This document compares the classification systems and requirements for fire protection systems between the TAC and OISD 116 rules. Some key differences include: - TAC classifies occupancies as light, ordinary, or high hazard while OISD 116 uses sub-categories A and B. - OISD 116 has additional requirements for dry chemical powder extinguishers of larger capacities and the placement of at least one extinguisher every 750 sqm. - For hydrants, TAC requires spacing of every 30m for high hazard risks while OISD 116 requires a minimum of 15m from protected equipment and locations along roadsides for easy accessibility. - OISD 116 has additional requirements for

1. COMPARISION BETWEEN TAC AND OISD 116 RULES
TAC OISD 116
CLASSIFICATIONS OF OCCUPANCIES –(As given in F P Manual)
• LIGHT HAZARD OCCUPANCIES:
• ORDINARY HAZARD OCCUPANCIES:
• HIGH HAZARD OCCUPANCIES:
SUB-CATEGORY (A) SUB-CATEGORY (B).
HAND APPLIANCES SHALL BEAR ISI CERTIFICATION
MARK.
Only meant for attacking small fires in their incipient stages
and are not intended to deal with large outbreaks of fires.
one 9-litre water type extinguisher or 5 kg DCP extinguisher or
2 4.5 KG CO2 extinguishers shall be provided for every
300m2 of floor area for ordinary and high hazard risks (and for
every 450m2 in case of light hazard risks)
The appliances shall be so distributed over the entire floor
area, that a person has to travel not more than 15 m to reach
the nearest appliance.
Generally, hand appliances shall be placed as near as
possible to exits or staircase landings.
Installation of Hand Appliances as per the Committee’s
Regulations is a prerequisite for any occupancy, other than
storage occupancy
• Dry chemical powder fire extinguishers 25/50/75 kg
capacity: IS:10658/ UL299(in addition to 10kg DCP
requirement)
• At least one fire extinguisher should be provided for every
750 m2 of hazardous operating area.
• CO2 extinguishers 4.5/6.5/9.0/22.5 kg capacity
(IS:2878/UL154)At least one fire extinguisher should be
provided for every 750 m2 of hazardous operating area.
• To be located in substations, power stations, office
building and control room. The number should be
determined based on the maximum traveling distance of
15 metre.
• At least one fire extinguisher shall be provided for every
250 m2 of hazardous operating area. There shall not be
less than 2nos.extinguishers at one designated location
e.g. control room.
• Portable clean agent extinguishers
• This should be as an alternate to CO2 extinguisher.
• To be located in control rooms, computer rooms,
laboratories and office buildings.
• Dry chemical powder (DCP)* fire Extinguishers -10 kg
capacity: IS:15683/UL299
• Extinguisher to be located in process units, pump houses,
pump area, LPG storage area, LPG bottling plant, Oil
separator, tank truck/ tank wagon loading areas,
substations, Work shops, laboratory, power station
buildings etc.
• The number should be determined based on the max.
Traveling distance of 15 M in above areas. At least one
fire extinguisher shall be provided for every 250 m2 of
hazardous operating area. There shall be not less than
two extinguishers at one designated location e.g. pump
house.
In place of 10 kg, 5 Kg DCP Extinguisher shall be provided at
elevated locations.
Small Bore Hose Reels:
This sort of protection is not deemed suitable for
buildings/compartments containing electrical apparatus only or
in respect of buildings/ compartments in which flammable
liquids are stored and/or used
no part of the floor SHOULD BE more than 6 m. distant from a
hose nozzle when the hose is fully extended
• Rubber hose reel (25mm)
To be located in Process unit battery limits and other process
areas for quenching of incipient fires.
HYDRANTS/FIXED MONITORS:
The stand posts shall be 80 mm in diameter for single headed
hydrants. 100 mm for double-headed hydrants and monitors of
63 mm or 75 mm size and 150 mm for monitor of 100 mm
size.
N.B - Orifice plates of suitable design may be provided for
hydrants where the pressure exceeds 7 kg. /cm2
At least one hydrant post shall be provided for every 60 m of
external wall measurement in case of Light Hazard
Occupancy, for every 45 m in case of Ordinary Hazard
Occupancy and every 30 m of external wall measurement or
perimeter of unit battery limit in case of High Hazard
Fire hydrants around the tanks to be provided with 4” pumper
connection.
Hydrants / Monitors shall be located with branch connections and
not directly over main header
1

2. Occupancy.
NOTE: Notwithstanding the above, hydrants protecting utilities
and miscellaneous buildings in High hazard risks may be
spaced at 45 m.
No building shall be deemed to be protected by a hydrant
unless such hydrant is within 15 m of the building. Where any
part of a building is normally used for storage purpose or
where hazardous processes are carried out, there shall be two
single or one double headed hydrant within 15 m of the
building.
In case of Buildings/Plants occupied for High Hazard process
or storages, the above-specified distance may be increased to
22.5 m.
The hydrants/monitors shall be located at a minimum Distance of
15 M from the periphery of storage tank or hazardous equipment
being protected
this distance shall not be less than 5 M and more than 15 M from
the face of building.
Hydrants / Monitors shall be located along road side berms for
easy accesibility
All hydrant outlets shall be situated at a workable height of
about 1 metre above ground level.
All hydrant outlets shall be situated at a workable height of about
1.2 metre above ground level.
In case of storeyed buildings, satisfactory access shall be
provided to all parts of each floor by means of incombustible
internal or external staircases. Normally, a minimum of two
such staircases will be needed per compartment, but in case
the area of the compartment exceeds 2,000 sq. m., an
additional staircase shall be provided for every additional
1,500 sq. m. or part thereof.
On the other hand, if a compartment has a floor area of less
than 500 sq. m., one access staircase shall be acceptable.
Hydrants within buildings shall be in accordance with IS 3844.
Dry/Wet Risers with hydrants should be provided on each floor of
technological structures.
Tall columns, structure, towers and equipment will be
considered as protected by hydrants at ground level, provided
they are less than 15 m in height. When the height exceeds
15 m, the concerned hydrants shall be replaced by monitors.
Alternate hydrants for protection of loading unloading bays,
rail/truck gantries shall be replaced by water/foam monitors.
A minimum of 2 monitors shall be provided for the protection of
cluster of columns, heaters, gassifiers, etc., and where it is not
possible to approach the higher levels.
Field adjustable variable flow monitors shall be installed atcritical
locations
The location of monitors shall not exceed 45 M from the hazard to
be protected.
Tank Wagon & Tank Lorry loading/unloading gantry area shall be
provided with alternate water cum foam monitors having
multipurpose combination nozzles and fire hydrants located at a
spacing of 30 M on either sides of the gantry.
Storage of material in the open
Metals, Metallic goods, Machinery and other non-hazardous storage-
One single hydrant for every 60 m of storage periphery located beyond 2 m but within 15 m of storage area.
Coal or Coke-
One single hydrant for every 45 m of storage periphery located beyond 2 m but within 15 m of storage area
Hydrants shall be protected if subject to mechanical damage
combustible/flammable liquid storage
Hydrants shall be located beyond 15 m, but within 35 m of tank shell as specified below -
Tanks upto 10 m dia.One double headed or two single headed hydrants.
Tanks above 10 m but upto 20 m dia.Two double headed or four single headed hydrants.
Tanks above 20 m dia.Three double headed or six single headed hydrants.
Protection of spheres/bullets,
Upto 50 m3 WATER CAPACITY-Three single hydrants (or one single + Two double headed hydrants)
Above 50 m3 but upto 150 m3-One monitor + two single (or one double headed hydrants)
Above 150 m3-Two monitors + four single hydrants (or two double headed hydrants)
Pump rooms shall be located 6 m away from all surrounding
buildings and overhead structures.
N.B. for High Hazard (B) occupancies, the pump room shall be
located 30 m clear of all equipment where flammable fluids
having flash point below 65o C are handled and/or stored
OISD
Firewater pumps shall be located as far away as possible (not less
than 60 M) from hazardous areas
PUMPS:
Nos and Capacities of pumps are given in F p Manual in tabular form for different kinds of hazards
In calculating the number of hydrants in the system, a double headed hydrant shall be counted as two, a fixed monitor of 63 mm size
having nozzle bore of 32 mm shall be counted as three, a fixed monitor of 75 mm size having nozzle bore of 38 mm shall be counted
2

3. as four and a fixed monitor of 100 mm size having nozzle bore of 45 mm as six hydrant points
The diameter of the suction pipe shall be such that the rate of flow of water through it does not exceed 90 m. per minute when the
pump is delivering at its rated discharge. If, however, the pump is situated below the level of its water supply, the diameter of the
suction pipe/header shall be based upon a rate of flow not exceeding 120 m. per minute.
LIGHT HAZARD RISKS.
The pump delivery pressure will need to be 7 kg/cm2 if the highest floor of the risk is at a height exceeding 15 m above the
surrounding ground level.
Where the systems are hydraulically designed, The total pumping capacity need not be greater than 190 (683) irrespective of the
number of hydrant points.
ORDINARY HAZARD RISKS
Where the systems are hydraulically designed, the total pumping capacity need not be greater than 302 (1092) irrespective of the
number of hydrant points.Where the hydrant service consists of more than one pump, not more than half the total number (total
number + 1 in case of odd number) of pumps shall have prime movers of one type.
Where plants and other facilities are protected by sprinkler system tapped from the pressurised hydrant service
If the total water requirement for sprinkler system exceeds the requirement of the hydrant service as per Table 2, the pumping
capacity shall be equivalent to the former.
Where seawater is used or where the quality of water necessitates the use of special metals/alloys, the use of such metals or alloys
shall be insisted.
where the water demand for water spray and/or foam protection is in excess of that required for the hydrant system, the pumping
capacity shall be based on the higher water demand.
HIGH HAZARD RISKS
In case of High Hazard (B) risks where the aggregate pumping capacity required exceeds 1,640 m3/hr., larger capacity pumps are
acceptable provided the capacity of the largest pump does not exceed 25 % of the aggregate installed pumping capacity
where double headed hydrants are used throughout the risk a double headed hydrant may be regarded as a single hydrant only.
COMPRESSION IGNITION ENGINE DRIVEN PUMPS
Engines, shall have bare engine horsepower rating equivalent to the higher of the following two values
• 20 % in excess of the maximum brake horsepower required to drive the pump at its duty point.
• The brake horsepower required driving the pump at 150 % of its rated discharge.
FUEL TANK:
The tank shall be mounted above the engine fuel pump to give gravity feed. capacity of the tank shall be sufficient to allow the engine
to run on full load for –
Light Hazard-2 Hours
Ordinary Hazard- 4 Hours
High Hazard (A) -6 Hours
High Hazard (B) 8 Hours
PUMPS
Fire Pumps in High Hazard (B) category occupancies shall be
provided with positive suction and automatic starting devices
capable of sequential starting of the pumps.
The capacity and number of main fire water pumps shall be fixed
based on design fire water rate,
The capacity of each pump shall not be less than 400 m3/hr or
more than 1000 m3/hr.
When total number of Working pumps work out to be one or
two,100% standby pumps shall be provided.
ii) When total numbers of working pumps are more than two, 50%
standby pumps shall be provided.
Number of diesel driven pumps shall be minimum 50% of the total
number of pumps (inclusive of standby pumps).
2 Jockey pumps (1working plus 1 standby) shall beprovided.
maximum water requirement for spray application should generally
not exceed 1200 m3/hr.
• Pressurised Storage vessels-10.2 lpm/m2
• Volatile product service pumps located under pipe racks-
20.4 LPM/m2
• Columns/Other extremely hazareas-10.2 LPM/m2
• LPG Pump house-20.4 LPM/m2
• LPG Truck/Wagon Loading gantries-10.2 LPM/m2
• LPG Bottling Plants/ Cold repair shops-10.2 LPM/m2
• Oil Truck/Wagon Loading gantries-10.2 LPM/m2
• Cable trays-10.2 LPM/m2
Transformers-10.2 LPM/m2
3

4. Floating roof storage tanks and floating-cum-fixed storage
tanks exceeding 30m in diameter and fixed roof storage tanks
containing products having flash point below 32o C shall be
considered as hydrant protected only if, supplementary
medium velocity water spray system or fixed/semi fixed foam
system is also provided.
In case of foam system, there shall be additional protection by
water spray system in the form of a ring along the top edge of
the vertical face of the tank. Where tanks are protected by a
medium velocity water spray system tapped from the hydrant
service, the water requirements of the spray system shall be
calculated for tanks located in a common dyke which have the
largest aggregate shell surface area at a rate of 10 litres
/minute/m2 of tank shell surface area except where the system
has been designed to comply with the provisions contained in
N.B 4 under rule 7.6.19 (mandatory protection) in which case
the rate of flow can be reduced to 3 lpm/m2).
Even in the case of tanks located in separate dykes, the shell
surface area of all tanks located within a distance of 15 m (or
the diameter of the larger tank if the same is more than 15m)
shall be aggregated and the water demand of such cluster of
tanks shall be calculated at the rate of flow indicated in the
foregoing paragraph.
The water requirement of the spray system shall then be
loaded for supplementary hose stream protection as under –
Where the largest tank in, in a dyke, has a diameter –
Upto 10 m-1,150 LPM
More than 10 m and upto 20 m-2,250 LPM
Over 20 m,-4500 LPM
spheres/bullets
Taking into consideration the configuration of bullets/sphere,
the one which has the largest number of other bullets/spheres
within R +15 M of the centre thereof shall be selected.
The water demand shall then be worked out at the rate of 10
L/min/M2 of the aggregate shell surface area of the
bullet/spheres concerned and all bullets/spheres within R + 15
M of the centre thereof.
The water requirement of the spray system worked out shall
then be loaded for supplementary hose stream protection as
under -
Upto and including 50 m3-1,750 LPM
Above 50 m3 upto 150 m3-2,250 LPM
Above 150 m3-4,500 LPM
plants and other facilities
Where the plants and other facilities are protected by medium
velocity water spray systems, tapped from hydrant service,
water requirement of the spray system shall be loaded by
4,500 LPM for supplementary hose stream protection.
Transformers
Where transformers are protected by high velocity water spray
system tapped from hydrant system, water requirements of the
spray system shall be determined as per Committee's rules for
water spray system. Water requirement of the spray system
worked out as above shall then be loaded by 1,750 LPM for
supplementary hose stream protection.
All the tank farms and other areas of installation where
hydrocarbons are handled shall be fully covered by hydrant
System.
4.2.1 Fixed Water Spray on storage Tanks
• i) Class A Petroleum storage in above ground tanks shall
have fixed water spray system, whether floating roof or
fixed roof.
• ii) Class 'B' Petroleum storage tanks of following
dimensions shall be provided with fixed water spray.
• - Floating roof tanks of diameter larger than 30 M
• - Fixed roof tanks of diameter larger than 20 M.
Semi-fixed Foam system shall be provided for the following tanks:
• - Floating roof tanks storing Class 'A' and Class 'B'
petroleum products.
• - Fixed roof tanks storing Class 'A‘ and class 'B' petroleum
products.
• - Fixed roof tanks storing class 'C'petroleum products, of
diameter larger than 40 M.
•
Automatic actuated rim seal fire detection and extinguishing
system shall be provided on all existing aswell as new external
floating roof tanks storing Class A petroleum.
Only those Rim seal protectionsystems, which use the linear
heathollow metallic tube type detectorsshall be used.
Water application rate
• Atmospheric storage Tanks
• 3 Ipm/m2 of tank shell area for tank on fire
• 3 Ipm/m2 of tank shell area for exposure protection for
tanks located within (R+30) M from centre of tank-onfire
within the same dyke area.
• 1 Ipm/m2 of tank shell area for exposure protection for
tanks located outside (R+30) metre from centre of tank-
on-fire within the same dyke area.
LPG and hydrogen Pressure storage vessels shall be provided with
automatic water spraysystem.
ii) Automatic water spray system shall be provided in LPG bottling
stations, LPG loading/unloadinggantries and LPG pump
andcompressor
Oil loading/unloading Tank Truck &Tank Wagon Gantries shall be
provided with water spray and/or foam system.
In case automatic fixed water spray system is provided in TW
gantry, the gantry may be divided into suitable number of segments
(each segment having min. length of 15 m length & width of 12 m)
and three largest segments operating at a time shall be considered
as single risk for calculating the water requirement.
HVWS system for Transformers/Cable Galleries
a provision shall be made to actuate the water spray system from a
safe approachable central location
4

5. WATER SUPPLY
The effective capacity of the reservoir, shall be as indicated in
the table 1.
Reservoirs of and over 2,25,000 litres capacity shall be in two
interconnected equal compartments
Where the Fire pump(s) draw water from the reservoir under
suction lift conditions the two compartments shall be
connected to a common sump
In case of dual purpose reservoirs, the tapping for the general
water pumps shall be taken at a higher level such that the
capacity of the reservoir between tappings is at least
equivalent to the requirements indicated in Table 1.
The capacity of the reservoir for ordinary and high hazard
class occupancies may be reduced by the quantum of inflow
of one hour in case of ordinary hazard, 90 minutes in case of
high hazard (A) and two hours in case of high hazard (B)
occupancies), from a reliable sources, but in no case shall the
reservoir capacity be less than 70 % of that mentioned above.
Where rate of make up water supply is 50% or more, this storage
capacity can be reduced to 3 hours aggregate working capacity of
main pumps.
In case sea water or treated effluent water is used for firefighting
purposes, the material of the pipe selected shall be suitable for the
service.
Suitable provisions shall be kept for make up firewater from various
sources like ETP, Process from various sources like ETP,
ProcessCooling Water, river, ponds etc.
A terminal main of 80 mm diameter shall not feed more than one hydrant, that having a diameter of 100 mm shall not feed more
than two hydrants, that having a diameter of 125 mm shall not feed more than three hydrants and a main of 150 mm shall not feed
more than five hydrants.
In case where, owing to the size or layout of the building, or building being divided by internal walls, any point within the building is at
a distance of more than 45 m from an external fire hydrant, an internal hydrant system shall be provided so that no portion of the
floor is more than 45 m from an external hydrant or 30 m from an internal hydrant.
• N.B: Distance of 45 m indicated above shall be increased to 60 m for light hazard occupancies and reduced to 30 m for high
hazard occupancies.
Internal staircases shall be so located that atleast one of its enclosing walls is an external wall of the building.
Every opening from the staircase to any portion of the building or to a roof used as a floor shall be fitted with a single fireproof door.
N.B: The above rule will not apply to buildings, the upper floors of which are occupied by offices, air washer plants, rest rooms, cloak
rooms, canteen and the like.
For High Hazard occupancies, the hydrant system shall be
hydraulically so designed that when half the aggregate
pumping capacity is being discharged at the
farthest/hydraulically most remote point and the other half in
the most vulnerable area enroute, a minimum running
pressure of 5.25 kg/sq. cm is available at the former point and
the rate of flow of water does not exceed 5 m/second
anywhere in the system.
For Light and Ordinary Hazard Occupancies having more
than 55 points,
A single hydrant system may be installed provided, it is
hydraulically designed (where the highest hydrant is located
more than 20 m above ground level, pre calculated systems
shall not be accepted) as per the parameters indicated in N.B.
2 above, except that minimum running pressure shall be 3.5
kg/sq. cm. Instead of 5.25 kg/sq. cm
Fire water distribution ring main shall be sized for 120% of the
design water rate.
The fire water system shall be designed for a minimum residual
pressure of 7.0 kg/cm2g at the hydraulically remotest point of
application at the designed flow rate at that point.
Hydrant MAINS:
Wrought or mild steel pipes (galvanised or un-galvanised) of
‘Medium’ grade conforming to IS: 1239 or IS: 3589 having
welded joints and coated and wrapped as per IS: 10221
Holiday Testing for Wrapping and Coating is essential.
Un-plasticized PVC ‘Class 4’ pipes conforming to IS 4985 and
HDPE pipes conforming to IS: 4984.
N.B. These pipes are permitted for use in Light Hazard
Occupancies for underground mains only.
Pipes: Carbon Steel as per IS: 3589/ IS: 1239/IS:1978 or
Composite materials In case saline water/ treated effluent water is
used. pipes made of composite materials as per API 15LR/API 15
HR shall be used.
Provision of hose boxes should be given at critical locations for
housing hoses and nozzles.
As far as possible MS Steel pipes shall also be laid 1m below
ground level.
Mains above ground shall be adequately supported at regular
intervals on masonry or RCC stools or pedestals and not on
pipe racks.
Such Pipes shall be run at least 6 m away from the face of the
The main shall have at least 1.5 metre earth cushion under the
roads. In case of crane movement areas, pipes should be
protected with concrete/steel encasement.These shall not be laid
along with process piping on common sleepers.
piping should normally be laid above ground at a height of atleast
300 mm above finished ground level. However, the fire water
5

6. buildings and open storage areas in case of Light and
Ordinary Hazard Occupancies and 15 m. in case of High
Hazard Occupancies.
network piping shall be laid below ground level at the Road
crossings.
At least 10 % of all the welded joints shall be rediographically tested and half of the joints radiographed shall be the ‘field joints’.
The system shall be capable of withstanding for two hours a pressure equivalent to 150 % of the maximum working pressure. While
hydro-testing inclusion of cut-off valves in the mains to be tested should be avoided.
Mains shall be laid in rings and their sizes shall be as per Tables 3 & 3A.
Mains shall not be laid under buildings.
CUT OFF VALVES
Cut-off valves shall conform to IS: 780, PN 1.0
In case of system having working pressure in excess of 7
kg/cm2 PN- 1.6 rating would be necessary for valves
Cast Steel valves of class 150 are, however, acceptable
irrespective of the working pressure of the system.
Butterfly valves also can be accepted subject to the condition
that those exceeding 150 mm shall necessary be of gear
operated.
. Additional valves shall be provided in the segments where the
length of the segment exceeds 300 M.
Flushing connections with isolation valves should be provided at
suitable locations in the firewater ring main.
Fire Fighting staff
in no case shall be less than eight trained persons be available at any time during the day or night. Minimum number of trained
persons required may be further reduced to six in case of automatic pressurised hydrant systems.
REQUIREMENTS OF HOSE PIPES:
If hose is kept in central hose stations, for each of the first ten
hydrants in the compound of the premises two lengths of hose
15 m each and an additional 15 m length for each hydrant in
excess of ten, shall be provided.
In case of system having more than 55 hydrant outlets, the
total number of hose lengths required may be limited to 55
plus 20 percent of the number of hydrant outlets in excess of
55.
Where a fire engine is maintained on the premises the number
of hose, pipes required (including those on the engine) would
be 55 plus 10 percent of the number of outlets in excess of 55.
REQUIREMENTS OF NOZZLES:
The number of nozzles to be provided shall be equivalent to
half the number of hose pipes installed on the premises.
i) For installation with hydrants upto 100 Nos: - One 15 mtrs hose
length/hydrant.
ii) For installation with more than 100 hydrants: - One 15 metre
hose length/hydrant, for the first 100 hydrants; and, - One 15 M
hose length for every 10 hydrants above 100.
The hose length so calculated shall be suitably divided into hose
lengths of 15 M, 22.5 M or 30 M. Of the total Requirement of the
hoses, minimum 50% of hoses shall be of type B.
4" Hoses of suitable length for feeding to large capacity monitors
wherever installed.
Where storage tanks are protected by a fixed foam system
connected to the hydrant service, water requirement for the
foam system shall be equivalent to that required by the largest
protected tank at a rate of 5 litres/minute/m2 of liquid surface
area for fixed roof tanks and 12.2 lpm/m2 of rim seal in case of
floating roof tanks.
conditions regarding supplementary hose stream protection,
pumping capacity remain the same as for water spray
protection.
OISD
In determining total solution flow requirements, potential
foamlosses from wind and other factorsshall be considered.
For cone roof tanks containing liquid hydrocarbons, the foam
solution delivery rate shall beat least 5 Ipm/m2 of liquid surface
area of the tank to be protected.
For floating roof tanks containing liquid hydrocarbons foam solution
delivery rate shall be at least 12 Ipm/m2 of seal area with foam
dam height of 600 mm of the tank to be protected.
In case of floating roof sinking, the rate considered should be 8.1
Ipm/m2 of liquid surface areas.
FOAM COMPOUND:
The stock of foam compound to be maintained shall be
equivalent to at least two times the requirement of the tank
needing maximum quantity of foam. Foam Compound shall be
chemically neutral (PH 6.5 to 7.5)
OISD
• Foam compound: (IS: 4989 (Part-III)
• Higher of the quantities in :
• 1. 60,000 litre (excluding that in foam tender) for
installation having largest tank of diameter as 60 M.
• 2. 77,000 litre for installation having largest tank of
diameter as 79 M.
• Minimum of 90% of storage of foam compound shall be of
AFFF type. Minimum life of foam compound shall be
taken as per manufacturer's data.
• Foam compound should be tested periodically for
ensuring its quality and the deteriorated quantity replaced.
- Quantity of foam compound equal to 100% of requirement
should be stored in the Installation, subjected to a
minimum of 60,000 litres. However, for installations
having tankages larger than 60 M diameter, minimum of
6

7. 77000 liters foam should be stored
- 4000 kg for the DCP tender plus 500 kg for additional
requirement.
Electric supply for fire pumps
A direct feeder without any tappings shall be laid from the sub-
station to the pump house. The feeder shall consist of an
armoured cable buried underground and shall not pass under
any building or permanent structure.
The electric supply to the pumping set(s) shall be entirely
independent of all other equipment in the premises i.e. even
when the power throughout the entire premises is switched off,
the supply to the pump shall continue to be available un-
interrupted.
Transformer cubicles inside these sub-stations shall be
separated from H.T. and L.T. cubicles and from each other by
blank walls of bricks/stone/concrete blocks of 355 mm
thickness or of R.C.C of 200 mm with door openings, if any
therein, protected by single fireproof doors. The sub-station(s)
and D.G. house(s) shall also be separated from each other as
above.
Baffle walls of bricks/stone/concrete blocks of 355 mm
thickness or of R.C.C. of 200 mm thickness shall be
constructed between two transformers and these walls shall
be extended horizontally 600 mm beyond the extremities of
the transformers and vertically 600 mm above the highest
point of the transformers.
The fire pump circuit shall be protected at the origin by an
automatic circuit breaker Further, the under voltage
release/`no volt’ coil of the circuit breaker shall be removed.
The motor rating shall be equivalent to the horsepower
required to drive the pump at 150 % of its rated discharge
The sub-station(s) and/or D.G. house(s)-supplying power to
the fire pump(s) shall be located at least 6 m away from all
surrounding buildings.
Where this is not feasible, all door and window openings of the
surrounding buildings within 6 m of the sub-station(s) and/or
D.G. house(s) shall be protected by single fireproof doors and
6 mm thick wired glasses in steel framework respectively. The
above provisions shall also apply when the sub-station(s) and
D.G. house(s) are within 6 m of each other.
OISD
A direct feeder dedicated only to fire water pumps shall belaid from
the sub-station to ensure reliable power supply. The direct feeder
line shall not run along with other HT cables.
The system shall ensure auto start of the standby pump in case a
pump in sequence failed to take start.
Power supply to the electric driven pumps should be from two
separate feeders.
SPECIAL DISPENSATIONS FOR ELECTRICAL GENERATING STATIONS
WATER SUPPLY:
The fore bay supplying water to the thermal power station fed by canals from perennial water sources like rivers, rivulets, dams etc.
may be accepted as firewater reservoir
The cooling water pond (s) may also be accepted as firewater reservoir
NOTE: Cooling water basins shall not be acceptable as equivalent to cooling water ponds.
PUMPS:
Higher capacity pumps not exceeding 410 m3/hr and 88 m head may be acceptable. In order to achieve the minimum pressure of
3.5 Kg./cm2 at higher elevation, booster pump(s) with a capacity of 137 m3/Hr., having requisite rated head may be acceptable.
Electrically driven booster pump(s) shall in addition to the normal supply be connected to the emergency power supply also.
ABOVE GROUND HYDRANT MAINS:
In case of practical difficulties in maintaining the stipulated distance from the face of the building in case of above ground over head
mains, warranted under demanding circumstances in specific areas, for example between Boiler House and TG Building and
between Transformer and T.G. Building, the same may be permitted provided the mains installed in such areas form part of sub-ring
only.
STAIRCASES FOR STOREYED TG HALL/BOILER HOUSE/MILL BAY:
At least 50 % of the number of staircases thus arrived at shall conform to Rules 7.6.15.1, 7.6.15.2 and 7.6.15.3.
REQUIREMENT OF HOSE PIPES IN T.G.HALL/BOILLER HOUSE/MILL BAY:
For use with each hydrant on staircase landing two lengths of hoses 15 m each and a nozzle with attached branch pipe shall be
provided in hose box alongside each landing valve.
TAC SPL RULINGS
Piers, Wharfs and Jetties - to be classified normally under ordinary hazard category unless Category III of list of hazardous materials
7

8. are handled.
In case of new systems where the number of hydrants is expected to be between 100 and 150; and where further extension of the
system beyond 150 hydrants is not anticipated, a single pump of 410 m3/hr capacity at 7/8.8 Kgs./cm2 may be permitted.
Likewise in case of old installations where the system is extended beyond 100 hydrants but not exceeding 150 hydrants; and where
further extension beyond 150 hydrants is not anticipated, an additional pump of 171 M3/hr. at 7 Kgs./Cm2 may be permitted.
Where spray system/sprinkler system is provided for the protection of equipment/plant the water demand of such a system should be
worked out and compared to the water demand of tanks of 10 M, 20 M and beyond 20 M dia. and he supplementary hose stream
protection indicated for the equivalent tank diameter shall be provided
Where hydrant/monitors located along one longer side of a storage area are more than 90 m from those along the other longer side,
monitors having jets of longer reach may be accepted
ADDITIONAL OISD RULES
PETROLEUM PRODUCTS
Class 'A' Petroleum: Liquids having flash point below 23 degrees C.
Class 'B' petroleum: Liquids havingflash point of 23 degrees C and above but below 65 degrees C.
Class 'C' petroleum : Liquids having flash point of 65 degrees C and above but below 93 degrees C.
Excluded Petroleum: Liquids having flash point of 93 degrees C and above.
b) Classification for heated products :
At locations where the handling temperatures are higher than the flash point of the product in circumstances where product handled
is artificially heated to above its flash point, class 'C' product shall be considered as Class 'B' product and Class 'B'product shall be
considered as Class 'A' product.
OISD
Fixed Remote / Manual operated High Volume Long Range Water cum Foam Monitors
They shall be provided in
• i) Tank farm area. (all the tanks in the installation shall be within the horizontal range of foam throw.)
• ii) Inaccessible areas such as column, reactor, compressor house etc in critical units like CCRU, DHDS, HCU, Hydrogen,
FCCU, DCU, CDU
• iii) Critical equipments at higher locations (above 45 mtrs.)
• The electrical or hydraulic remote control mechanism shall be in line with Hazardous Area Classification.
Number and capacity of monitor shall be provided in such a way that foam application rate from the monitors meet requirement of
foam application rate (8.1 LPM/m2) for full surface tank fire
Water Spray System in Process Unit shall be provided for hazardousareas like
Un-insulated vessels having capacity larger than 50 m3 and containing class A or B flammable liquid.
Vessels inaccessible to fire tender/ mobile equipment, fire hydrants
Pumps handling petroleum products class 'A' under pipe racks.
Pumps handling products above auto-ignition temperature underpipe racks
Air fin coolers in hydrocarbon service located above pipe racks /elevated location.
Water spray rings for columns of height more than 45 M shall be provided
Building/sheds storing combustible and flammable materials.- to be sprinkler protected
FIREWATER FLOW RATE
Several combinations of flow requirements shall be assumed for design of network.
Also whenever firewater demand increases due to addition of plant & facilities or extensive extension of network, fresh Hydraulic
analysis shall be carried out.
The fire water system in an installation shall be designed to meetthe fire water flow requirement forfighting two fires simultaneously
or single fire for largest floating roof tank roof sinking case, whichever requiring largest water demand.
Two of the largest flow rates calculated for different sections as shown below shall be added and that shall be taken as design flow
rate.
i) Fire Water flow rate for tank farm shall be aggregate of the following:
Water flow calculated for cooling atank-on-fire at a rate of 3 Ipm/m2of tank shell area.
Water flow calculated for all other tanks falling within a radius of (R+30m) from the center of the tank on fire at a rate of 3 Ipm/m2 of
tank shell area.
Water flow calculated for all other tanks falling outside a radius of (R+30) M from centre of the tank on fire and situated in the
samedyke area at a rate of 1 Ipm/m2 of tank shell area.
Water flow required for applying foam into a single largest coneroof or floating roof tank (after the roof has sunk) burning surface
area of oil, by way of fixed foam system, where provided or by useof water/foam monitors.
Fire water flow rate for supplementary stream, shall be based on using 4 single hydrantoutlets and 1 HVLR 1000GPM)
8

9. simultaneously. Capacity of each hydrant outlet as 36 m3/hr and of each monitor as 228 m3/hr shall be considered
ii) Fire water flow rate for LPG sphere storage area shall be aggregate of the following:
Water flow calculated for cooling LPG sphere on fire at a rate of 10.2 Ipm/ m2 of sphere surface area.
Water flow calculated for all other spheres falling within a radius of (R+30) metre from centre of the sphere on fire at the rate of
10.2Ipm/ m2 of surface area.
Water flow for supplementarystream shall be considered as 372 m3/hr as indicated under item (i).
iv) Water flow rate requirements for fire fighting in other major areas shall be calculated based on criteria in terms of lpm/ m2 given
elsewhere.
In cases where two sets of firewater storage and pumps are provided, the number of pumps at each location shall be according to
hydraulic analysis of piping network
The capacity of jockey pumps shall be 5% minimum and maximum 10% of the design fire waterrate. Its head shall be higher than
themain fire water pumps. Auto cut-in /cut-off facility should be provided for jockey pumps
OISD
FOLLOWING PORTABLE EQUIPMENTS SHALL BE MAINTAINED
• Portable water-cum-foam monitor.
• Minimum 2 no. for Petroleum refinery and 1 no. for Gas Processing Plant
• Water Mist cum Compressed air Foam Technology:
• Minimum of one trolley type should be provided as an alternate to existing DCP system at each critical locations such as hot
pumps handling fluids above auto ignition temperature, like column bottom pumps at CDU, VDU, Coker,FCCU & HCU units
and minimum one back pack at critical high temperature column & exchangers in these units.
• Filling capacity - 35 to 50 litres for trolley mounted & 9 litres for backpack system.
• The exact number of fire tenders shall be higher of the items (a) or (b):
• (a) The quantities firmed up in each case based on two simultaneous major fires taking into Consideration the size, location
of the plant and statutory requirements.
• (b) The quantities indicated below.
• i) 3 nos. of foam tenders out of which two are for fire fighting one for spill/ standby. The foam tender should have foam tank
capacity of 3000/3600 Iitre and the pump capacity of minimum 4000 Ipm at 8.5 kg/cm2.
• a Multipurpose fire fighting skid should be used in lieu of one foam tender/ DCP tender as described
• Minimum 2 nos. of foam tank trailers with field adjustable variable flow water cum foam monitors having foam tank capacity
of 500-1000 liters and monitors capacity of minimum 1000 GPM
• Minimum 2 nos. of Trolley mounted water cum foam monitors of capacity of minimum 2000 GPM with field adjustable
variable flow
• iii) 1 to 2 numbers of Foam Nurser with foam compound tank of 7000 – 16000 litre capacity with suitable pump for foam
transfer.
iv) 1 to 2 nos. of portable/ trailer fire pumps of capacity ranging from 1800 to 2250 Ipm at discharge pressure of 7 kg/cm2 g.
FOAM QUANTITY
REQUIREMENT AS PER OISD
• should be calculated as sum total indicated below under items (i), (ii) and (iii) for a minimum period of 65 minutes.
• Foam solution application at the rate of 5 Ipm/m2 for the liquid surface of the single largest cone roof tank or at the rate of
12 Ipm/m2 of rim seal area of the single largest floating roof tank whichever is higher.
• However, a foam solution application rate of 8.1 Ipm/m2 of the liquid surface of the largest floating roof tank for 65 minutes
shall be considered for a roof sinking case.
• ii) One portable foam monitor of 4500 Ipm foam solution capacity.
• iii) Two hose streams of foam each with a capacity of 1140 Ipm of foam solution.
LOW EXPANSION FOAM: Foam expansion ratio can be up to 50 to 1, but usually between 5:1 to 15:1 as produced by self
aspirating foam branch pipes.
• The low expansion foam contains more water and has better resistant to fire. It is suitable for hydrocarbon liquid fires and is
widely used in oil refinery, oil platforms, petrochemical and other chemical industries.
HIGH EXPANSION FOAM: Foam expansion ratio vary from 501:1 to 1500:1, usually between 750:1 to 1000:1 is typically produced
by foam generators with air fans. This foam is used for protection of hydrocarbon gases stored under cryogenic conditions and for
warehouse protection.
PROTEIN BASE FOAM:
• The concentrate forms a thick foam blanket and is suitable for hydrocarbon liquid fires, but not on water miscible liquids.
FLUORO PROTEIN FOAM:
• . The foam is very effective on deep pools of low flash point fuels which have had lengthy pre burn time but not on water
miscible liquids
AQUEOUS FILM FORMING FOAM (AFFF):
• This can be used with fresh water as well as with sea water.It produces very fluid foam, which flows freely on liquid surface.
The aqueous film produced suppresses the liquid vapour quickly.
MULTIPURPOSE AFFF:
9

10. • Multipurpose AFFF concentrate is synthetic, foaming liquid designed specially for fire protection of water soluble solvents .
This can be used either with fresh water of sea water.The foam is also suitable for deep pool fires because of superior
drainage rate and more resistive to hot fuels/radiant heat. The 3% induction rate is suitable for liquid hydrocarbon fires and
5% for water miscible solvents.
• The process of adding or injecting thefoam to water is called proportioning.The mixture of water and foamcompound (foam
solution) is then mixed with air in a foam maker for onward transmission to burning surface.
FOAM CONVEYING SYSTEMS
• The system consists of an adequate water supply, supply of foamconcentrate, suitable proportioning equipment, a proper
piping system, foam makers and discharge devices
• There are three types of systems:
• i) Fixed
• ii) Semifixed
• iii) Mobile
Fixed foam conveying systemcomprises of fixed piping for water supply at adequate pressure, foam concentrate tank, eductor,
suitable proportioning equipment for drawing foam concentrate and making foam solution, fixed piping system for onward conveying
to foam makers for making foam, vapour seal box, and foam pourer.
Semifixed Foam System
• Semi-fixed foam system gets supply of foam solution through the mobile foam tender. A fixed piping system connected to
foam makers cum vapour seal box in case of cone roof tanks and foam maker and foam pourers in the case of floating roof
tanks conveys foam to the surface of tank.
Mobile Foam System
• Mobile system includes foam producing unit mounted on wheels which can be self propelled or towed by a vehicle. These
units supply foam through monitors/foam towers to the burning surface.
• Sub-surface foam injection
• This comprises of high back pressure foam generator connected near the bottom of the tank.
• Under the Seal Foam application:
• Foam travels through a flexible pipe inside the tank upto the center of the tank roof and exits at the seal rim of the floating
roof where the fire is located .
Automatic Actuated Foam Flooding system:
All the components and ingredients including premix solution are contained within the system. Such systems usually have a premix
solution supply tank pressurised by air or inert gas. The automatic sensing of fire releases this pressure and places the system into
operation.
Floating roof protection
foam shall be poured at the foam dam to blanket the roof’s rim seal.
Foam makers/foam pourers shall be located not more than 24 M apart on the shell perimeter based on 600 mm foam dam
height. The height of foam dam shall be at least 51 mm above the top of metallic secondary seal.
iv) A minimum of two foam pourers shall be provided.
FIXED ROOF TANK PROTECTION USING FOAM
a vapour seal chamber is required before the foam discharge outlet. to prevent entrance of vapour into the foam conveying
piping system
Tanks should be provided with foam discharge outlets/ vapour seal chambers as indicated below:
• Tank Dia in M. Minimum number of foam outlet
• upto 20 2
• >20 upto 25 3
• >25 upto 30 4
• >30 upto 35 5
• >35 upto 40 6
• >40 upto 45 8
• >45 upto 50 10
• It is based on pourer capacity of 1000 Ipm at a pressure of 7 Kg/cm2 upstream of eductor.
FLOATING CUM FIXED ROOF TANK PROTECTION
Protection facilities shall be provided as required for fixed roof tank.
DURATION OF FOAM DISCHARGE
• Tanks containing liquid
hdrocarbons - Class 'C'
petroleum .... 30 minutes.
• ii) Tanks containing Class 'A' & 'B'
Petroleum or liquids heated
above their flash points --- 65 minutes
• iii) Where the system's primary purpose is
for spill fire protection. --- 30 minutes.
10

11. DYKE AREA/ SPILLS/ OIL SEPARATOR PROTECTION USING FOAM
Portable monitors/ Medium Expansion foam generator/ foam hose streams shall be considered for fighting fires in dyke area, spills
and oil separator.
Clean Agent system is required for Control rooms & Satellite Rack Room (SRR) and Computer/Server rooms
DETECTION SYSTEM AND
ALARM
A flammable gas detector is designed to give a warning of the presence of flammable gases or vapours in air, well before they reach
explosive concentrations. Normally, the detector provides visible and audible alarm signals, but frequently it performs a further
function by initiating control action such as increasing ventilation or shutting off the source of gas. A flammable gas detector can also
be used for tracing leaks and checking that vessels or tunnels are gas free before entering.
AREAS TO BE COVERED WITH
DETECTORS
• - Light hydrocarbon pumps in process units.
• - Process cooling tower top platform in the units having pressurised cooling water return.
• - Fuel gas knock out drum
• - Suction side of forced draft air blowers if located where hydrocarbon vapours can be present.
• - Light hydrocarbon pump stations if located below grade level.
• - LPG Horton spheres
• - LPG pump house
• - LPG bulk truck loading area
• - LPG bulk wagon loading area
• LPG bottling, storage, repair sheds.
• - Gas compressor
• - Air-intake point for control room,
Following areas shall be provided with Smoke/ Flame / Heat detectors with alarm and/or system to actuate relevant fire
suppression system:
• - LPG spheres
• - LPG filling sheds
• - LPG pumps/compressors
• - LPG loading/unloading, both in tank truck and tank wagon gantry
• Hydrocarbon detectors shall be installed near all potential leak source
• of class-A e.g. tank dykes, tank manifolds, pump house manifold etc.
• following areas should also be provided with suitable detectors:
• - Extremely hazardous area in process units
• - Computer room, Server room,
• Process control rooms, Record room
• - Unmanned electric substations /MCC rooms
• - Cable galleries
• - Chemical Storage.
The fire alarm systems includes manualcall points (break glass), automatic gas/smoke/heat detectors, release &inhibit switches for
fire suppressing clean agent and conventional or microprocessor based data gathering panels viz. central fire alarm panel,
mimicpanels & associated equipments.
Manual Call Points shall be provided atsuitable locations like access point, approach roads, walkways etc. to cover the critical areas.
These manual call points activate the audio-visual alarm in the Central fire alarm panel installed in fire station and in the repeater
panel installed in the respective area control room(s). The location of these points shall be conspicuously marked on the
annunciation panel for proper identification. These manual call points should also have suitably wired telephone handset to facilitate
communication with respective area control room and fire station.
11