1. Fire hazards and precautions on board
liquefied gas carriers
BY MT&C SASA FRKOVIC
2. IS LNG SAFE?
LNG consist of hydrocarbons which will burn when exposed to air and ignited by a suitable source of ignition.
LNG is a cryogen which means it must be distributed and stored in specialized equipment and tanks in order to keep in a
liquid state
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LNG vapors are flammable within a certain concentration range. This is called the “flammable range”; the limits
are commonly called the “Lower Flammable Limit” (LFL) and the “Upper Flammable Limit” (UFL). For natural gas
(methane) the range is 5-15%. This means that LNG will likely only ignite when the vapor concentration is between
5-15% in air .
Vapor concentrations outside this range contain either insufficient fuel or oxygen to ignite.
CAN LNG IGNITE ?
3. Sources of ignition
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There are many possible sources of ignition in the engine
room and gas carriers are designed to reduce the chances of
gas entering these spaces.
• DOORS- located away from the cargo area
•VENTILATION FAN INTAKES-positioned at high level
•ENTRANCES IN THE ENGINE ROOM –must be kept shut all
times
•All external doors and ports should be kept shut, especially
during loading and discharging operations.
present in spaces such as the accommodation, galleys and
engine rooms, and it is essential to prevent cargo vapour
entering these spaces.
4. Page 4
Procedure to follow in the event of a fire
•AT SEA FIRE
•VESSEL IN PORT
Scenario at sea
( Fire on the manifold port side )
•the initial alarm will be activated either
automatically by the fire detection system, or
manually by the person discovering the fire.
( most common continious alarm bell )
MANUAL RELEASE
ACTIVATION POINT
5. Page 5
•Action on deck : Fire parties muster and
report to Bridge, it is essential that the
Master is advised if any persons are
missing or unaccounted for.
•Master advises Ch Off/Ch Eng of result of
Muster & Fire Location if known
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Manoeuvre as required, traffic and
navigational situation permitting
Advise traffic in the vicinity on VHF Ch 16
and DSC VHF Ch 70
Consider use of following:
1. Fire/Water Spray Pumps
2. Vent Fan Stops
3. Engine to Standby
ACTION
ON THE
BRIDGE
7. Ch Off/Ch Eng takes control of Fire Fighting and Rescue operations
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Ch Off/Ch Eng takes control of Fire Fighting and Rescue operations
8. Page 8
• Ship’s staff to commence
fighting the fire using
normal drilled procedure
•Emergency party team
proceeding fight with fire
•Start water spray pump.
•Engine Room Party to
supply services in the
normal manner. (Fire Pump
would already be running
and Fire Main pressurised.)
•TARGET –Closing the
manifold valve which will
cutt off the source of fire
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METHOD OF TECHNIQUE TO BE USED:PROGRESSIVE
COOLING
•In its early stages, a fire may be effectively dealt with by
cooling the surface with advancing sweeps of fog or spray
across its whole width.
•It is highly effective because in the early stages the fire is
only fed from the vapours of a thin hot layer of LNG.