Some of the key Passive Fire Protection extract from NBC 2016

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.