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FIRE FIGHTING
Introduction
• Fighting fire is not a tasking for RCM-SAR.
• However knowledge of how to deal with a fire is important, should there be a fire on the rescue vessel, or the rescue vessel is called upon to rescue survivors from a vessel on fire.
Fire
Fire Tetrahedron
• Most fires need at least four components to survive. These are :
1. Heat
2. Fuel
3. Oxygen
4. Chain reaction• Fire extinguishing is based on removing or
interfering with at least one of these items
Fire Tetrahedron
For example:
Remove the air by using a fire blanket or by putting a layer of foam.
Remove the heat by using water to reduce the temperature.
Remove the fuel, by turning off the fuel valve, or pulling combustibles away so there is nothing less to burn
Fire Tetrahedron
• There is a fourth section which is where a extinguishing chemical such as halon can interfere with the chemistry of combustion, and this produces the “fire tetrahedron”.
Fire Tetrahedron
In Case of Smoke or Fire
• FIND - the fire, location and size• INFORM - inform everyone on board - make
distress call to other vessels • RESTRICT - stop air supply by closing doors,
hatches, windows, air ventilation, fuel cocks, turn off batteries, and turn vessel to blow smoke and flames over the side
• EXTINGUISH - use appropriate fire fighting system available.
Fire Extinguishers
Fire Extinguishers
Objectives
• IDENTIFY 3 common classes of fires
• SELECT the proper type of extinguisher
• EVALUATE when it is safe to
fight an “early-stage” fire, and;
• APPLY the “P.A.S.S. method to operate a portable extinguisher.
Untrained People cannot use a fire extinguisher safely because
they are:
• UNABLE to evaluate a fire
• UNAWARE of DANGER due to...
• LACKING JUDGEMENT regarding:
– Safe and correct use of, and
– Limitations of portable extinguishers
Why Untrained PeopleCan’t use a fire extinguisher safely
(continued):
INEXPERIENCED• Don’t know about the proper
type of extinguisher • Don’t know how to make a
“Fight or Flight” analysis• Unfamiliar with the “P.A.S.S.
method”
Fire Classifications
“Ordinary” combustibles Paper, wood, rubber, plastics
and textiles.
“Flammable liquids” Oil, gasoline, solvents
“Energized circuits”
Electrical equipment and computers
Fire Classifications
““Combustible Metals”Combustible Metals”
Certain combustible metals such as sodium, magnesium, potassium, etc. You should not generally meet this type of fire.
How They Work:
Works by Works by cooling.cooling. Numerical rating indicates amount of agent, duration, and
range of discharge on test fires.Area of Class A fire which a “non-expert” can extinguish, Area of Class A fire which a “non-expert” can extinguish,
with proper trainingwith proper training 1-A is 1-A is equivalent on Class-A fire to five liters of waterequivalent on Class-A fire to five liters of water. . 22-A contains has -A contains has twice as muchtwice as much extinguishing agent. extinguishing agent.
How They Work:
Works by blanketing the fuel. Works by blanketing the fuel. Interrupts chemical reaction at fuel surface.Interrupts chemical reaction at fuel surface.
Class B ratings signify the Class B ratings signify the area in square feetarea in square feet of of flammable liquid fire a unit will extinguish when used, by a flammable liquid fire a unit will extinguish when used, by a
trained, “non-expert.”trained, “non-expert.”
How They Work:
Class “C” units have no numerical rating.A Class “C” rating doesn’t imply any capacity.
Only indicates that the extinguishing agent is Only indicates that the extinguishing agent is non-non-conductiveconductive, safe on energized equipment., safe on energized equipment.
Works by displacing oxygen, smothering fire.
How They Work:
2A10BC
This is a comparison type of rating system and, in this case, it means that this extinguisher will put out 2 units of a class 'A' fire, 10 units of a class 'B' fire, and that it is rated for use on class 'C' fires. No value is assigned for class 'C', as it only implies that the extinguisher is safe and effective for use on live electrical fires.
Underwriter Laboratories of Canada
All Canadian extinguishers will have the above symbol
Portable Fire Extinguishers
LIMITED IN:
• Capacity - 1.5 to 25 lbs. of
extinguishing agent
• Range - Typically 3 to 15 feet
• Duration - Discharge their
contents in only 5 to 30
seconds!
Extinguisher Common Features
• Locking pin• Carrying handle / operating lever • Pressure gauge• Label :
– Type (Water, C02, Dry Chemical)– Classification (A, B, C)– Capacity Rating– Instructions
• Discharge nozzle or horn
Common Types Of Fire Extinguishers
• WATER • DRY CHEMICAL• CO2 and Halon
Water Extinguisher
• Water + CO2 propellant
• ONLY for Class firesONLY for Class fires
– wood / paper, etc.
• Spreads burning liquids!
• DANGERDANGER of electric shock if used on on live circuits!
Dry PowderMulti-Purpose Rated
• Best for general use:
• Reduced risk of re-ignition
• A 10 lb. unit empties in 8-10 secs.
– Effective range of 6 ft. to 15 ft.
Either Or
Carbon Dioxide - Rated
• Best on burning liquids / electrical
• SHORT range - 3 to 8 ft.
• 10- pound unit empties in 5 to 10 seconds!
– Use short spurts!
• DISPERSES QUICKLY!
– Continue applying after the fire is out!
• Unit gets VERY cold - hold properly
Halon Extinguisher
• Best for computers / electronics
• Weight-for-weight TWICE as effective as C02
• No residue, easy clean-up
• VERY SHORT range, 3 to 6 ft.
• Like C02, Discharges QUICKLY!
• Like C02, Disperses QUICKLY!
– Continue after flames are extinguished
P.A.S.S.
P.A.S.S.PULL
AIM
SQUEEZE
SWEEP
Remember 1) Keep your back to a clear escape route,2) Stand back 6 to 8 feet from the fire,3) Stay low below heat,4) Then >>:
PULL the pin
AIMLOW at the base of the fire
SQUEEZEthe lever
SWEEPfrom side to side
Servicing
• All extinguishers should be serviced annually
Approaching a Fire
Approaching a Fire
• Where the rescue vessel has been called to a burning vessel, conduct the Stop, Assess, Plan, looking for survivors, the source of the fire, and any items such as propane tanks, fuel tanks or diving tanks that are liable to explode.
Approaching a Fire
Approaching a Fire
• Always approach from windward of the casualty that is on fire, if circumstances permit, to stay out of the smoke.
• If survivors are still on board, urge them to don lifejackets, and jump off to windward to recover them from the water.
Water Wall•It is not work of RCM-SAR to extinguish vessel fires, but to recover survivors.
•RHIBs are not designed for fire-fighting.
•If an approach has to be made to a burning vessel to recover a survivor, one use of the de-watering pump is to generate a “water wall”.
•The hose nozzle will be adjusted to form a spray pattern, also called "water wall" and will protect the tubes and the personnel from radiant heat).
Water Wall
• WATCH the fire area– If the fire flares up, back out immediately and call
the fire department!
OK, It’s out…Now What?