APPENDIX A: Guidelines for Fire Drill and Evacuation Procedure for High Rise Buildings
APPENDIX B: Fire Protection Considerations for Venting in Industrial and Storage Buildings
APPENDIX C: Detailed Guidelines for Selection and Siting of Fire Detection System
APPENDIX D: Special Requirements of Buildings more than 20 Metre High
APPENDIX A Guidelines for Fire Drill and Evacuation Procedure for High Rise Buildings
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A2
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Appendix A Guidelines for Fire Drill and Evacuation Procedure for High Rise Buildings INTRODUCTION The following guidelines are provided to enable safe evacuation of the occupants of a high rise building in case of fire or any other emergency. FIRE REPORTING Any occupant within the occupancy discovering a fire, heat or smoke, shall forthwith report the incident to the fire brigade directly or through the ground command station, if there be any. Reporting of emergency situation to fire brigade should not be unnecessarily delayed by any person by way of making, issuing, posting or maintaining any regulation or order, written or verbal, to that effect. FIRE DRILLS Fire drill shall be conducted quarterly (4 times a year) in existing buildings as detailed under the Fire Safety Plan (Sec A 4.7 and A 4.8 below) for the first two years from the data of enforcement of this Code. For new buildings, the period of 2 years shall be counted from the beginning of occupancy of the building. After this initial period of 2 years, fire drill shall be conducted twice a year in all buildings. All occupants of the Paling. shall participate in the fire drill and the building service employees includin| fire warden and his/her staff shall actively help the inmates in the process ae drill. However, the very old, convalescent patients or otherwise incapacitated inmates are not obliged to actively take part in the exercise, except the fire warden and his staff and family members of such penn shall chalk out a clear plan as to how to evacuate in a real emergent situation with such incapacitated persons. A may of such drills shall be kept in writing for at least 3 years for the inspection of fire brigade whenever ca or. SIGNS AND FLOOR PLANS A sign shall be cs and maintained in front of the landing area of lifts on all floors so conspicuously and in such size and colour (sign reference may be given) that occupants may not miss the same, which shall direct the occupants to use stairs and not Tits during emergencies /fires, if not directed otherwise and shall also contain a floor plan with exact location of the stair and the relative position between the sign and the stair. Such posting in front of the landing area of lifts shall be omitted only if such signs are posted on all floors and some other area conspicuously located with the same message inscribed on it. The sign shall be written in Bangla, English translation of which reads “USE STAIRS IN CASE OF FIRE UNLESS OTHERWISE INSTRUCTED”. The lettering shall be at least 25 mm in red on white background. the sign should be so written as to Laisa good legibility. When floor plan with stair location is shown, the si; shall be at least 250x300 mm. en two signs are used, one for the notice and the other for floor plan, the sizes shall at least be 60 x 300 mm and 200 x 300 mm respectively. The sign/signs may be posted directl above the call button of the lift or any other conspicuous location securely attached to the surface of the wall. The top of the sign shall not be more than 2 metres above floor level. Signs Depicting Floor Number ; A sign shall be posted and maintained on each stair enclosure preferably on the wall of the intermediate landing which in actual fact shall be half storey more or less than the actual indicating the floor number. The number shall be at least 75 mm square and in Bangla. The number and background shall be in contrasting colours, e.g. black on a white background. Stair and Elevator Identification Each stair and Elevator shall be identified by an alphabet in Bangla and posted with a sign and securely placed preferably on the wall of the stair side of the lift door from which a is to be made. The letters shall be 75 mm square and shall be painted on a contrasting background e.g. black on a white background. Stair re-entry Provision A sign shall be posted and maintained on each floor within stairway and on the occupancy side of the stairway where required, indicating whether re-entry is provided into the building and the floor where such re-entry is provided. The lettering and numbers of the signs shall be at least 25 mm high on a contrasting beckgeound: and shall be posted securely at least 1.5 m above the floor. Command Station Command station on the ground floor shall be provided with a detailed floor plan of the entire building including detailed locations of all first aid fire fighting equipment and other pertinent information. Command stations shall be adequately illuminated.A46 Two way Communications and Fire Alarm
A two way communication system between each floor and the command station on the lobby of the entrance floor shall be provided and maintained by the owner of the building. Similarly fire alarm on each floor and the command station shall be fitted and maintained. A47 Fire Safety Plan . A fire safety plan shall be developed in line with the details elaborated under A 4.8 and must have the approval of the local Fire Department regarding its adequacy. A 4.7.1 Once the bia is accorded after ele by the Fire Department, the plan shall be distributed to all the tenants of the building by the building management, (be it a committee or a cooperative) including the employees of the tenants and employees of the management. A 4.7.2 If the building is owned by an individual or a single corporate body and the owner or right holding member/members of the corporate body are residing in the building, shall be equally subject to fire safety plan applicable to other tenants. A4.7.3 All major changes in the safety plan shall be promptly reported to Fire Department for their approval.A48 Fire Safety Plan
Fire Safety Plan elaborates the purpose and objective of the plan with details of personnel and their duties and fire drilling and evacuation plan. A 48.1 Fire Safety Plan starts with the location, address of the building with telephone number and details of any other communication facilities available within the building. A48.2 Purpose of the plan is to delineate details of systematic safe and orderly evacuation of a part or whole of the building by its occupants in case of fire/emergency in the shortest possible time to a safe area through the safe means of egress. It also details out the use of in-built facilities of fire warning and fire fighting like fire alarm, first aid an etc. to safeguard the lives of the inmates of the building. A4.8.3 Objective of the plan is to provide continued education to the inmates and the fire command personnel and keep the people oriented to the in-built equipment in readiness to act in the event of fire. The plan shall be rehearsed through fire drill and the written plans containing instruction shall be updated if needed and use of the in-built equipment along with initiating fire safety procedure to safeguard life in case of fire until the fire brigade arrives. ; A484 Fire command crew may be cris Pe of personnel like Fire ia Director, Deputy Fire Safety Director, Fire Wardens and Deputy Fire Wardens. Number of these people shall be dependent on the size and number of inmates living within the building. A 4.8.4.1 a) Fire Safety Director: The plan shall contain the name, whether employed by a fire security firm or directly employed by the management, assigned regular location, how to contact him at his/her regular location, how to contact him/her if not at regular location during normal working hours. b) Qualifications and experience: Depending on the size and complexity of the building, the Director shall be a person of proven capability, having good ra bay Soe schooling with adequate experience in dealing with fire. Preference may be given to retired Fire Department personnel. c) Duties of Fire Safety Director shall primarily include but not be limited to the following. i) Shall be well conversant with the written fire safety plan for the fire drill and evacuation procedures. ; ii) Shall be in charge of selecting qualified building service employees for the fire command and . engage in organizing, training and supervising the works of command crew. iii) Shall be responsible to conduct fire and evacuation drill. iv) Shall be responsible for the availability and state of preparedness of fire command crew during emergencies. v) Shall be responsible for the assignment and training of Fire Warden on floor supported by adequate number of Deputy Fire Wardens as detailed out in the fire safety plan. vi) Shall be responsible for the day to day supervision of the warden and his deputies and the state of alertness of the crew. When the number of crew of Warden and Deputy Wardens become such that it becomes impractical for the Director to check them directly during the working hours, the Warden or Deputy Warden shall intimate the Director for the persons not available for some length of time, so that he may provide substitute during such period of absence. Nonetheless the Director shall spot check any number of floors as he wishes or time permits. An up to date organization chart shall be displayed at appropriate locations. vii) Cases of negligence to duties on the part of members of his crew shall be taken up by him and he shall rectify the situation by appropriate measures as far as he has been empowered under the fire safety plan failing which he shall notify the matter to the owner or the management of the building. The owner or the management on their part shall take up the matter with the fire security firm or if employed directly shall deal with the matter directly. If the person/persons is/are employed by a firm, and the firm fails to correct the situation, the owner /management shall notify the matter to the Fire Department to take disciplinary action against the firm. viii) In the event of fire/emergency he/she shall be in charge of fire command station and shall supervise, guide and coordinate activities such as ensuring that the Fire Department has been notified of fire or fire alarm, direct the evacuation procedure as detailed in the fire safety plan, manning the fire command station, appraise the Fire Department about the spot of fire on their arrival, advise the Fire Department officer in charge of the operation. A 4.8.4.2 a) Deputy Fire Safety Director: The fire safety plan shall contain the details of Deputy Fire Safety Director similar to the details mentioned under the Director A 4.8.4.1(a). b) Qualification and experience shall also be similar to those of the Director excepting that he may be less experience than the Director and covered under A 4.8.4.1 (b). c) Duties of the Deputy Fire safety Director shall be similar to those mentioned under A 4.8.4.1(c) except that he shall receive command from the Director for execution and shall assume the role of Director in his absence. A 4.8.4.3 a) Fire Warden and Deputy Fire Wardens: The fire safety plan shall contain their names on the organization chart for the floors they have been assigned against. The entire organization chart shall be kept updated in the command station for fire drill and evacuation assignment. b) Tenant or tenants of each floor upon request by the owner or in-charge of the building shall assign and make available dependable and trustworthy person/persons under their employee at the disposal of the Director to act as Wardens, Deputy Wardens. They shall undergo basic fire fighting and evacuation training by the Director or his deputy. c) Each floor of a building shall be under the command of a Fire Warden and each tenant under a Deputy Fire Warden for the safe evacuation of inmates in the case of fire. When the floor area of a tenant exceeds 700 m? a Deputy Fire Warden shall be assigned for each 700 m? or part thereof. i) Each Fire Warden and Deputy Fire Warden shall be conversant with the fire safety plan. They must be well acquainted with fire exits and location and operation of fire alarms. ii) In case of fire or fire alarm, the Fire Warden and Deputies shall ascertain location of fire and unfold evacuation procedure as directed from the command station and to the following general guides.- The most critical area for immediate evacuation would be the fire floor and the floors above. Evacuation from other floors shall be initiated if so commanded by the ground command station or the situation indicates to be so. Evacuation should be carried out via stairs not influenced by fire and fire warden shall try to carry out the operation using stair other then the ones used by the Fire Department personnel. If this become impossible, the wardens before fame door to the fire floor shall sought advice from the Fire Department personnel.
- Evacuation to two or more floors below the fire floor should be adequate. He/She shall continuously keep the ground command station informed of his/her location.
- Ensure that fire alarm has been transmitted.
- Fire Wardens and their deputies shall ensure that all the inmates are intimated of the excegency and shall immediately proceed with the evacuation exercise detailed under Fire Safety Plan.
- Fire Warden shall keep the ground station informed of the step being taken by him/her.
- Similarly Fire Warden above fire floor shall notify the command station of the means being taken by him/her or any other special feature after unfolding Fire Safety Plan.
- If and when stairways serving fire floor/floors above become useless by the presence of fire, smoke, fumes, in several floors above and when fire engulfs a considerable number of inmates then use of elevators shall be considered in accordance with the followings:
- If the elevator serving the floor to be evacuated also serves the fire floor, the lifts shall not be used. If there are more than one lift bank, however, the lift/lifts in the other bank may be used if notified by the ground command station that one may use such lift/lifts.
- If the lifts do not serve the fire floor or lift shaft has no opening on the fire floor, they may be used if not otherwise instructed by the command station.
- Elevators taken over by trained in-house person or Fire Department personnel may be used.
- In absence of unaffected available lift/lifts, Fire Warden shall decide to use the safest stairway for evacuation based on considerations /information available on the floor and any other instruction received from ground command. Before entering the stairway with the evacuees, the Fire Warden shall be sure about the environment within the stairway by personal inspection and in case of adverse environment‘consider using an alternate stairway and shall notify the ground command accordingly.
- The Fire Warden shall keep the ground command informed of the means adopted by him during the evacuation process. A 4.8.4.4 a) Building Evacuation Supervisors: A Building Evacuation Supervisor shall be available at all times other than normal working hours when the Fire Safety Director or his Deputy are not available within the building. b) Building Evacuation Supervisor shall be a person capable of directing the evacuation procedure of occupants within the buildings as detailed in the Fire Safety Plan. c) During fire/emergencies, his primary function shall be to take over command of the ground station and to direct and execute the evacuation process as laid down in the plan.
A485
A48.6
number of Wardens and Deputy Wardens are inadequate, a Fire Party shall be raised from among the employees of the tenants and the management who shall be acting as help to regular in-house fire fighting force in the event of fire and follow the same work schedule and fancbda in the same manner as Wardens/Deputy Warden. Organization Chart for Fire Drill and Evacuation Assignment a) An organization chart clearly yay tase et attributed to designated employees shall be prepared as per Fire Safety Plan and posted to all tenants and in very conspicuous location/locations on each floor. A copy of the chart shall be in possession of the Fire Safety Director. b) An updated list shall be continuously made available withthe Director, his Deputy and Fire Wardens and their deputies for all the disabled occupants unable to move without aid in the stairs. Arrangement shall be made in detail in the Fire Safety Plan to have these inmates assigned in moving down the stairs two or more floors below fire floor. If it becomes ReCeerY to move them still further down the stair, help may be sought of the elevator bank unaffected by fire and evacuated safely to ground floor. In case any extra assistance is needed, the Director shall be notified. c) During fire or fire drill exercise, Fire Wardens shall be using arm band or such other identification. d) During fire on the fire floor it is to be ensured that all inmates are notified and are evacuated to safe area. A rush search shall be carried out including lavatories that all the inmates have been covered arid the person in charge of this operation shall be trained in accomplishing this task fast and flawless. e) Persons not available on duty as per organization chart shall be promptly replaced as per contingency plan detailed in the Fire Safety Plan. f) On completion of evacuation operation, a head count shall be carried out of all the regular occupants known to have occupied the floor evacuated. g) Immediately on receipt of the alarm, the Fire Wardens shall take position near the two way communication station on the floor, so that he/she can maintain continuous contact with the ground command and receive instructions. Instruction to Inmates of the Building: Once the Fire Safety Plan has been approved by the Fire Department, the applicable portion of the plan shall be distributed to all the tenants and the management of the buildin; who in turn shall pass it on the their respective employees. All the occupants shall actively participate an: cooperate in carrying out the provisions of Fire Safety Plan. A 4.8.7 Fire Prevention and Protection Program: A Plan for periodic formal inspection of each floor shall beA48.8
A48.9
developed in respect of exit facilities, fire pied nin and good house keeping. Reports of such inspection shall be carefully maintained for inspection of Fire Department. The Plan shalttiave provision for monthly testing of two way communication and fire alarm system. Detailed Building Information: A form shall be maintained for the benefit of all concerned with fire hazard of the building and shall contain the following basic information. a) Building address in adequate details about its location. b) Name, Address and telephone number of the owner (corporate body or individual) and the person in charge of the building. c) Name address and telephone number if any, of the Fire Safety Director and his Deputy. d) Certificate of occupancy. e) Height, area, construction class (details of various load and non-load bearing elements). f) Number, type and location of fire stairs and/or fire towers. g) Number, type and location of horizontal exits or other refuge areas. h) Number, type location and operation of elevators and escalators (if any). i) Locations of fire alarm — floorwise and central. j) Communication System (telephone, walkie talkie). k) Size and location of stand pipe system, gravity or pressure tank, fire pump and the name and qualifications of the person or persons in charge of the facilities.- Automatic fire sprinkler system, primary and secondary water supply system and the area or areas being protected along with the name and qualification of the person or persons in charge. m) Any other fire extinguishing systera, their location, efficacy and other pertinent details.
- Average number of disabled persons visiting the building by day and night. p) Average number of outsiders visiting the building by day and night.
A4.8.11.1 English Text of Instruction
a) Safety First b) d)- Push button fire alarm boxes (number is mentioned here) are provided on your floor. Please read the operating instruction posted on them. - Please read the oes instructions on the body of the fire cal rovided in your floor.
- Nearest exit from your flat is shown in this plan (plan to be provided chy
- Assemble on the ground floor at the location indicated on the following plan. For clarification, Sa the Warden or Deputy Warden. (plan of assembly point in poles floor to be provided ere) For personal and collective safety, notify the Warden/Deputy Warden in case.
- Exit route and/or door are‘obstructed by dumping of boxes or such other loose materials.
- Staircase door, lift lobby doors do not close mgt ion or completely. ‘
- Push button fire alarm or fire extinguisher are obstructed or damaged or seem to be out of order.
- Break the glass and push the button of the nearest fire alarm and call the fire service.
- With assistance from the floor Warden if needed, fight fire with the in-built facilities on your floor.
- Evacuate, if so instructed by the Warden
A4.8.11.2 Bangla Text of Instruction
ক) সতর্কতাই সর্বোৎকৃষ্ট রক্ষা ব্যবস্থা খ) নিজের এবং সামগ্রিক নিরাপত্তার স্বার্থে… গ) আপনি যদি কোথাও আগুন দেখতে পান ঘ) স্থান ত্যাগের নির্দেশ পাওয়ার সাথে সাথে নিম্নলিখিত ব্যবস্থা গ্রহণ করবেনAPPENDIX B Fire Protection Considerations for Venting in Industrial and Storage Buildings
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B11
B12
B2
B21
B2.1.1
B2.1.2
B2.1.3
B2.1.4
B2.1.5
B2.1.6
B2.1.7
B2.1.8
B2.1.9
B2.1.10
B2.1.11
Appendix B Fire Protection Considerations for Venting in Industrial and Storage Buildings SCOPE This appendix covers venting requirements in industrial buildings. Provisions contained herein shall be applicable to single storey factory and storage facilities requiring large floor areas without dividing walls and enclosures. This annex does not cover fire and smoke venting requirements for tall buildings. Venting requirements in industrial buildings are specified in this appendix under two heads as follows : a) Smoke and fire venting b) Explosion venting SMOKE AND FIRE VENTING The following provisions shall be complied with for fire and smoke venting. The combustion product of fire including smoke, being lighter than surrounding air tend to accumulate near the high point of a structure and tend to spread out in all directions to form a floating layer on top of a relatively cool air below. In absence of vent, the hot floating layer progressively become pales and the whole occupancy is engulfed with smoking hot gases. Time needed to reach this stage may be only a few minutes depending on the type of materials on fire, storage conditions of the materials involved etc. Convection current of air always help lateral spread of fire once the hot gases reach the roof. Adequate number of vents, properly fre ee and judiciously placed, can disperse the smoke and hot gases to atmosphere, thereby prevents spread of fire, as well as reduces risk of explosion from unburnt gases. Time needed for accumulation of hot gases and smoke within the structure being very short, it is imperative that the venting devices are to be so designed and installed that they operate automatically at the earliest sign of fire, sensed through smoke and heat detectors. The smoke and fire venting system shall be so designed and installed as to keep the temperature of the combustion product as low as possible, preferably below 150°C. Venting systems are complement any of the to fire extinguishing system. Where automatic sprinklers are installed as fire extinguishing system, the sprinklers shall operate before the vent system comes into operation. It is obvious that the smoke venting is easier than cleaning smoke once the structure has been filled with it. Apart from large area factory and storage, venting may be considered essential for windowless buildings, underground structures and hazardous occupancies. Automatic fire vents shall be provided in all industrial and storage buildings classified as medium hazard or above, with floor areas in excess of 750 m2, This provision is mandatory irrespective of whether a large area is compartmentalized or not. Determination of precise venting requirements is difficult, as variables like rate of combustion vis-a-vis nature, shape, size and packaging of the combustible materials as well the size, height and disposition of the stacks of materials are involved with it. Industrial buildings having floor area less than 750 m? and which is rated as low hazard industry, may use conventional ventilators fitted high above near the eaves of the external walls as vents for smoke and hot ases, provided opening of the ventilators can be ensured at all times or are designed to open automatically in case of fire. Because of the large volume of air present in the large industrial buildings, it is most unlikely that the closure of doors and windows shall eventually extinct the fire. B 2.1.12 It is usually the vertical and not horizontal ventilation that is adopted in the single storey industrial buildings. B 2.1.13 Heat produced in fire being 70 to 80 per cent connective in nature, suitable arrangements shall beB2.1.14
incorporated in the vent system for early outflow of heat to atmosphere to contain fire spread. To minimize venting problems use of combustible roof linings shall be avoided. B 2.1.15 Wind produces a negative pressure when blowing across a flat roof or a roof with a pitch under 40°. Negative pressure tend to draw gases out of the structure, thereby aids venting of hot gases and smoke.B2.1.16
To achieve full efficien Conversely when the pitch is more than 40°, gases will be drawn inside and will oppose outward flow on the windward side of the roof. cy in vents total area of cold air inlets into the buildings should be at least equal to total areas of all vents. Ideally the inlets should be as close to the ground as possible. B 2.1.17 When vents are installed, the size, design, number and disposition and associated roof screen or curtain boards shall be carefully assessed. B2.2 Venting area i, oar ong for ventilation are estimated largely on the basis of assumed time needed between the build up of fire from the initial outbreak to the time of effective taking over by the fire brigade. B 2.2.1 Because the entrained air forms the bulk of the vent gases, it is natural that the vent area required to be provided shall be proportional to the perimeter of the fire area. F B 2.2.2 The effective area shall be the minimum cross-sectional area through which the hot gases must flow out to atmosphere. B 2.2.3 Increased air movement generated by power operated fans shall be disregarded in deciding venting area because it is assumed that in the event of fire power will be disrupted and/or fan damaged. B2.2.4 Effective vent opening shall be different for different occupancies but shall be proportional to the floor area. The ratios of total vent areas to be provided to the floor area are as shown below: a) Low hazard industry 1:150 b) Moderate hazard industry 1:100 c) Hazardous occupancy 1:30 to 1:50 B2.3 Venting shall be accomplished by any of the types, such as monitors, continuous gravity type, unit type or sawtooth roof skylights. B 2.3.1 Wire glass or metal panels shall be used in monitor type vents only if arrangements can be made for its automatic opening. B 2.3.2 Use of plain thin glass shall be avoided because of its doubtful behaviour during fire. However, if glass or other early disintegrating suitable plastic materials are used, they should be designed for automatic operation. B 2.3.3 In monitor or unit type vents, the panels shall be hinged at the bottom and bm era to open automatically. Both leaf of the vent shall be designed to vent simultaneously disregarding wind direction and ensure their effectiveness during fire. B2.3.4 Moveable shutters in continuous gravity vents shall be designed to open automatically in case of fire. B2.3.5 Unit type vents shall be relatively small ranging between 1 and 9 m?in area, have light weight metal frames and housed with hinged dampers. They shall be designed for both automatic and manual operation. B2.3.6 Roof skylight shall be satisfactory for venting only if designed for automatic operation. B 2.3.7. Exterior wall windows alone in industrial buildings shall not be accepted as satisfactory means of ventin; but may be reckoned as additional means of venting when located close to the eaves and are provided wit ordinary glass or movable section arranged for both manual and automatic operation. B2.3.8 Because of substantial reduction in the effective venting area, baffles shall not be installed inside vents. B2.4 Vents shall be automatic in operation unless where designed specifically for both manual and automatic operation. B 2.4.1 The release mechanism shall be simple in operation and shall not be dependent on electric power for operation, as power operation may be disrupted during fire. B 2.4.2 The automatic operation of vents can be achieved by actuation of fusible links or other heat or smoke detectors or by interlacing with the operation of sprinkler system or any other automatic fire eee system covering the area. The vents can be so designed as to open by counterweights utilizing the force o} gravity or spring loaded level following its release. B2.4.3_ For simultaneous operation automatic fire alarm and automatic vent system shall be coupled. B2.4.4 Vents and automatic sprinklers where installed together, sprinkler shall go into operation first before vents open, in order to avoid delay in sprinkler irae Heat actuated devices, if used for vent release, shall be properly covered from water spray or sprinkler which might delay their action.B2.4.5
B2.4.6
B25
B2.5.1
B25.2
B2.5.3
B2.5.4
B2.5.5
B2.6
B2.6.1
B2.6.2
B2.6.3
B2.6.4
B26.5
B2.6.6
B2.6.7
B3
B3.1
B3.1.1
B3.1.2
B3.1.3
To ensure vent opening, release mechanism shall not only be joined to fusible links but also with smoke actuated automatic fire detectors, where the height of roof apex of the occupancy is 10 m or more or the materials handled or stored have high smoke producing characteristics. Materials used in hinges, hatches and other related parts in vents shall be noncorrosive in nature for long trouble free operation. Vents shall be properly sited, always as far as possible at the highest point in each area to be covered. As far possible vents shall be sited right on top of the probable risk area to be protected to ensure free and speedy removal of smoke and other combustion product. Minimum vent opening shall not be less than 1250 mm in any direction. Vent spacing shall be designed considering the fact that higher number of smaller vents are better than smaller number of large vents. Maximum spacing of vents shall be as follows: a) Low hazard occupancy 45 m between centres b) Moderate hazard occupancy 36 m between centres c) Hazardous occupancy 22.5 to 30 m between centres In deciding location of the vents on roof Sec B 2.1.15 shall be adhered to as far as possible. Industrial buildings having large floor area without separating or subdivision walls shall be compartmentalized with the aid of roof screen or curtain boards. The curtains are extended from the roof downward at specific intervals preventing lateral spread of heat and smoke in the event of fire. Curtain board materials shall be heavy sheet metal or any other noncombustible material capable of withstanding damage by heat or impact. The curtain boards shall be reasonably gas-tight, although small openings for passage of pipes conduits etc. may be permitted. They shall extend at least up to 2200 mm from the downside of roof. Sites of special hazard shall be enclosed by roof curtains extending down to 400 mm. They shall extend down to a height of 300 mm from the floor where the roof/ceiling exceeds 15m or more. In moderate hazard occupancies the distance between the screens shall not exceed 75m and enclosed areas (compartmentalized) shall not exceed 4500 m?. In high hazard occupancies the distance between the screen shall not exceed 30m and enclosed area shall be limited to 750 m?, The enclosed roof area shall be so spaced and disposed as to create an effective area for disposing off smoke and hot gases of combustion. In buildings provided with sprinklers, the screens shall preferably be so located as to coincide with unit areas of sprinkler system. EXPLOSION RELIEF VENTS Explosior. relief vents shall be provided in industrial premises where combustible dusts, flammable gases, vapours or mists in concentrations capable of initiating an explosion are present and constantly keep the premises under the threat of explosion hazards. Magnitude of pressure developed may range around 7x10° N/m? and ordinar ee will not be able to withstand shock that will be produced from such explosion. Such buildings shall be fitted with explosion relief vents to prevent structural damage. Most ordinary buildings will not be able to stand under a sustained internal pressure of 7x10° N/m?. Consequently the vents shall be so designed as to operate at a pressure much below the pressure at which the walls shall crumble down. Pressures rises with an explosion within an enclosure, even when vents are open and unobstructed. As a result any delay in opening venting devices further increase the pressure. It is possible to isolate hazardous operations and equipment outside of buildings with a pressure resisting wall which will reduce risk of structural damage. Such operations and equipment may be housed in a single storey building having appropriate venting facilities and a device to absorb explosion shock from blowing through the duct back to the building. B 3.1.4 Sometimes it may not be possible to house hazardous operations and equipment outside of the building, in which case the separation from other parts and equipment shall be achieved by pressure resisting walls and such units shall be ventilated outdoors. If suitable vents are integrated, external walls may be of heavy construction or of heavy panel which may be blown off easily. B 3.1.5 No hazardous equipment or operations shall be permitted to be located in the basement or partially underground structure. B3.1.6 Explosion hazards usually are accompanied by fire. Fixed fire fighting equipment like automatic sprinklers, if installed, shall be such that minimum damage is caused to it. B 3.1.7 Maximum pressure in a vent structure decreases with increase in the size of vent but is independent of rupture pressure of the diaphragm. ’ B 3.1.8 Unobstructed vent opening is the most effective pressure release vent structures. B3.1.9 Pressure required to rupture diaphragms of the vent areas and material varies directly with the thickness of the material. B3.1.10 The extent of venting required directly varies with the degree of explosion hazard. B 3.1.11 It has been established from experience that explosion from dusts, vapours and gases do not involve the entire column of the enclosures, rather concentrates in the upper and lower part of the explosion range. As a result such explosions are relatively weak compared to an optimum situation where the concentration of such matters spread all over the explosion range. B3.1.12 Unrestricted rectangular vents are equally effective as square vents of the same area. B3.1.13 The finer the dust particle size the more violent is the explosion for a given material. Due to very fast rise in ressure it is difficult to effectively vent such materials as aluminium powdes, hydrogen and acetylene. Flow burning dust in confined space may cause much damage because of longer duration of pressure. Some dusts may even react with some inert gases such as nitrogen and carbon dioxide and ignite. B3.2 Explosion relief vents may be provided with open or unobstructed vents, louvers, open roof vents, hanger e doors, building doors, windows, roof or wall panels or marble/fixed sash. Any or more than one of ese may be adopted depending on individual situations and requirements as decided by the Authority. B 3.2.1 Suction of external wind pressure shall be taken into consideration while designing and type of vents since wind pressure may reach up to 2 x 10° N/m? in severe wind storms. B 3.2.2 Selection of explosion relief vent for any occupancy shall be based on two considerations, safety to lives of inmates and minimum damage to property. B3.2.3. When large hanger type doors or metal curtain doors in sidewalls are used as vents it has to be ensured that they are open during operation of the related machinery or equipment. B3.2.4 Roof vents covered with weather hoods shall be as light as possible and attached lightly, so that it is easily blown off as and when an explosion occurs. B3.2.5 Doors and windows used as ee tanec vents shall be so fixed as to open outward. Doors shall be fitted with friction, spring or magnetic, latches that function automatically at the slight increase in internal pressure. B 3.2.6 Placed at the top or bottom, the hinged or projected movable sash shall be ng peeoon with latch or friction device to prevent accidental opening due to wind action or intrusion. Such latches or locks shall be well maintained. B 3.2.7 Fixed sash shall be set with light anchorage in the wall or when the anchorage is tight shall be fitted with plastic glazing in plastic putty. | B 3.2.8 In worst scenario or case where a whole building or an entire room is involved, it may be desirable to have the entire structure constructed with light wall and roof to collapse and thus prevent the worst effect of explosion. B3.4 Area requirement depend ordinarily on the expected maximum intensity or an explosion, the strength of the structure, the type of vent closure and other factors. B 3.4.1 Venting shall be so planned as to prevent injury to inmates and damage to enclosure. In populated locations, substantial ducts or diverts shall be provided to channelize the blast towards a pre-determined direction. B 3.4.2 When ducts are used, they shall be of such strength as to withstand the maximum expected explosion pressure.B3.4.3
B3.4.4
B3.4.5
B3.4.6
B3.4.7
B3.4.8
B3.4.9
B3.4.10
B3.4.11
B3.4.12
B3.4.13
B3.4.14
B3.4.15
B3.4.16
If explosion are probable within the duct, they shall be equipped with diaphragm to rupture at predetermined locations. The duct system shall not be physically connected to more than one collector. In large structures the location of vents shall be relative to the point of explosion as it may be very difficult to pinpoint location of explosion. Light, hinged scrounge type panels shall be preferred over diaphragm type in slow explosion involving coal dust, chlorinated solvents etc. Particularly in case of rapid explosion hazard, vent blocking or obstruction shall be meticulously avoided. Counter weights inducing inertia to vents shall be avoided. Venting devices actuated by detonators shall open at as low pressure as possible and shall be of light construction, so that full opening can be quickly achieved. Vents shall be so sized and designed as to prevent rupture of the protected device. Skylight with moveable sash that opens outward or fixed sash having panes of glass or plastic that blow out readily under pressure from within can be used to supplement wall vents or windows, provided their resistance to opening or displacement may be kept as low as possible consistent with structural requirement of the building. : Flexible plastic sheets in slotted frames may be used for vent closure in such manner as to budge and be relieved off the frame when subject pressure from within. This transparent or translucent plastic sheets that crack or rupture under less pressure than single strength glass are preferred materials for vent closure or window sash. For equivalent explosion pressure release, larger closed vents will be required compared to open vents. More generous venting shall be provided for small enclosures like that of a machine or equipment room based on the following considerations: | Vent opening per unit Volume of enclosure | Types of volumes of enclosures | Examples | Remarks | | :--- | :--- | :--- | :--- | | a) \text^2 / 0.3\text0.9\text^3 | Machines and ovens of light construction | | | b) \text^2 / 0.9\text^3 (typo in original print for ) | Fairly large enclosure \text700\text^3ii) \text^2 / 1.65\text2.25\text^3 | Large rooms or buildings over \text^3$
- Enclosure with heavy reinforced concrete walls
- Light reinforced concrete brick or wood construction
- Light weight construction, prefabricated panels | Small fraction of space of the large enclosure occupied by hazardous equipment/machinery | |
B3.4.15
B3.4.16
If explosion are probable within the duct, they shall be equipped with diaphragm to rupture at predetermined locations. The duct system shall not be physically connected to more than one collector. In large structures the location of vents shall be relative to the point of explosion as it may be very difficult to pinpoint location of explosion. Light, hinged scrounge type panels shall be preferred over diaphragm type in slow explosion involving coal dust, chlorinated solvents etc. Particularly in case of rapid explosion hazard, vent blocking or obstruction shall be meticulously avoided. Counter weights inducing inertia to vents shall be avoided. Venting devices actuated by detonators shall open at as low pressure as possible and shall be of light construction, so that full opening can be quickly achieved. Vents shall be so sized and designed as to prevent rupture of the protected device. Skylight with moveable sash that opens outward or fixed sash having panes of glass or plastic that blow out readily under pressure from within can be used to supplement wall vents or windows, provided their resistance to opening or displacement may be kept as low as possible consistent with structural requirement of the building. : Flexible plastic sheets in slotted frames may be used for vent closure in such manner as to budge and be relieved off the frame when subject pressure from within. This transparent or translucent plastic sheets that crack or rupture under less pressure than single strength glass are preferred materials for vent closure or window sash. For equivalent explosion pressure release, larger closed vents will be required compared to open vents. More generous venting shall be provided for small enclosures like that of a machine or equipment room based on the following considerations: Volume of enclosure enclosures. a) 100.cm*/0.3 to 0.9m mall enclosures of less achines and ovens 0 than 30m? light construction b) 100 cm*/0.9m mall enclosures More sturdy construc- tion having reasonably high bursting pressure ly Bi = R ¢) 100m*/0.9 to 1.5m: Bins, ilos, ooms | Important to try d) i) Remarks Storage tanks and predict point of origin of explo- sion in relation to vent location. ‘action of space o: the large enclosure occupied by hazardous equipment/machinery i) 100cm*/2.25 m over 700m? Enclosure with heavy reinforce concrete, walls Light reinforced concrete brick or wood construction Light weight construction, pre fabricated panels ii) 1000 cm2/1.65 to 2.25 m3 iii) 1000 cm*/1.5 to 1.65 m3 As far as possible hazardous areas shall be segregated be means of fire walls or party walls to prevent spread of fire. Use of tile or such other light construction materials shall not be permitted in hazardous locations because of its potential to cause injuries to inmates in case of explosion.APPENDIX C Detailed Guidelines for Selection and Siting of Fire Detection System
C1 GENERAL
This appendix provides a guideline for selection and siting of equipment for fire detection in buildings. Ley! CHOICE OF FIRE DETECTORS Fire detectors may respond to any one manifestations of combustions such as heat generation, smoke and flames. No single detector is able to meet the need of all types of fires and all t of occupancies. As such, based on needs arising out of various situations and occupancies, judicious selection is extremely important for the reduction of fire hazards. :C21 Heat Detectors
“Point” or “Spot” type detectors are actuated by heat at layer adjacent to it over a limited area. “Line” type detectors are sensitive to the effect produced by heated gas along any portion of the detector line. Both the types operate on two broad principles: one, the heat sensitive elements is actuated by temperature risin beyond a predetermined level; while the second system is actuated by predetermined rate of rise o} temperature.C22 . Smoke Detectors y
Three types of smoke detectors are commonly used. First type is actuated by absorption or scattering of visible or near-visible light by combustion product and known as “optical detector’. The second type is actuated by the production on ionization current within the detector and referred to as “ionization detector”. The third type is sensitive to carbon monoxide or other products of combustion and is known as “chemically sensitive detector”.C23 Flame Detectors
Flame detectors are sensitive to radiation emitted by flames.C3 APPLICATION
Since both heat, smoke and flame are produced during a fire, detectors responding to all these are accepted as general purpose detectors. C31 Fixed temperature heat detectors are suitable for use where ambient temperatures are high and or may rise and fall rapidly over a short period.C3.2 Rate of Rise Heat Detectors
These are suitable for use where ambient temperatures are low and/or may rise over a wide range slowly. Abnormally sharp rise in temperature during a fire actuates this alarm. ts such it cannot be used with confidence where ambient temperatures reaches in the neighborhood of 40°C, but are best used where ambient temperatures are in the range of about 40°C.C33 Smoke Detectors
In general, these should be used at places where ambient temperature varies between 0° to 35°C.C3.4 Optical Smoke Detectors
Invisible smoke from a clear burning shall not actuate the such detectors. But they respond quickly where smoke is optically dense and as such suitable for use in dust free clean atmosphere. Over a period of time, due to dust and dirt, the sensitive surface of photo sensitive element and Dor executor aap of optical detectors may loose its efficiency and as such optical detectors should be cleaned and maintaine pels aC3.5 Ionization Chamber Smoke Detector
These respond: quickly to invisible smoke of clear burning, but may not respond to fire producing dense smoke. These can be used in dust free, humidity controlled area. Smoke and other fumes, dust including slow accumulated and disturbed aerial dust, fibre, steam and condensation produced by normal processes and vehicle engines may, cause false alarm. Warehouses exposed to fast air flows can also cause false alarm. Burning of polyvinyl chloride will not sensitize the detector in time and may provide late warning or no warning at all.C3.6 Chemically Sensitive Smoke Detectors
Chemically coated sensitive elements react to carbon monoxide or other products of combustion present in smoke. Dust or moisture adversely affects the sensitive elements and are not very suitable for residential | use. C3.7 Smoke detectors are not naturally suitable in places where the production process produces smokes. Other suitable types need to be used.C3.8
C4
C41
C42
C43
C44
C45
C46
C47
csC6
C61
C62
C63
C64
C65
C66
C67
C68
Application of flame detectors are restricted due to the fact that all combustions do not necessarily accompany flame and that clear line of sight is desirable as radiation from flames travel in straight lines for actuation of sensitive element. As supplement to heat and smoke detectors, flame detectors may be used. SITING OF DETECTORS Every portion of building should be covered and all effectively enclosed spaces should be considered separately based on the limits of spacing for types of detectors concerned. Rooms divided into sections by walls, partitions or storage racks, as in libraries and archives, arching up to 300 mm to the ceiling or goods stacked in defined areas shall have detectors for each section of passageway. Hoist, elevators and similar openings, windows, doors, ventilators and inlet ducts of an air-conditioning system shall be covered by detector within 1.5 m at the top for every 2 m of their width or part thereof. Detectors shall be installed at the centre of each inlet to the return duct of an air-conditioning system. Detectors shall be installed 2 m apart if the inlet is continuous or oblong. Staircases shall be covered by detectors on each floor, and all lantern lights shall be covered by detectors. Specie of detectors shall be reduced up to 75 per cent from the standard spacing in case of ceilings with waffle having depth between 200 and 500 mm and up to 50 per cent with depths above 500 mm. Where detectors are installed in the ridges of the waffle, each waffle shall be treated as an independent compartment. Ceiling intersected by beams more than 250 mm in depth, each | shall be considered as separate compartment and detectors shall be installed considering each bay an independent compartment. HEIGHT CONSIDERATION Coverage provided by the sensitive detectors fall sharply as the height above floor level increases, generally, where roof height exceeds 9 m, heat sensitive detectors become ineffective. SITING OF THE SENSITIVE DETECTORS (POINT OR SPOT TYPE) Distance from Ceiling When positioned, heat sensitive elements shall be placed between 25 and 150 mm from the ceiling or underside of roof. Spacing of Detectors Depends on probable hazards in relation to occupancy and shall have to be approved by the fire authority. When ceiling are crossed by beams, girders or other structural elements of 250 mm or more in depth to form compartments, detectors shall be placed in each compartment. Single Truss and North Light Roofs One row of detectors shall be sited along the apex of each roof or bay. Space of this row of detectors and other detectors headed to cover the area shall be determined from the designed requirement and approved by the authority. Floor Opening At least one detector shall be suitably positioned within 1.5 m of hoists, elevators, stairways, wall holes and similar openings to the floor above. Lantern Lights Fixed temperature type detectors shall be used in lantern which shall be protected from direct sun light as the combination of solar and internal heating cause rapid temperature variation. Heated Areas within Building Only fixed temperature type detectors shall be used in areas like kitchen, boiler room, furnace, room etc. where sudden temperature rise may take place. If ambient temperature is likely to exceed 40°C, detector’s nominal operating temperature may need to be increased. However the maximum operating temperature setting should not exceed 117°C. Vibration and Rapid Temperature Change Detectors covering hoist apertures may be subject to vibration and may experience rapid temperature change and thus shall be fitted with fixed temperature fusible alloy fuses. ‘C8 SITING OF SMOKE SENSITIVE DETECTORS
C8.1 Once on fire, a building accumulates the greatest concentration of visible and invisible smoke at the highest points of enclosed areas. Smoke detectors are usually sited here. The detectors shall be as mounted as to place the sensing elements between 25 and 100 mm from the underside of roof. C8.2 Area coverage by individual detectors are same as that of heat detectors but the maximum distance between two detectors may be 20 per cent more than that recommended for heat detectors. Actual spacing depends on airflow pattern in protected area. C8.3 Area coverage of smoke detectors is dependent on many factors. The following aspects shall be taken into considerations in the design of detectors. a) When a big room or space to be protected is divided into section by walls, partition or storage racks including book stacks in libraries and archives, each section or passageway shall be protected separately. Additional rows of detectors shall be provided at the rate of one per 2 metre or part thereof. The detectors being not more than 3m apart in each row, shall be staggered. b) Any area of a building provided with mechanical ventilation system results in more than 10 air changes per hours, which causes dilution of smoke and a definite air flow pattern is established. In such cases ventilation inlet and exhaust openings shall be covered by additional detectors. c) Additional detectors may become necessary to cover smaller extract ducts, windows, ventilations and other openings. In rooms with high rate of air change, additional detectors may be necessary to cope with air flow pattern and dilution of combustion product. d) Detectors shall be installed within 1.5 m of duct to monitor inlet duct. e) Detector shall be installed in the centre of inlet of return air duct. Where place above the false ceiling is used as return air duct, the opening to return air shall have a detector every 2 m or part thereof of its length within 250 mm of the opening. f) In most buildings mechanical ventilation do not run continuously. The detectors shall, thus, be so sited as to detect fire irrespective of mechanical ventilators are in operation or not. g) Warm air naturally concentrates under ceiling and in the apex of pitched roofs. Sometimes this warm air creates what is known as heat barrier acting as an effective barrier to the products of combustion. This results in small fire producing little or no appreciable change in ambulant environment. The combustion products from such a fire will spread out below the heat barrier in the same way as they do beneath the ceiling or an apex of a pitched roof. Siting of detectors should be arranged to take this into account. h) Factors capable of establishing temporary or permanent effects on detector’s siting shall be borne in mind while designing the system and include the following: i) Various forms of overhead heating ii) Exhaust air from air cooling equipment blowing out into the room or factory area iii) Deep beams iv) Roofs and ceiling of unusual shape v) Building with ground areas above 10 m and up to 30 m in height vi) Staircases vii) Canteen and Restaurants viii) Plant Rooms ix) Ambulant air currentsAppendix D Special Requirements of Buildings more than 20 Metre High
D1 GENERAL
This appendix specifies the special requirements for the fire protection in buildings more than 20 m in height.D2 CONSTRUCTION
D2.1 Construction of all load bearing components like stairways, corridors and facades shall be of noncombustible materials. D2.2 Internal staircase walls shall be made of bricks or reinforced concrete with a minimum of 2 hour fire rating. D2.3 The crown and landings of a staircase shall be ventilated to atmosphere with 0.5 m² openings in the external walls and crown. Because of difficult location or other compelling reasons, if it becomes impossible to ventilate the staircase, a positive pressure of 50 pa shall be maintained inside the staircase by any mechanical means. Pressure sensitive Automatic Fire Alarm System shall be installed in the staircase. Stair roof shall be 1 m above the surrounding roof level. Use of glazing or fire bricks in the stair shall not be permitted. D2.4 Materials used for inner finish shall be restricted to Class I rating of flame spreadability.D3 LIFTS
Lifts installed in tall buildings shall comply with the following requirements over and above those listed under Chapter 5, Part 8. D3.1 Walls enclosing the lift core shall have a fire resistance rating of 2 hours. Lift shaft shall have a top vent area of not less than 0.2 m². D3.2 The room containing the motor operating the lift shall preferably be placed at the roof of the lift core and shall be separated from the rest of the lift core by a floor wall having same fire rating as that of the lift core walls. D3.3 Landing doors in lift core shall have at least half an hour fire resistance rating. D3.4 Not more than 4 independent lifts can be assembled together in one liftbank core and the core walls of individual lifts shall have a fire resistance rating of at least 2 hour. D3.5 Lift car doors shall have a fire resistance rating of at least 1 hour. D3.6 For lift in tall buildings above 20 m in height, collapsible gates shall not be permitted. Instead solid doors of fire resistance rating equal to that of Sec K 3.5 shall be installed. D3.7 When lifts are located in a central core location of building, exits from lift lobby shall be through a self closing smoke door of half an hour fire resistance. D3.8 Lifts shall not normally serve the basement. D3.9 Ground switch of the lifts hall be provided at ground floor level so that fire personnel can bring the lifts to ground level at the time of emergency. D3.10 Telephone or other voice communications facilities may be provided in lifts installed in buildings of 26m or more in height. The communication system, in such cases shall be connected to ground command station. D3.11 Appropriate slope in floor shall be provided to avoid water entering the lift shaft during fire fighting. D3.12 Suitable signs shall be erected and maintained at appropriate positions on all floors of a highrise building showing the floor plan and exit stairways. Cautions regarding use of lifts during a fire shall be inscribed in the signs.D4 FIRE LIFTS
One or more lifts shall be exclusively designed and maintained for the use of firemen is case of emergency. D4.1 The lifts shall be so designed and maintained as to be able to reach upper floors and are directly accessible to every dwelling or lettable floor space on each floor by fire personnel. D4.2 The lift or lifts shall have a load carrying capacity of 545 kg (8 persons) with a minimum floor area of 1.4 m² and auto close doors. D4.3 Power supply of the fire lift shall be separated from the main source supplying the building. D4.4 In case of power failure from normal supply, it shall be so designed as to trip automatically to alternate supply of power. In tall apartment complexes such tripover could be accomplished by manually operated changeover switch. Other alternative could be an electric wiring which shall be so designed as to bring the lift car to ground level with door open in case of power failure. D4.5 Fire lifts shall be operated on a two-button switch system. Two button switch is placed adjacent to the lift at floor level and kept in a glass covered box. When the switch is on landing call points become inoperative and the lift is controlled from the car. When the switch is off the lift returns automatically to normal operation and can be used by occupants at normal times. D4.6 On landing doors at each floor, the sign “FIRE LIFT” shall be painted conspicuously in such sizes as to be easily noticeable by occupants or users of the lift. D4.7 Irrespective of height lift speed shall be such as to reach the top floor from ground level in 1 minute.D5 SERVICE DUCTS
If there is any service duct, they shall comply with the following provisions. D5.1 Services ducts, if any, shall be enclosed by a 2 hour rated fire walls and doors. Ducts having area more than 1 m² shall be closed at each floor level except the passage of pipes etc. across the floors. The passage gaps of pipes, cables etc. shall be suitably sealed. D5.2 A vent opening at the crown of the service shaft shall be provided with an opening, the size of which shall be between 25 and 50 per cent of the duct area. D5.3 Air-conditioning or other service shafts shall be located as far away as possible from the exits of a building.D6 REFUSE CHUTES
Refuse chutes shall be enclosed by wall of fire resistance rating of at least 2 hours and shall extend at least 1 m above roof level and shall be vented to atmosphere. Chutes in no case shall be located within the staircase enclosure. Inspection panels and doors to refuse chutes shall be at least 1 hours fire resistance rating.D7 REFUSE AREA
Except multi-family dwelling, all other buildings shall incorporate provision of refuge area on the external walls as cantilever projection or any other suitable manner. Refuge area shall not be less than 15 m² at the heights mentioned below: a) Floors between 20 and 26m: One refuge area on the floor immediately above 20 m. b) Floors above 26 m: One refuge area on the floor immediately above 26 m and then one refuge area per five floor above 26 m.D8 BASEMENTS
Each basement shall be independently ventilated. Venting shall be achieved by grills, breakable stall board lights or pavement lights or by way of shafts of aggregates having cross-sectional area of not less than 2.5 per cent of floor area spread evenly around the perimeter of the basement. Alternatively air flow inlet at floor level and smoke outlet at ceiling level may be provided. Inlets and extracts may be terminated at ground level with stall boards and pavement light, but ducts for conveyance of fresh air to floor shall have to be laid. Stall boards and pavement lights shall be so positioned as to be easily accessible by fire brigade personnel. D8.1 Basement staircase shall be encased and placed near the outer edge of the basement with materials of 2 hours fire resistance. The stair shall be entered at the ground level from open air so that the smoke from a fire in the basement shall not obstruct any exit serving the ground and upper floors. Communication with the basement in case of emergency shall be maintained through a lobby provided with a fire resisting self closing door of 1 hour fire resistance. Additional staircases shall be provided at appropriate locations if travel distance exceeds 20 m. D8.2 Single intake duct may serve all the floors of a multi-storey basement, but separate smoke outlet duct or ducts shall be provided for each basement or basement compartment. D8.3 For lower basement floors, mechanical extractors for smoke venting shall be provided. The system shall operate automatically by heat sensitive elements or sprinklers. Devices with manual operation may also be installed. The following features shall also be considered. a) Ventilating ducts shall be constructed with the brick masonry or cement concrete work as far as possible. Fire dampers shall be provided when these ducts cross the transformer or electrical switch board areas. b) Kitchen using gas, departmental stores and shops shall not be allowed to operate in basement or sub-basement. c) Openable windows on external walls shall be fitted with such locks which can be opened by fire man axe. d) Floor area exceeding 750 m² shall be compartmented by fire partition walls having 2 hours fire rating. Floor areas provided with sprinklers may be increased by 50 per cent. In long buildings distance between fire walls shall not exceed 40 m.D9 BUILDING SERVICES
Building services in tall buildings shall comply with the following provisions. D9.1 Air-conditioning shall conform to the following: a) Escape passageways like staircases, common corridors, lift lobbies shall not be used as return air passage. b) Gauge metal of thickness and quality approved by the authority shall only be used in ducting. c) Openings exerted by the passage of ducts across fire walls or floors shall be properly sealed with fire resisting materials like vermiculite concrete or asbestos fibre materials. d) Duct insulation (inside and outside) materials shall be of noncombustible nature (such as glasswool) which shall not be wrapped or secured around the duct by any material of combustible nature. e) Metallic ducts shall be used as far as possible instead of using the space above false ceiling as return air passage. f) Floor areas more than 750m² shall be partitioned for isolation by fire walls and automatic fire dampers. g) Air ducts serving main floor areas and corridors shall not pass through the staircase enclosure. h) Air handling units and ducts shall be independent for each floor and there shall be no interconnection of ducts between floors. i) In case of air handling units serving more than one floor, the system shall comply with the following provisions, in addition to the conditions mentioned above.- Individual floors shall be isolated from the main riser by incorporating automatic fire dampers working on fusible link.
- Respective air handling units of air-conditioning system shall automatically be switched off as soon as the automatic fire alarm become active. j) Treated fresh air conveyance through the vertical shaft shall be of masonry construction. k) Ceiling and its fixtures shall be of noncombustible materials when these will be used as return air passage. l) The air filters of the air handling units shall be of noncombustible materials. m) Air handling equipment room shall not store any combustible material. n) To have access to main fire dampers and for cleaning the duct of accumulated dusts, the main air duct trunk shall be fitted with appropriate inspection panels of tight fitting nature.
- At the fire separation wall,
- Where ducts or passages entre the central vertical shaft,
- Where the ducts pass through floors, and
- At the inlet of supply air ducts and the return air duct of each compartment in every floor.