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TRANSCRIPT
21
Fire
Suppression
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Objectives (1 of 2)
• Describe offensive versus defensive
operations.
• Describe how to attack an interior • Describe how to attack an interior
structure fire.
• Describe how to operate hose lines.
• Describe exposure protection.
• Describe how to attack a vehicle fire.
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Objectives (2 of 2)
• Describe how to extinguish a flammable-liquid fire
• Describe how to extinguish a flammable-• Describe how to extinguish a flammable-gas cylinder fire.
• Describe a boiling liquid expanding vapor explosion (BLEVE).
• Describe how to attack fires involving electricity.
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Introduction
• Tactics and tasks to achieve
extinguishment of the fire
• Variety of methods• Variety of methods
– Remove fuel, oxygen, or heat
– Break chemical chain reaction
– Typically extinguish with water
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Offensive vs. Defensive
Operations• Interior operations are offensive.
• Exterior operations are defensive.
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Offensive Operations
• Exposes fire fighters to heat and smoke
• Apply extinguishing agent directly to
overpower the fire.overpower the fire.
• When successful, causes least amount of
property damage
• Used when fires are small
• Usually uses small handlines
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Defensive Operations
• Usually uses large handlines or master
streams
• Used when fire is too large for offensive • Used when fire is too large for offensive
attack or risk too great to fire fighters
• Objective is to prevent fire from spreading
• Water is directed from exterior while fire
fighters maintain a position of safety.
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Strategic Decisions
• Must be made by the incident commander
• Made prior to operations beginning
• Clearly communicated to personnel• Clearly communicated to personnel
• Confusion cannot exist
• The strategy may change during the
operation.
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Command Considerations
• What are the risks vs. potential benefits?
• Is it safe?
• Are there any structural concerns?• Are there any structural concerns?
• Are there any lives at risk?
• Does the size of the fire prohibit entry?
• Is there enough manpower?
• Is there an adequate water supply?
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Operating Hose Lines (1 of 2)
• Small handlines
– One fire fighter
– A second is helpful for
advancement and advancement and
maneuverability
• Large handlines
– Require two or more fire
fighters
– One can operate if well
anchored.
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Operating Hose Lines (2 of 2)
• Master streams
– Operated from a fixed position
– On the ground– On the ground
– On top of a fire apparatus
– On an elevating device
– Used for defensive operations
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Fire Streams
• Nozzle defines the pattern and the form of
the water discharged.
• Produced by either• Produced by either
– Smooth-bore nozzle
– Adjustable nozzle
• Operator must know how to set the
discharge pattern.
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Fog Stream
• Divides water into droplets with large
surface area
• Absorbs heat very efficiently• Absorbs heat very efficiently
• Can lower heat levels very quickly
• Usually adjustable from straight stream to
narrow fog to a very wide fog
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Straight Stream
• Provides more reach
• Keeps water concentrated concentrated
• Created by the narrowest setting on a fog nozzle
• Consists of highly concentrated droplets
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Solid Stream
• Produced by smooth-bore nozzles
• More reach and • More reach and penetration than straight stream
• Consists of a continuous column of water
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Points to Remember
• Air is moved along with the water.
• Fog streams move large amounts of air.
– Thermal balance may be disrupted, pushing – Thermal balance may be disrupted, pushing hot fire gases onto fire fighters.
• Straight streams move very little air,
causing less thermal inversion.
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Interior Fire Attack
• Offensive operation where fire fighters
enter a structure
• Fires inside a structure are much more • Fires inside a structure are much more
challenging and involve greater risk.
• Three methods of attack:
– Direct
– Indirect
– Combination
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Direct Attack
• Most effective method
• Uses straight or solid streamstream
• Delivers water directly to seat of fire
• Short, controlled bursts of water
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Indirect Attack
• Used when area is ready to flash over
• Short burst of water • Short burst of water applied to ceiling
• Uses straight, solid, or narrow fog stream
• Can cause serious injuries if too much water is used
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Combination Attack
• Employs both indirect and direct method
• Uses indirect to cool atmosphere, then
direct to extinguishdirect to extinguish
• Only use enough water to control the fire.
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Large Handlines
• Both offensive and defensive attacks
• Can extinguish larger • Can extinguish larger interior fires and have greater reach.
• More difficult to maneuver
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Master Stream Devices
• Produces high-volume water streams for
large fires
• Includes portable monitors, deck guns, • Includes portable monitors, deck guns,
ladder pipes, and other devices
• May be manually operated or by remote
• Should never be directed into a building
where fire fighters are inside.
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Deck Gun
• Permanently mounted with a piping system for the water
• The driver/operator can usually open a valve to start the flow.
• Sometimes may require a hose to be hooked up to operate
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Portable Monitor
• Positioned wherever needed
• Connected to supply • Connected to supply water
• May be equipped with a strap or chain
• Safety lock is provided to limit use beyond 35 degrees.
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Elevated Master Streams
• Mounted on aerial ladders, aerial platforms, or hydraulic boomsbooms
• Ladder pipe is mounted on an aerial ladder.
• Many have fixed piping for water
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Protecting Exposures–Fire Fighter
II Standard • Prevent fire spread
• Most important at large fireslarge fires
• Often, the best method is to apply water directly to exposed building exterior.
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Ventilation
• Before interior attack, structure must be
ventilated.
• Requires coordination• Requires coordination
• Allows hot smoke and gases out and
improves visibility
• Improperly done, may make it more
difficult for fire fighters
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Concealed Space Fires
• Fires may burn in void spaces.
• Must be found and • Must be found and extinguished to prevent from spreading
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Basement Fires
• Present many challenges to fire fighters
• Fire fighters should identify safe entry/exit points.
• Consider possibility of a basement fire when entering a structure.
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Above Ground-Level Fires
• Protect vertical paths
• Always look for secondary exit route.
• Risk of structural • Risk of structural instability and collapse
• Standpipes
• Stage equipment 1–2 floors below the fire.
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Fires in Large Buildings
• Fire fighters may become lost or
disoriented.
• Tag lines can be used to help prevent fire • Tag lines can be used to help prevent fire
fighters from becoming lost or from
running out of air.
• A preincident plan can be essential.
• Prior knowledge of occupancy and
hazards is helpful.
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Fires in Buildings During Construction,
Renovation, or Demolition
• These buildings are at greater risk.
• Often have large quantities of exposed
combustiblescombustibles
• Often have unlimited oxygen supply
• Fire systems may not be operational
• Subject to accidental and intentional fires
• If no life hazard, use defensive operations.
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Fires in Lumberyards
• Prime candidate for defensive operations
• Contains large quantities of combustibles
• Plenty of air is available.• Plenty of air is available.
• Exposure protection is primary objective.
• Collapse zones should be established.
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Fires in Stacked or Piled
Materials• Materials may collapse without warning.
• Approach very cautiously.
• Use equipment to move material.• Use equipment to move material.
• Class A foam often used to extinguish
smoldering fires
• Overhaul requires the materials to be
separated.
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Trash Container and Rubbish
Fires• Usually occur outside
of a structure
• Class A foam can be • Class A foam can be useful.
• Can use deck gun to extinguish fire then fill the container with water
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Confined Spaces
• Fires in underground vaults and
transformer vaults too dangerous to enter
• Contact the utility company.• Contact the utility company.
• OSHA requires special training and
permits.
• Space may be oxygen deficient or high in
combustible gases
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Vehicle Fires
• Common in most communities
• Important to wear SCBA
• Use 1½" or 1¾" hose line• Use 1½" or 1¾" hose line
• Gas-filled components may burst
• Consider other hazards.
• Do not risk fire fighter lives to save a
vehicle.
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Safe Area Around the Vehicle
• Only fire fighters within 50’
• Approach from uphill and upwind side.
• Sweep the bottom part of the vehicle.• Sweep the bottom part of the vehicle.
• Extinguish all visible fire while advancing
toward the vehicle.
• Foam can extinguish and prevent
reignition.
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Fires in the Passenger Area
• Use straight stream from 50' and approach
with slow, sweeping motion.
• Change to a fog when closer.• Change to a fog when closer.
• Foam can be used for any burning
flammable liquids.
• Begin overhaul after steam clears.
• Do not place yourself in path of airbags.
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Fires in the Engine
Compartment (1 of 3)
• Engine compartment filled with devices using petroleum productsproducts
• Batteries contain sulfuric acid.
• Direct water into wheel wells and through the front grill.
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Fires in the Engine
Compartment (2 of 3)
• Pull hood-release latch.
– If successful, trip secondary latch.
– If not, use a pry bar to pry up a corner on the – If not, use a pry bar to pry up a corner on the hood.
– Twist the hood-release cable with a gloved hand or a Halligan bar.
• Open the hood and extinguish fire.
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Fires in the Engine
Compartment (3 of 3)
• Overhaul same as a structure fire
• Use water liberally if significant damage
has already occurred.has already occurred.
• Disconnect the power by cutting the
battery cables.
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Fire in the Trunk
• Initial access by knocking out a tail light
• Use a Halligan tool to force the lock for
entry.entry.
• Charged line must be ready.
• Approach with caution.
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Alternative Fuel Vehicles (1 of 3)
• Be alert for these vehicles.
• Use unmanned master streams.
• Compressed natural gas (CNG).• Compressed natural gas (CNG).
– Cylinders similar to SCBA cylinders
– Usually in the trunk
– Nontoxic and lighter than air
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Alternative Fuel Vehicles (2 of 3)
• Liquefied propane gas (LPG)
– Cylinders similar to those in heating/cooking
– Heavier than air, vapors will pool or collect in – Heavier than air, vapors will pool or collect in low areas.
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Alternative Fuel Vehicles (3 of 3)
• Hybrid vehicles
– Small gasoline motors and large battery banksbanks
– Batteries are very hazardous and may explode when burning.
– Runoff is hazardous.
– High-voltage lines can cause serious injury or death if cut.
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Flammable Liquids Fires–Fire
Fighter II Standard • Found in almost any type of occupancy
• Most vehicles involve flammable or
combustible liquids.combustible liquids.
• Special tactics are required.
• Special extinguishing agents are needed.
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Two-Dimensional Fires–Fire
Fighter II Standard • Refers to a spill, pool, or container of liquid
where only the top surface is burning
• Controlled with appropriate Class B foam• Controlled with appropriate Class B foam
• Watch for hot surfaces or open flames
which may reignite.
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Three-Dimensional Fires–Fire
Fighter II Standard • Refers to a situation where burning liquid
is dripping, spraying, or flowing over the
edge of a containeredge of a container
• More difficult to extinguish with foam
• Dry chemical or gaseous extinguishing
agent is usually more effective.
• Do not stand in pools or contaminated
runoff.
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Propane Gas–Fire Fighter II
Standard • Used for heating, cooking, and vehicle fuel
• At temperatures above -44 °F exists as a
gasgas
• When stored under pressure, changes to a
liquid
• Expansion ratio of 270:1
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Propane Containers–Fire Fighter II
Standard (1 of 2)
• Space with propane gas above the liquid
level
• Piping draws from the vapor space.• Piping draws from the vapor space.
• Containers vary in size.
• Made of aluminum or steel
• Discharge valve controls the flow of gas.
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Propane Containers–Fire Fighter II
Standard (2 of 2)
• A connection hose, tube, or pipe allows
gas to flow to its destination.
• Cylinders equipped with relief valve• Cylinders equipped with relief valve
• Containers must be in upright position or
the relief valve may release liquid
propane.
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Propane Hazards–Fire Fighter II
Standard • Highly flammable
• Nontoxic but can cause asphyxiation
• Odorless• Odorless
• Heavier than air
• Approach uphill and upwind
• Full personal protective equipment
required
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BLEVE–Fire Fighter II Standard
• Boiling liquid expanding vapor explosion
(BLEVE)
• Pressure increases from heat.• Pressure increases from heat.
• Release valve may open to vent pressure.
• Container may fail violently.
• Best method of prevention is heavy
streams of water from a distance
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Flammable-Gas Fire
Suppression–Fire Fighter II
Standard (1 of 3)
• Shut off main discharge valve.
– Do not extinguish flames unless fuel source is shut – Do not extinguish flames unless fuel source is shut
off.
– Approach with two 1¾" lines set on a fog pattern.
– Team leader is between the lines.
– Once at the tank, reaches in and closes the valve
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Flammable-Gas Fire
Suppression–Fire Fighter II
Standard (2 of 3)
• Back away with lines still flowing.still flowing.
• For severe fires, use unmanned master streams and evacuate area.
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Flammable-Gas Fire
Suppression–Fire Fighter II
Standard (3 of 3)
• If relief valve is open, container is under
stress.stress.
• Will sound like a tea kettle
• If rising in frequency, an explosion may be
imminent.
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Shutting Off Gas Service
• Most residential gas is supplied through a
meter connected to the distribution system
and flow can be stopped by closing and flow can be stopped by closing
quarter-turn valve.
• If an LPG tank is outside, closing the valve
will stop the flow.
• When shut off, use a lockout tag.
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Fires Involving Electricity
• Greatest danger is electrocution.
• Only Class C extinguishers should be
used on energized equipment.used on energized equipment.
• Once electricity is disconnected, most are
controlled as a Class A fire.
• Turn off electricity on structure fires.
• May use breaker box or power company
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Electrical Fire Suppression
• Best approach is to wait until power is disconnected.
• If immediate action is required, use Class C agents only.
• For electronic equipment use halon or CO2.
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Power Lines and Transformers
• Do not attack until power is disconnected.
• Transformers may contain polychlorinated
biphenyls (PCBs).biphenyls (PCBs).
• Water may cause the hot oil to boil over.
• Large transformers may require foam.
• CO2 and dry chemical may be used from
above in underground vaults.
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Summary (1 of 3)
• Every fire fighter must master the use of
hose lines to apply water to a fire.
• An interior fire attack is an offensive • An interior fire attack is an offensive
operation that requires fire fighters to enter
a building and discharge an extinguishing
agent (usually water) onto the fire.
• Large handlines can be used for either
offensive or defensive operations.
21
Summary (2 of 3)
• Master stream devices produce high-
volume water streams for large fires.
• Exposure protection is a consideration at • Exposure protection is a consideration at
every fire; however, it is much more
important when the fire is large.
• Vehicle fires are common in most
communities.
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Summary (3 of 3)
• Special tactics must be used when
extinguishing a flammable liquids fire.
• The popularity of propane gas for heating • The popularity of propane gas for heating
and cooking has caused these cylinders to
become commonplace.
• The greatest danger with most fires
involving electrical equipment is the
possibility of electrocution.