Quick Reference-Fire Fighting (Part-1)


 

Class of Fire

CLASS Type of Fire Type of Fire Extinguisher
Class A Fires involving Paper, Wood, Textile, Packing materials and the like. Water, foam, ABC dry power and halocarbons.
Class B Fires involving Oil, Petrol, Solvent, Grease, Paints, Celluloid and the like. Foam, dry powder, clean agent and carbon dioxide extinguishers
Class C Fires involving Electrical Hazards, Motor Vehicle Gaseous substance under pressure. Dry powder, clean agent and carbon dioxide extinguishers
Class D Fires involving Chemicals, Metal and active like

Magnesium ,titanium

Extinguishers with special dry powder for metal tires

 

Area covered by Fire Extinguisher (NBC)

Type of Fire Extinguishers Coverage (Floor) Area
Water/ Sand Bucket 100 sq.mt.
Sprinklers 6 sq.mt.
Extinguishers (9 Liter) 600 sq.mt.
Heat Detectors 16 sq.mt.
Hydrant Riser (Outlet 100 mm dia with landing valve and First aid hose reel) 930 sq.mt
Smoke Detectors 50 sq.mt.

 

Water Requirement for the Fire Fighting (AS per NBC)

Q = 3000 P
Q = Fire demand in Liters/Minutes
P = Population in Thousands
Note:  The above rate must be maintained at a minimum pressure of 1 to 1.5 kg / cm2 for at least four hours.

 

Water Requirement for Wet Riser/Down Corner System (As per NBC -TABLE 4)

Residential Buildings U.G. Water Storage Tank Static Terrace Tank
15 m to 30 m 50,000 lts 10,000 lts
30 m to 45 m 1,00,000 lts 20,000 lts
Above 45 m 2,00,000 lts 40,000 lts

 

Water Requirement for Wet Riser/Down Corner System (As per NBC -TABLE 5)

Business Building U.G. Water Storage Tank Static Terrace Tank
15 m to 30 m 100000 lts (50000 lts if covered area in G.F is less than 300sq.m.) 20,000 lts
30 m to 45 m 20000 lts 20,000 lts
Above 45 m 250000 lts 50,000 lts

 

Classification of fire Pumps (As per IS 15301)

Pump Size Location of Pump Installation
450 Liter/Min Pumps to be installed on the terrace to feed the Down Comer System.
900 Liter/Min Pumps to be installed on the terrace to feed the Down Comer System.
2280 Liter/Min Pumps are to be housed in the pump house.
2850 Liter/Min Pumps are to be housed in the pump house.
4500 Liter/Min Pumps are to be housed in the pump house.
For special risks 6700 Liter/Min Pumps are to be housed in the pump house.

 

Suction and Delivery Pipe Sizes (IS 3844)

Pump Size Pump Location Suction Delivery
450 Liter/min Terrace 50 mm 50 mm
 900 Liter/min Terrace 75 mm 50 mm
1400 Liter/min Terrace 100 mm 100 mm
2280 Liter/min Fire Pump 150 mm 150 mm
2850 Liter/min Fire Pump 200 mm 150 mm
4500 Liter/min Fire Pump 250 mm 200 mm
6700 Liter/min Fire Pump 250 mm 200 mm

 

Different Types of Fire Extinguishers for Different Classes of Fires ( IS 2190 )

Type of Extinguisher IS Type of Fires
Class A Class B Class C Class D
water type (gas cartridge) IS 940 , IS 13385 S NS NS NS
water type (stored pressure) IS 6234 S NS NS NS
mechanical foam type (gas cartridge) IS 10204, IS 13386 S S NS NS
mechanical foam type (stored pressure)  IS 14951,IS 15397 S S NS NS
dry powder type (stored pressure)  IS 13849 S S S NS
dry powder type (gas cartridge)  IS 2171 , IS 10658 S S S NS
dry powder type for metal fires  IS 11833 NS NS NS S
carbon dioxide type  IS 2878, IS 8149 NS S S NS
clean agent gas type  IS 15683 S S S NS
halon 1211 type IS 4862 , IS 11108 S S S NS

 

PRESSURE TESTING OF FIRE EXTINGUISHERS  ( IS 2190 )

Type of Extinguisher IS Test Interval (Year) Test Pressure (kg/cm2) Pressure Maintained for Min. (kg/cm2)
Water type (gas cartridge) IS 940 3 35 2.5
Water type (stored pressure)  IS 6234 3 35 2.5
Water type (gas cartridge) IS 13385 3 35 2.5
Mechanical foam type (gas cartridge)  IS 10204 3 35 2.5
Mechanical foam type (stored pressure) IS 15397 3 35 2.5
Mechanical foam type (gas cartridge)  IS 13386 3 35 2.5
Mechanical foam type (gas cartridge) 135 liter  IS 14951 3 35 2.5
Dry powder ( stored pressure) IS l3849 3 35 2.5
 Carbon dioxide IS 2878 5 250 2.5
 Clean agent IS 15683 3 35 2.5
Dry powder (gas cartridge) IS2171, IS10658 3 35 2.5

 

LIFE OF FIRE EXTINGUISHERS ( IS 2190)

Type of Extinguisher Life Time, Year
Water type 10
Foam type 10
Powder type 10
Carbon dioxide 15
Clean agent 10

 

RECOMMENDATIONS FOR INSTALLATION OF FIRE EXTINGUISHERS  ( IS 2190 )

Occupancy Type of Occupancy Nature of Occupancy Class of
Fire
Typical Examples
Group A Residential buildings Low Hazard CLASS A Lodging or rooming, one or two family houses, private dwellings, dormitories, apartment houses, flats, up to 4 star hotels, etc
  Low Hazard CLASS C Small kitchens having LPG connection, electrical heaters, etc
  Medium Hazard CLASS A Multi-storied buildings, multi-risk buildings, five star hotels, etc
Group B Educational buildings Low Hazard CLASS A Tutorials, vocational training institutes, evening colleges, commercial institutes
  Medium Hazard CLASS A Schools, colleges, etc
Group C Institutional buildings Medium Hazard CLASS A Hospitals, sanatoria, homes for aged, orphanage jails, etc
Group D Assembly buildings-D-1 High Hazard CLASS A Theatres, assembly halls, exhibition halls, museums, restaurants places of worship, club rooms, dance halls, etc, having seating capacity of over 1 00 persons
Assembly buildings-D-2 High Hazard CLASS A Theatres, assembly halls, exhibitions halls, museums, restaurants, places of worship, club rooms, dance halls, etc, having seating capacity less than 1 000 persons
Assembly buildings-D-3 High Hazard CLASS A Theatres, assembly halls, exhibition halls, museums, restaurants, places of worship, club rooms, dance halls, etc, but having accommodation for more than 300 persons, but less than 1 000 persons, with no permanent seating arrangement
Assembly buildings-D-4 / D5 Low Hazard CLASS A Theatres, assembly halls, exhibition halls, museums, restaurants, places of worship, club rooms, dance halls, etc, but having accommodation less than 300 and those not covered under D-l to D-3
Group E Business buildings-E-1 Special Hazard CLASS A Offices, banks, record rooms, archives, libraries, data processing centers, etc
Business buildings-E-2 Medium Hazard CLASS B Laboratories, research establishment, test houses, etc
Business buildings-E-3 Special Hazard CLASS A Computer installations
Group F Mercantile buildings Medium Hazard CLASS A Shops, stores, markets, departmental stores,
underground shopping centers, etc
Group G Industrial buildings Low Hazard CLASS A Small industrial units
Medium Hazard CLASS A Corrugated carton manufacturing units, paper cane units, packing case manufacturing units, cotton waste manufacturing units
HH CLASS A Large number yards, saw mills, godowns and warehouses storing combustible materials, cold storages, freight depots, etc
Low Hazard CLASS B Demonstration chemical plants, small chemical processing plants, pilot plants, etc
Medium Hazard CLASS B Workshops, painting shops, large kitchens, industrial canteens, generator rooms, heat treatment shops, tread rubber manufacturing units, petrol bunks, tubes and Haps units, etc
High Hazard CLASS B Petroleum processing units, chemical plants, industrial alcohol plants, effluent treatment plants, etc
High Hazard CLASS C Fertilizer plants, petrochemical plants, LPG bottling plants, etc
High Hazard CLASS D All processes involving use of combustible highly flammable materials, reactive metals and alloys, including their storage
Group H Storage buildings Medium Hazard CLASS B Flammable liquid stores, storage in drums and cans in open, paints and varnishes go down
High Hazard CLASS B Tank farms, chemical and petroleum bulk storage depots, large service stations, truck and marine terminals, underground LDO/furnace oil storage yards, etc
Medium Hazard CLASS C LPG distribution godown/office, distribution storage godowns/offices of D, N, H, Argon and other industrial gases
High Hazard CLASS C Storage and handling of gas cylinders in bulk, gas plant, gas holders ( Horton), spheres, etc
Group J Hazardous Buildings used for storage, handling, manufacture and processing of highly combustible explosive materials. (Risks involved in terms of class of fire and intensity of fire has to be assessed on case to case basis and statutory authorities to be consulted, environmental factors and mutual aid facilities to be taken into account before deciding on the fire extinguisher requirements.)

 

RECOMMENDED  EQUIPMENT TO BE INSTALLED ( IS 2190 )

Class of Fire  Occupancy No of Fire Systems
CLASS A Low Hazard One 9 liter water expelling extinguisher or ABC 5 kg/6 kg fire extinguisher, for every 200 m2 of floor area or part thereof with minimum of two extinguishers per compartment or floor of the building.
Medium Hazard Two 9 liter water expelling extinguishers or ABC 5 kg / 6 kg fire extinguisher, for every 200 m2 with minimum of 4 extinguishers per compartment floor.
Medium Hazard Provision as per MH occupancy; in addition to one 50 liter water CO2/25 kg ABC fire extinguisher for every 100 m2 of floor area
Special Hazard One 4.5 kg capacity carbon dioxide or one 2/3 kg capacity clean agent extinguisher for every 100 m2 of floor area or part thereof with minimum of two extinguishers
CLASS B Low Hazard One 9 liter foam extinguisher, mechanical or BC or ABC, 5 kg/6 kg fire extinguisher, for every 200 m2 of floor area or part thereof with minimum of two extinguishers per compartment or floor.
Medium Hazard Two 9 liter foam extinguisher, mechanical type, or 5/6 kg dry powder extinguisher ( or one of each type) for every 200 m2 area with minimum of four extinguisher per compartment
Medium Hazard Provision as per MH, and in addition to one 50 liter mechanical foam type extinguisher or 25 kg BC fire extinguisher for every 100 m2 or part thereof one l35 liter foam mechanical extinguisher for every 300 m2 of floor area
CLASS C Low Hazard One 2/3 kg dry powder of clean agent extinguisher for every 20 m2 of floor area
Medium Hazard One 10 kg dry powder extinguisher (stored pressure) or 6.5 kg  carbon dioxide extinguisher or 5 kg clean agent for 100 m2 of floor area or part thereof, with minimum of one extinguishers of the same type for every compartment;
High Hazard Dry powder extinguisher (stored pressure) of 10 kg or 6.5 kg CO2 extinguisher, or 5 kg clean agent extinguisher for every 100 m2 of floor area or part thereof, subject to a minimum of two extinguishers of same type per room or compartment.
CLASS D High Hazard One 10 kg dry powder extinguisher with special dry powder for metal fires for every 100 m2 of floor area or part thereof with minimum of two extinguishers per compartment/room

 

Electrical Thumb Rule- High Rise Building (As per NBC)


 

Luminous Efficacy, Life, Lumen Maintenance and Color Rendition (Table-8) NBC
Light Source  Wattage Efficacy (lm/W ) Average Life Maintenance Color Rendition
Incandescent lamps  15 to 200  12 to 20  500 to 1000  Fair to good  Very good
Tungsten halogen     300 to 1500  20 to 27  200 to 2000  Good to very good  Very good
Standard fluorescent lamps       20 to 80 55 to 65 5000 Fair to good  Good
Compact fluorescent lamps (CFL)       5 to 40  60 to 70 7500 Good Good to very good
Slim line fluorescent      18 to 58 57 to 67 5000  Fair to good Good
High pressure mercury vapor lamps      60 to 1000  50 to 65 5000  Very low to fair  Federate
Blended – light lamps    160 to 250  20 to 30 5000 Low to fair  Federate
High pressure sodium vapor lamps  50 to 1000  90 to 125  10000 to 15000  Fair to good  Low to good
Metal halide lamps       35 to 2000  80 to 95 4000 to 10000 Very low  Very good
Low pressure sodium       10 to 180 100 to 200 10000 to 20000 Good to very good  Poor
LED  0.5 to 2.0  60 to 100  10000 Very good  Good for white LED

 

Approximate Cable Current Capacity

Cable Size Current Capacity MCB Size
1.5 Sq.mm 7.5 To 16 A 8A
2.5 Sq.mm 16 To 22 A 15A
4 Sq.mm 22 To 30 A 20A
6 Sq.mm 39 To 39 A 30A
10 Sq.mm 39 To 54A 40A
16 Sq.mm 54 To 72A 60A
25 Sq.mm 72 To 93A 80A
50 Sq.mm 117 To 147A 125A
70 Sq.mm 147 To 180A 150A
95 Sq.mm 180 To 216A 200A
120 Sq.mm 216 To 250A 225A
150 Sq.mm 250 To 287A 275A
185 Sq.mm 287 To 334A 300A
240 Sq.mm 334 To 400A 350A

 

Requirements  for  Physical  Protection  of Underground Cables  (As per NBC)

Protective  Element Specifications
Bricks  (a) 100 mm minimum  width 
(b) 25 mm thick 
(c) sand cushioning 100  mm  and  sand  cover 100 mm 
Concrete slabs At least 50 mm thick
Plastic  slabs (polymeric cover  strips) Fiber  reinforced plastic depending on properties  and has to be matched with the protective cushioning and cover
PVC  conduit  or  PVC  pipe  or stoneware  pipe or Hume pipe The  pipe  diameter should  be  such  so  that the  cable  is  able  to easily slip down the pipe
Galvanized pipe  The  pipe  diameter should  be  such  so  that the  cable  is  able  to easily slip down the pipe
The trench shall be back filled to cover the cable initially by 200 mm of sand fill; and then a plastic marker strip  hall be put over the full length of cable in the trench.
The marker signs shall be provided where any cable enters or leaves a building. This will identify that there is a cable located underground near the building.
 The trench shall then be completely filled. If the cables rise above ground to enter a building or other structure, a mechanical protection such as a GI pipe or PVC pipe for the cable from the trench depth to a height of 2.0 m above ground shall be provided.

 

AREA REQUIRED FOR GENERATOR IN ELECTRIC SUBSTATION (As per NBC)

Capacity  kVA Area m2 Clear Height below the Soffit of the Beam m
25 56 3.6
48 56 3.6
100 65 3.6
150 72 3.6
248 100 4.2
350 100 4.2
480 100 4.2
600 110 4.6
800 120 4.6
1010 120 6.5
1250 120 6.5
1600 150 6.5
2000 150 6.5

 

Low Voltage Cabeling for Building (As per NBC)

Low Voltage Cable Cables/wires, such as fiber optic cable, co-axial cable, etc. These shall be laid at least at a distance of 300 mm from any power wire or cable. The distance may be reduced only by using completely closed earthed metal trucking with metal separations for various kind of cable. Special care shall be taken to ensure that the conduit runs and wiring are laid properly for low voltage signal to flow through it.
The power cable and the signal or data cable may run together under floor and near the equipment. However, separation may be required from the insulation aspect, if the signal cable is running close to an un-insulated conductor carrying power at high voltage. All types of signal cables are required to have insulation level for withstanding 2 kV impulse voltages even if they are meant for service at low voltage.
Conduit Color Scheme Power conduit=Black
Security conduit=Blue
Fire alarm conduit=Red
Low voltage conduit=Brown
UPS conduit Green

 

Sub Station Guideline (As per NBC)

Substation Location Location of substation in the basement should be avoided, as far as possible.
If there is only one basement in a building, the substation/switch room shall not be provided in the basement and the floor level of the substation shall not be lowest point of the basement.
Substation shall not be located immediately above or below plumbing water tanks or sewage treatment plant (STP) water tanks at the same location
Substation Door/Shutter All door openings from substation, electrical rooms, etc, should open outwards
Vertical shutters (like rolling shutters) may also be acceptable provided they are combined with a single leaf door opening outwards for exit in case of emergency
For large substation room/electrical  room  having  multiple equipment,  two  or more  doors  shall  be provided which shall be remotely located from each other
No services or ventilation shafts shall open into substation or switch room unless specific to substation or switch room
Transformer Location In case of HV panel and transformers located at different floors or at a distance more than 20 m, HV isolator shall be  provided  at transformer end
In case transformer and main MV/LV panel room are located at different floors or are at a distance more than 20 m, MV/LV isolator shall be provided at  transformer  end
In  case  of  two  transformers  (dry  type  or transformers with oil quantity less than 2 000 liter)  located  next  to  each  other without intermittent wall, the distance between the two shall  be minimum  1 500 mm  for  11  kV, minimum 2 000 mm for 22 kV and minimum 2 500 mm for 33 kV. Beyond 33 kV, two transformers shall be separated by baffle wall of 4 h fire rating.
If dry type transformer is used, it may be located adjacent to medium voltage switchgear in the form of unit type substation. In such a case, no separate room or fire barrier for the transformer is required either between transformers or between transformer and the switchgear, thereby decreasing the room space requirement; however, minimum distances as specified.
Oil Filled Equipment (Transformer / C.B) Substations with oil-filled equipment/apparatus transformers and high voltage panels shall be either located in open or in a utility building
They shall not be located in any floor other than the ground floor or the first basement of a utility building  not be located below first basement slab of utility building.
They shall have direct access from outside the building for operation and maintenance of the equipment.
It shall be separated from the adjoining buildings including the main building by at least 6 m clear distance to allow passage of fire tender between the substation/utility building and adjoining building/main building.
Substation equipment having more than 2 000 liter of oil whether located indoors in the utility building or outdoors shall have  baffle walls  of  4  h  fire  rating between apparatus.
Provision of  suitable oil soak-pit, and where use of more than 9 000 liter of oil in any one oil tank, receptacle or chamber is involved, provision shall be made for the draining away or removal of any oil which may leak or escape from the tank, receptacle or chamber containing the same
Power Supply Voltage supply  is  at  240  V  single  phase  up  to  5  kVA, 415/240 V 3-phase from 5 kVA to 100 kVA, 11 kV (or 22 kV) for loads up to 5 MVA and 33 kV or 66 kV for consumers of connected load or contract demand more than 5 MVA.
In case of connected load of 100 kVA and above, the relative advantage of high voltage three-phase supply should be considered.
In case of single point high voltage metering, energy meters shall  be  installed  in  building  premise,such a place which is readily accessible to the owner/operator of the building and the Authority. The supplier or owner of the installation shall provide at the point of commencement of supply a suitable isolating device fixed in a conspicuous position at not more than 1.7 m above the ground so as to completely isolate the supply to the building in case of emergency
Trench Drain In case of cable trench in substation/HV switch room/MV switch room, the same shall be adequately drained to ensure no water is stagnated at any time with live cables.

 

Fence for Substation Enclose any part of the substation which is open to the air, with a fence (earthed efficiently at both ends) or wall not less than 1800 mm (preferably not less than 2400 mm) in height

 

HV Distribution in Building The power supply HV cables voltage shall not be more than 12 kV and a separate dedicated and  fire  compartmented  shaft  should  be provided for carrying such high voltage cables to upper floors in a building. These shall not be mixed with any other shaft and suitable fire detection and suppression measures shall be provided throughout the length of the cable on each floor.

 

Switch Room / MV switch room Switch room / MV switch room shall be arrived at considering 1200 mm clearance requirement from top of the equipment to the below of the soffit of the beam .In case cable entry/exit is from above the  equipment  (transformer,  HV switchgear, MV  switchgear),  height  of substation room/HV switch room/MV switch room shall also take into account requirement of space for turning radius of cable above the equipment height.

 

 

 

 

 

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