users as specified
therein. The use of glass shall not be permitted for enclosures of exits and
exit passageway.
19. Glass Façade
Requirements
(3.4.10.2)
Glass facade shall be in accordance with the following: -
a) For
fully sprinklered buildings having fire separation of 9 m or more, tempered
glass in a non-combustible assembly, with ability to hold the glass in place,
shall be provided. It shall be ensured that sprinklers are located within 600
mm of the facade glass providing full coverage to the glass. NOTE – In case of
all other buildings, fire resistance rating of glass facade shall be in
accordance with Table 1. b) All gaps between floor-slabs and facade assembly
shall be sealed at all levels by approved fire resistant sealant material of
equal fire rating as that of floor slab to prevent fire and smoke propagation
from one floor to another. c) Openable panels.....,
20.Fire Command Center
(3.4.12)
Fire Command Center (FCC) (d) The fire staff in charge of fire command center
shall be responsible for the maintenance of the various services and
firefighting installations in coordination with security, electrical and civil
staff of the building.
21. Exit Requirements
(4.2)
General Exit Requirements
(4.2.17)
Penetrations into and openings through an exit are prohibited except those
necessary like for the fire protection piping, ducts for pressurization and
similar life safety services. Such openings as well as vertical passage of
shaft through floors shall be protected by passive systems.
22. Protected Escape Routes
(4.4.2.5) Smoke
control of exits
(a) In
building design, compartmentation plays a vital part in limiting the spread of
fire and smoke. The design should ensure avoidance of spread of smoke to
adjacent spaces through the various leakage openings in the compartment
enclosure, such as cracks, openings around pipes ducts, airflow grills and
doors. In absence of proper sealing, smoke and toxic gases will obstruct the
free movement of occupants of the building through theexits. Pressurization of
staircases is of great importance for the excusion of smoke and toxic gases
from the protected exit.
23. Compartmentation Area
(4.5.2)
All floors shall be compartmented/zoned with area of each compartment being not
more than 750 m2. The maximum size of the compartment shall be as
follows, in case of sprinklered basement/ building:
In
addition, there shall be requirement of a minimum of two compartments if the
floor plate size is equal or less than the areas mentioned above. However, such
requirement of minimum two compartments shall not be required, if the floor
plate is less than 750 m2.
Compartmentation
shall be achieved by means of fire barrier having fire resistance rating of 120
min.
1. Additional requirements for high rise
buildings
Annex E -
Additional requirements for high rise buildings
For high
rise buildings, seismic bracings shall be considered for fire-fighting
installations depending on seismic vulnerability of the region and type of
occupancy.
2. E-7 Fire and Life Safety Audit
Annexure
E: Clause E-7
a) Fire
and life safety audit shall be carried out for all buildings having a height of
more than 15 m.
b) Such
audits shall preferably be conducted by a third-party auditor having requisite
experience in life safety inspections.
c)
Frequency of such audits shall be once in two years.
3. Annex J - Fire and life safety requirements
for metro stations.
J-6 Fire
separation and compartmentation -
J-6.1 Fire
compartments shall be provided in transit stations in accordance with the
provisions of this section. Fire ratings of various occupancies within open
stations and enclosed stations shall be as indicated in Table 27.
J-6.2
Further transit station shall be divided into fire compartments by means of
compartment walls and compartment floors by a fire separation of at least 120
min between following occupancies:
a) Public
area and non-public area,
(b)
transit and non-transit area, and
(C)
Ancillary areas located beneath and within 3m of the train way in open
stations.
J-6.3 No
fire separation shall be required for occupancies like ticketing offices,
toilets, other offices and the like.
J-6.4
Incidental kiosks inside stations for other purposes like commercial use, etc.
shall be fire separated (120 min rating) from the station building, if areas
occupied by such occupancies exceed 6 m2.