Schedule XXVI

(See rule 84)

FLAMMABLE LIQUIFIED OR COMPRESED GASES AND HIGHLY FLAMMABLE LIQUIDS

1. Applications:- Provisions of this Schedule shall apply to all factories where flammable liquefied or

compressed gases or highly flammable liquids are manufactured, stored, handled or used.

2. Definitions:- For the purposes of this Schedule,-

a) “bulk storage” means bullet or Horton sphere or mounded vessel used for storage of flammable

liquefied or compressed gases or highly flammable liquids having storage capacity exceeding one

thousand litres equivalent water holding capacity;

b) “bullet” means a horizontal cylindrical pressure vessel with hemispherical or dished ends used for

storage of flammable liquefied or compressed gas;

c) “explosive mixture” means a mixture of combustion agent (oxidizing substance in gaseous, liquid

or solid state) and a fuel (oxidisable substance in gaseous, liquid or solid state) in such proportions

that could give rise to a very rapid and violent oxidation reaction, liberating more kinetic energy

than is dissipated through conduction and convection, ultimately causing explosion;

d) “fire proof” means a passive means of protecting a structure or equipment or vessel from exposure

to direct fire or flame impingement or prolonged exposure to high intensity radiant thermal flux,

by the application of a coating or cladding of certain heat-resistant substance or mixture of a

specified rating;

e) “fire safe” means a provision of dual seating to control leakage to within acceptable level, even after

damage, due to fire, as applied to valves;

f) “flammable compressed gas” means flammable compressed gas as defined in rule 2 of the Static

and Mobile Pressure Vessels (Unfired) Rules, 1981 issued under the Explosives Act, 1884 (Central

Act IV of 1884);

g) “flammable liquefied gas” means a flammable gas kept in liquefied state by the application of

pressure at normal ambient temperature, 13% (thirteen percentage) or less of which by volume

with air forms a flammable mixture or which has a flammable range with air of at least 12% (twelve

percentage) by volume regardless of the lower flammable limits;

h) “gas free” means a condition where the concentration of a flammable gas in an equipment or a

vessel is well below the threshold limits (lower explosive limit), and it is safe for a man to enter into

the equipment or Vessel or to conduct “hot work” there, as the case may be;

i) “highly flammable liquid” means any liquid including its solution, emulsion or suspension which

when tested in a manner specified by sections 14 and 15 of the Petroleum Act, 1934 (Central Act

XXX of 1934) gives off flammable vapours at a temperature less than 32 degrees Centigrade;

j) “horton sphere” means a spherical Pressure Vessel, supported vertically and is used for the storage

of flammable liquefied or compressed gas;

k) “hot work” means an activity which may produce enough heat or spark to ignite a flammable

or explosive or explosive mixture;

l) “mounded vessel” means a pressure vessel for the storage of flammable liquefied or compressed

gas, which is placed above ground level and is completely covered by a mound of on earth or

similar inert material uncovering nozzles, manhole covers and inspection covers fitted on top of

the vessel;

m) “purging” means an act of replacing the atmosphere inside a vessel or a container with an inert gas

to such an extent as to push away the traces of flammable gases as to prevent the formation of an

explosive mixture;

n) “purging into service” means the process of replacement of gas in a closed system with an inert gas

and then replacing the inert gas with the desired flammable gas, vapour or liquid;

o) “purging out of service” means the replacement of flammable content within a closed system with

an inert gas and then replacing it with air to such an extent that it is gas free and safe for the entry

of any person for work;

p) “remote operated emergency valve” means a shut-off valve capable of being remotely

q) operated that closes automatically on loosing actuating power or in fire engulfment and which is

fire-safe.

3. Storage:- Every highly flammable liquid, flammable liquefied or compressed gas used in every factory

shall be stored in bulk in suitable tank made of adequate fire-resistant construction and located in a safe

position underground or in the open.

4. Location and spacing:- Before deciding on the location of any storage vessel, risk analysis study shall

be carried out and based on the risk analysis study, the storage vessel shall be located in the manner

specified below:-

a) The location shall not interfere with the movement of vehicles. The perceived Risk contour should

not intercept the public places such as assembly points, canteen, rest sheds and similar other

locations;

b) Before locating any storage vessel, the soil condition shall be assessed as desired by the

superstructure;

c) The storage vessel shall be placed above ground in open and in a well-ventilated place;

d) Mounded vessels shall be so located that the manholes and pressure relief valves are in a well-

ventilated position;

e) The minimum setback for safety between the storage vessels and buildings, boundary or fixed

ignition source shall be in accordance with the Static and Mobile Pressure Vessels (Unfired) Rules,

1981, as amended from time to time;

f) The storage vessels shall not be installed one above the other;

g) The bullets shall be so located that their dished ends do not point towards other vessels, vital

process equipments, control rooms, loading stations, nearby buildings or storage tanks containing

hazardous materials;

h) Raw vegetation such as weeds, short/long grass, deciduous shrubs and trees and any combustible

materials shall be removed from time to time from the storage vessel-area, covered under the

licenced premises;

i) The storage vessels shall not be located within the bunded enclosure of any heat source or other

flammable liquids, gases oroxidizers;

j) The storage vessels, pumping equipment, loading and unloading facilities and vaporisers

k) shall be located within at least 2 metres high fencing along the perimeter of the safety zone and the

fenced compound shall have at least two separate gates for the safe exit of persons and vehicles in

case of any emergency, preferably on the upwind/crosswind side.

l) The number of storage vessels in one battery shall not exceed six;

m) Storage vessels within a group shall be so located that their longitudinal axes are Parallel to each

other;

n) Spheres and bullets shall not be grouped together and shall be provided with separate piping

manifold, so as to avoid overfilling of a vessel due to head difference with another connected vessel

in the same manifold.

o) The top surface of the storage vessels installed in a battery shall be on the same plane so that the

pressure safety valve blow-out from them do not affect the other;

p) The flooring of the bullets or spheres, shall be sloped in such a way that the spilled liquid or high-

density gas from any vessel will not flow towards other vessels nearby;

q) The storage vessels shall be located in such a way that are high tension electrical cables will not

cross overhead or pass nearby the licenced premises in which they are kept;

r) Storage vessels shall not be kept in places that are susceptible to frequent flooding;

s) the level of the storage vessels shall be elevated slightly from the surrounding terrain to ensure

complete drainage of water;

t) every container, vessel or tank used for storing highly flammable liquid or flammable liquefied

or compressed gas shall be clearly and in bold marked “ Danger-Highly Flammable Liquid” or “

Danger-Flammable Liquefied or Compressed Gas”, as the case may be.

5. Design of storage vessels:-

a) General – Each static vessel for the storage of flammable liquefied or compressed gas shall be

provided with the following fittings and instruments which are suitable for use at pressures not

less than the design pressure of the vessel and for the temperatures appropriate to the worst

operating conditions, namely:-

(i) At least two pressure safety valves connected independently to the vapour space;

(ii) Two independent liquid level indicators;

(iii) A high-level alarm;

(iv) Two independent visible pressure gauges, connected to the vapour space; on both sides and

(v) Two temperature gauges for measuring the temperature of the contents of the vessel, on both

sides.

b) Vessel connections: - In every flammable liquefied or compressed gas storage vessel,

(i) all the connections to the vessel shall be designed and fitted in accordance with the Design

Code of IS-2825 or equivalent duly approved by the Chief Controller of Explosives;

(ii) more than one nozzle shall not be provided for inlet and outlet purpose, apart from the

drainage pipe;

(iii) the nozzle shall be a full – welded pipe extending up to a minimum distance of 3 metres from

the normal shadow of the vessel. A combination of manual and remote-operated-shut-down-

valve shall be provided on such nozzle shall have a slope of 1.5 degrees to the horizontal;

(iv) the nozzle shall be stress-relieved along with the vessels;

(v) there shall not be any flange, instrument tapping or manhole on this nozzle on the upstream

side before manual shut down valve and the remote operated valve; and

(vi) an excess flow valve shall be provided for the nozzle on the body of the vessel.

c) Pressure Safety Valve:- In every storage vessel,-

(i) the pressure safety valves provided shall be of spring-loaded type (weight-loaded safety valves

shall not be used). Each of the pressure safety valves shall have 100% relieving capacity;

(ii) the pressure safety valves shall be set to discharge at a pressure not more than 110% of the

design pressure of the vessel and shall have a total relieving capacity adequate for limiting the

pressure build-up in the vessel beyond 120%

(iii) of the design pressure;

(iv) the discharge of the pressure safety valves shall be connected to a flare system, if so available.

In cases of where the flare system is not available, the discharge from the pressure safety valve

shall be vented vertically upwards to atmosphere at a minimum elevation of 5 metres above

the top of the vessel for effective dispersion of the discharge. A loose-fitting rain cap with a

non-sparking chain extending up to the ground level and attached to the vent pipe shall be

provided on top of the pressure safety valve;

(v) an isolation valve shall be provided in between each pressure safety valve and the vessel. The

arrangement of the isolation valve shall be so designed to allow full required capacity flow

through at least one of the pressure safety valves; and

(vi) each pressure safety valve shall be visibly marked with the “set pressure” in kg/cm2 (gauge) at

which it will discharge, with its actual rate of discharge in cubic metre per minute at a pressure

of 120% of the design pressure of the vessel.

d) Emergency shut-off valve:- In every storage vessel,-

(i) all liquid and vapour connections, except those for pressure safety valves and the drainage

connections of diameter less than 25 millimetre shall have an emergency shut-off valve, such

as an excess flow check valve or a remotely operated valve:

Provided that the emergency shut-off valve is not required in cases where the connection to

a vessel is not greater than three centimetre in diameter for liquid and eight centimetre in

diameter for vapour;

(ii) Where the emergency shut-off valve provided is of ‘excess flow check valve’ type, its closing

rate of flow shall not be below the resulting rate of flow that is likely due to a fracture in the

line which it is protecting, in the worst condition so calculated. Excess flow check valve shall

have a flow capacity sufficiently above the normal flow requirements to prevent valve chatter.

e) Bottom water draw-off or drain valve:- In every storage vessel,-

(i) there shall be provided two drain valves at the bottom of the vessel between the remotely

operated valve and the first isolation valve. The length of the pipeline between the two drain

valves shall be at least 0.5 metre to minimize the risk of simultaneous obstruction of both

valves due to freezing of any water present in the liquefied gas. The drain connections shall

not be not more than 50 millimetre in diameter; The drain device shall not be insulated;

(ii) the first drain valve from the vessel shall be of gate type (throttle type), while the second drain

valve shall be of quick shut-off type; and

(iii) the material of construction for the drain pipeline and the related connections shall be suitable

of cryogenic material.

f) Sampling Valve: - Every storage vessel shall have, two valves fitted at 0.5 metre apart in the length

between the remotely operated valve and the first isolation valve, to provide for, sampling purpose.

(The provision of separation is for the purpose of avoiding freeze-chocking in the valve on the

upstream.)

g) Liquid level gauging device:- In every storage vessel, out of two-level indicators provided, one

shall be of “float” type and the other shall be of “differential pressure” type especially for Horton

Spheres. Magnetic float type gauge shall be used for bullets in place of “ differential pressure”

type. “High Level” alarm shall be set on the level indicators to operate at not more than 85% of

the volumetric capacity of the vessel. An audio-visual indication with high level alarm shall be

provided at or near the normal sitting place of the operator in a position visible all through the day.

h) Pressure gauge:- In every storage vessel, there shall be provided at least one pressure gauge, duly

calibrated, and having a dial range covering not less than 1.5 times the design pressure, that is easily

visible and consistently showing the correct internal pressure at all times. It shall be provided in

the vapour space at the top. A suitable stop valve shall be provided in between the vessel and the

pressure gauge for the maintenance and repair.

i) Gas sensors:- Every storage vessel meant for flammable liquefied or compressed gas storage shall

be provided with gas-sensors with alarm at vulnerable areas, which, in the event of gas leakage,

shall trip the compressor or pump, if in operation.

j) Bonding: - Electrical continuity shall be maintained between the flanges by bonding every storage

vessel and its pipe lines.

k) Pop off valves:- “Pop off” valves shall be provided in between isolation valves on the pipelines

carrying flammable liquefied or compressed gases.

l) Capacity of vaporizer:- The vaporizer connected to the flammable liquefied gas storage vessels shall

have adequate capacity to meet the required flow rate of flammable liquefied gas in the process.

6. Prevention of ignition:- In every location where highly flammable liquid or flammable liquefied or

compressed gas is stored, conveyed, handled or used or where there is danger of fire or explosion from

accumulation of highly flammable liquid or liquefied compressed gas in air, all practicable measures

shall be taken to exclude the sources of ignition. Such precautions shall include following:-

a) All electrical apparatus shall either be isolated from the area of risk or they shall be of such

construction installation and maintenance as to prevent any danger from there being a source of

ignition;

b) Effective measures shall be adopted to prevent static charges accumulation beyond a dangerous

limit;

c) No person shall wear or be allowed to wear any footwear having iron or steel nails or any other

exposed ferrous materials which is likely to cause sparks by friction;

d) Smoking, lighting or carrying of matches, lighters or smoking materials shall be prohibited.

e) Transmission bolts with iron fasteners shall not be used; and

f) All other precautions, as are reasonably practicable, shall be taken to prevent initiation of ignition

from all other possible sources such as open flames, frictional sparks, overheated surfaces of

machinery or plant, chemical or physical-chemical reaction and radiant heat or any other hot spot

whatsoever.

7. Earthing and bonding:-

a) All electrical systems and equipment’s and all structures, plants and other non-current-carrying

metallic parts of major electric apparatus or any major metallic object in any place where flammable

liquefied or compressed gases or highly flammable liquids are manufactured, stored, handled or

used shall be efficiently earthed; and the resistance valve of the earthing system relative to the

general mass of the earth, shall not be more than-

(i) 4 ohms in the case of electrical systems and equipment for a device that ensures the operation

of the protective device in the electrical circuit, whichever is lower and

(ii) 10 ohms in the case of all non-current carrying metallic parts of major electric apparatus or

any major metallic object.

b) All joints in pipelines, valves, plants, storage tanks and associated facilities and equipment’s for

handling flammable liquefied or compressed gases or highly flammable liquids shall be made

electrically continuous by bonding or otherwise; the resistance valve between each joint shall not

exceed 1 ohm.

c) A piping which is not in electrical contact with the associated tank or vessel shall be efficiently

connected to such tank or vessel by a flexible conductor and looped with earthing system.

8. Enclosed system for conveying highly flammable liquids:- Wherever it is reasonably practicable, highly

flammable liquids shall be conveyed within the factory, in totally enclosed system, consisting of pipe

lines, pumps and similar appliances from the storage tank or vessel to the point of use. Such enclosed

system shall be so designed, installed, operated and maintained as to avoid leakage or the risk of spilling.

9. Prohibition of smoking:- No person shall smoke in any place where a highly flammable liquid or

flammable liquefied or compressed gas is present and in similar circumstances where smoking would

give rise to a risk of fire. The occupier shall take all practicable measures to ensure compliance with this

requirement and he/she shall display a notice in a conspicuous place indicating prohibition of smoking

at all places where the requirement so applies.

10. Fire protection:- In every factory,-

a) No vehicular traffic shall be permitted within the risk area of lower flammable limit of the Highly

flammable liquid or flammable liquefied or compressed gas are stored. When required, only

vehicles fitted with approved spark arrestors may be allowed with valid vehicle entry permit.

b) All the vessels used for bulk storage or handling of highly flammable liquid or flammable liquefied

or compressed gases shall be protected against the hazards of fire as follows:-

(i) medium velocity water spray system shall be provided for all above ground level storage

vessels, cylinder storage or filling or repair sheds, pump houses, bulk lorry and tank wagon

gantries;

(ii) For fire detection, automatically actuated medium velocity water sprinkler system shall be

provided at all critical locations, such as bulk storage, tank/truck or tank wagon gantry, pump

or compressor house and vaporizers;

(iii) medium velocity water sprinkler system shall be based on heat or other detection signatures;

(iv) Quartzoid bulb protection designed to blow at a maximum of 79°C shall be provided in open

areas or in the sheds;

(v) medium velocity water sprinkler system shall function in such a way that the actuation of fire

detectors initiates the following and:-

(a) Opening of deluge valve;

(b) Blowing of audio-visual alarm at the fire pump house or control panel;

(c) Blowing of fire siren; and

(d) The diesel pump should get started based on the “Set pressure” to supplement or to

maintain the fire water pressure in the ring main; and

(vi) The medium velocity water sprinkler system shall have a minimum spray density of ten litres

per minute, per square metre in the case of flammable liquefied or compressed gas and in the

case of highly flammable liquid, a minimum spray density of 3 litres per minute per square

metre for the single largest risk area. For the purpose of calculation of a single risk area, the

following shall be taken into account:-

(a) In case of bulk storage, adjoining vessels within the distance of R+ 30 metre, where R is

the radius of the vessel and 30 metre shall be measured from the periphery of the vessel;

(b) In case of tank lorry gantry, a maximum of 8 bays shall be taken as a single risk area; and

(c) In case of tank wagon gantry, a minimum of one gantry [600 Metric Tonnes] shall be

taken as a single risk area.

c) (i) A fire water ring main shall be provided all around the locations of storage and handling

areas of flammable liquefied or compressed gases with hydrants or monitors spaced at

30 metres apart. Fire hydrants and monitors may be installed outside the licenced premises;

(ii) the fire water pressure system shall be designed to get a minimum residual pressure of

7 kg/cm2 (gauge) at the remotest place of application of the plant;

(iii) fire hydrant network shall be provided in closed loops to ensure multi-directional flow in the

system. Isolation valves shall be provided to enable isolation of any section of the network

without affecting the flow in the rest; and

(iv) the fire water system in the plant shall be designed to meet the highest fire-water flow

requirement for the medium velocity water sprinkler to cover a single largest risk area at a

time and shall ensure 288 metre 3/hour of water, for operating at least two fire water monitors

with supplementary hose requirements in addition.

d) (i) Water for the hydrant service shall be stored in any easily accessible, surface or underground

concrete reservoir or overhead tank of steel or concrete construction;

(ii) The effective fire water storage capacity available for fire-fighting shall last for at least four

hours; and

(iii) Storage tank or reservoir for water shall have two inter connected compartments to facilitate

cleaning and repair;

e) Portable fire extinguishers as approved by Bureau of Indian Standards shall be located at

convenient places as indicated in the Table below:-

TABLE

Area Portable Fire Extinguisher

(1) (2)

a) Flammable liquefied gas or storage vessels (each) two Numbers of 10 kg. DCP (Dry Chemical

Powder) each

b) Tank wagon loading or unloading gantries One 10 kg. Dry Chemical Powder extinguisher for every

15/20 metres of gantry

c) Tank truck loading or unloading gantries One 10 kg. Dry Chemical Powder Fire Extinguisher in

each Bay and 1 Number 50 kg. Mobile DCP Unit/gantry.

The dry chemical powder used in the extinguishers shall be Potassium or Urea based or Sodium

Bicarbonate as per IS: 4308.

11. Loading and unloading facilities for flammable liquefied or compressed gas:-

a) Loading:- In every factory, where the loading of flammable liquefied of compressed gas is carried

on, the loading station shall consist of the following:-

(i) A filling line with an isolation valve and check valve;

(ii) A vapour return line with a check valve and an isolation valve to return the vapour back to the

storage vessel from which the loading pump is drawing flammable liquefied gas;

(iii) Suitable loading arm or flexible hoses shall be provided at the end of filling line and vapour

return line for connecting to the tank-truck-vessels or tank-wagons; and

(iv) Suitable thermal pressure relief valve(s) shall be provided between the Shut-off valves to

protect against excessive pressure build up arising out of the thermal expansion of the trapped

liquid;

b) Unloading:- In every factory, where unloading of flammable liquefied or compressed gas is carried

on, and wherein a compressor is used for unloading the flammable liquefied gases by utilizing the

differential pressure between the receiving and discharging vessels, so created by withdrawing

vapour from the receiving vessel and forcing it at high pressure into the discharging vessel, the

factory shall have the following facilities:-

(i) Liquid unloading line; having isolation valve; and check valve in line; and

(ii) Vapour line with isolation valves.

c) Loading and unloading operations:- In every factory, where the loading or unloading of flammable

liquefied or compressed gas is carried on shall have:

(i) Written, operating procedures for loading or unloading operation, clearly defining the safety

checks and precautions to be observed as well as the responsibilities of the personnel involved

in such operation, prepared in English and in the language spoken by majority of workers and

given to those concerned and displayed at a prominent place;

(a) Flexible hoses used for transfer of flammable liquefied or compressed gas to or from a

tank truck or tank wagon shall be,-

(b) Designed and constructed in accordance with the Static and Mobile Pressure Vessels

(Unfired) Rules, 1981;

(c) A means of identification; and

(d) periodically checked for electrical and mechanical continuity and recorded in the register;

(ii) Provision for connecting and disconnecting hoses (only non-sparking type of tools shall be

used);

(iii) The tank-truck shall have a starter motor of non-sparking or flameproof type;

(iv) The tank-truck shall be parked on a levelled ground and vehicle arresting shall be placed at

front and rear wheels to arrest the vehicle movement;

(v) The engine of the vehicle shall be stopped and all the electrical equipment isolated, before

starting the loading or unloading or unloading operation; Before starting the loading or

unloading operation, static charges shall be effectively discharged by bonding and earthing of

the storage vessels with the road tankers or wagons and the ground;

(vi) The road tanker or wagon shall be electrically bonded at marked specified points with the

fixed grounding system;

(vii) Authorised person shall supervise the transfer operation and respond immediately in the

event of an emergency;

(viii) During loading operation, the pressure within the receiving tank-truck vessel shall be

observed to ensure that it falls within the start-off or triggering discharge-pressure of the

relief valve. Filling rate shall be regulated accordingly;

(ix) The receiving vessel which is having an internal pressure of less than 1kg/cm2 shall not be

taken in for filling. Such vessel shall be checked for Oxygen content or explosive mixture

content and purged, if necessary;

(x) Filling or transfer operation shall be done only during day time where visibility is adequate;

(xi) Filling or transfer operation shall be stopped immediately in the event of

(a) Uncontrolled leakage occurring;

(b) A fire occurring in the vicinity;

(c) Lightning and thunder-storm;

(xii) The “Safe Operating Procedure” for unloading shall be displayed in English, Malayalam

and Hindi and in the language understood by majority of workers in the unloading area.

12. Maintenance and Inspection:- In every factory where highly flammable liquid or flammable liquefied

or compressed gas is stored in bulk.-

a) The storage vessels and the safety fittings and instruments shall be tested periodically as per the

requirements under relevant statutes as applicable and records with such particulars of testing

maintained;

b) Loading or unloading hoses shall be tested at least once in every six months;

c) The earth pits shall be maintained well and the earth resistance measured at least once in every 12

months; and records kept in this regard;

d) The foundation and support of the storage vessels shall be checked once in a year for differential

settlement due to any unsettling at sub-soil level or of any other cause;

e) The cathodic protection, if provided, shall be monitored periodically and maintained well for

effectiveness;

f) The gas detection system shall be checked and calibrated periodically; and

g) The fire water system which includes fire water pumps, fire hydrant or monitor, piping network

and water sprinkler or deluge system shall be checked periodically and maintained well for its fail-

safe operation in adversaries.

13. Training: - The occupier of every factory in which highly flammable liquid or flammable liquefied or

compressed gases are stored in bulk shall ensure that-

a) The supervisory or managerial personnel are adequately trained in all aspects of safe storage and

handling of highly flammable liquid or flammable liquefied or compressed gas and in the disaster

control, preparedness and response.

b) Regular training programmes are conducted on loading or unloading operation, draining

procedure, commissioning and decommissioning procedures, “hot work” permit system,

fire-fighting and emergency combat operation, health hazards, safe working procedures, safe

behaviours at work place etc., for-

(i) Regular workers;

(ii) Workers including daily, part-time, badly, casual or any contractual fringe of that kind, etc.,

and

(iii) Security staff;

c) Full-scale emergency mock drills, simulating leakage of flammable gas and the consequences, are

conducted in the plant at least once in every six months and the level of preparedness, and the

adequacy of combat measures, assessed and modified from time to time, and any deviations, or

defects observed during such mock-drills rectified forth-with.

14. Exemption:- If in respect of any factory, the Chief Inspector-cum-Facilitator is satisfied that owing to

the exceptional circumstances or intermittent nature of the processes or for any other reason, all or any

of the provisions of this Schedule is not necessary for protection of the workers in the factory, the Chief

Inspector-cum-Facilitator may, by a certificate in writing, which he/she may at his discretion, revoke at

any time, exempt such factory from all or any of such provisions subject to such conditions, if any, as

he/she may specify therein.