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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.

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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.