16 Fire Hose, Nozzles, Streams, and Foam
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Fire Hose, Nozzles, Streams, and Foam
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Objectives (1 of 2)
• Describe how to prevent water hammers.• Describe how a hose is constructed.• Describe the types of hoses used in the fire service.• Describe how to clean, maintain and inspect hose.• Describe how to note a defective hose.• Describe how to roll hose.• Describe how to lay a supply line and connect a hose to a
water supply.• Describe how to load hose.• Describe how to carry and advance hose.
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Objectives (2 of 2)
• Describe the types and designs of nozzles.
• Describe pressure effects and flow capabilities of nozzles.
• Describe how foam works.• List the types of foam.• Describe how to make and apply foam.
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Fire Hydraulics
• Deal with properties of energy, pressure, and water flow as related to fire suppression.
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Flow
• Volume of water that is being moved
• Measured in gallons per minute (gpm)
• Metric measured in liters per minute (lpm)
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Pressure
• Amount of energy in a body or stream of water
• Measured in pounds per square inch (psi)
• Metric measured in kilopascals (kPa)• Required to push water through a hose
or to a higher level• Pumps usually provide the pressure.
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Friction Loss
• Loss of pressure as water moves through a pipe or hose
• Loss represents the energy required to push the water.– Greater flow in same hose, greater friction loss– Smaller hose with same flow, greater friction loss– All else equal, loss proportional to distance
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Elevation Pressure
• Elevation affects water pressure.• Elevated water tanks supply pressure to
pipes due to elevation.• Difference between nozzle elevation
and engine elevation affects pressure.– Hoses laid downhill have greater pressure.– Hoses laid up stairs will have less
pressure.
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Water Hammer
• Surge in pressure caused by sudden stop in the flow of water
• Shock wave is transmitted back through the hose.
• Can damage hose, couplings, and plumbing
• To prevent, open and close valves slowly.
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Functions of Fire Hoses
• Attack hose– Carries water from engine to the nozzle– Carries water from engine to master streams– Carries water to standpipe and sprinkler systems
• Supply hose– Carries water to the engine– May come from a hydrant or another engine– Carries large quantities at lower pressures
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Sizes of Hose• Small Diameter Hose
– 1" to 2 " in diameter– Used as attack lines– Each section is usually
50' long
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• Medium Diameter Hose– 2 1/2" or 3" in diameter– Used as attack line or supply line
• large handlines usually use 2 1/2“.
• master stream and fire department connections often use 3" hose.
– Each section is usually 50' long.
• Large Diameter Hose– 3 1/2" or 6" in diameter– Standard diameter is 4" or
5“.– Standard length is 50' or
100' long.
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Pressure Testing
• Attack hose– Tested annually– Tested to 300 psi– Designed for use up to 275 psi
• Supply hose– Tested annually– Tested to 200 psi– Designed for use up to 185 psi
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Hose Construction (1 of 2)
• Fire hose constructed of inner waterproof liner and one or two outer layers
• Outer layers– Provide strength for high pressures– Made from synthetic fibers– Provide some abrasion protection
• Can be double jacket hose• Can be rubber-jacket hose
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Hose Construction (2 of 2)
Inner waterproof liner– Prevents water leakage– Provides smooth surface
to reduce friction– Usually made of
• synthetic rubber compound• thin flexible membrane
– Attached to outer covering
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Hose Couplings
• Used to connect individual lengths of hose
• Used to connect hose to hydrants, valves, nozzles, and fittings
• Two types– Threaded– Nonthreaded (Storz-type)
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Threaded Couplings• Used on most hose up to 3"• A set consists of male and
female couplings.• Male threads are on the
outside.• Female threads are on the
inside.• Female couplings swivel.• Fire hose has a male on one
end and a female on the other.
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• Higbee indicators indicate proper thread alignment.
• Female couplings have a gasket to prevent leaks and require periodic replacement.
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Storz-type Couplings• Has neither male nor female
ends• Most often used in large
diameter hose• Couplings are mated face-to-
face and turned clockwise one third.
• Adapters are used to connect to threaded couplings.
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Attack Hose (1 of 3)
• 1 1/2" and 1 3/4"– Most common attack line– Both use 1 1/2" couplings– Can be operated by one fire fighter– Most common preconnect lengths of 150'
to 350'– 1 1/2" generally flows 60-125 gpm– 1 3/4" generally flows 120-180 gpm
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Attack Hose (2 of 3)
• 2 1/2" hose– Used to attack larger fires– Generally flows about 250 gpm– Takes at least two fire fighters inside a
building– Weight per 50' section
• Without water, weighs 30 pounds• With water, weighs about 200 pounds
– Can flow up to 350 gpm
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Attack Hose (3 of 3)
• Booster hose– Usually carried on a hose reel with 150' to 200’– Made of rubber with steel wire to give shape– Can be advanced by one fire fighter– 1" line flows 40-50 gpm– Used for small outdoor fires and trash dumpsters
• Forestry hose– Typically 1" or 1 1/2"– Used for grass, brush, or forestry fires– Extremely maneuverable
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Supply Hose
• Used to supply attack engine
• Ranges from 2 1/2" to 6"• Large diameter is more
efficient than 2 1/2"• Two types
– Soft suction– Hard suction
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• Mechanical– Abrasion from road surfaces– Broken glass and sharp objects– Abrasion from hose reloaded dirty– Vehicles running over it– Couplings being damaged– Couplings being dragged
Types of Damage to Hose (1 of 3)
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Types of Damage to Hose (2 of 3)
• Heat and cold– Direct contact from fire– Burning coals and embers– Hot surfaces such as heating units and
exhaust pipes– Freezing can rupture inner liner and break
outer liner fibers.– Lines may be frozen or encased in ice.
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Types of Damage to Hose (3 of 3)
• Chemicals– Encountered at many incidents, including vehicle fires
and accidents– Wash hose as soon as possible with approved detergent.
• Mildew– Grows on fabrics in warm, moist conditions– Feeds on natural fibers and causes the hose to rot– Modern hose has synthetic fibers and resists mildew.– Rubber-covered hose fibers are protected from mildew.
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Cleaning, Maintaining, and Inspecting Hose
• Cleaning and maintaining hose– Clean contaminated hose
• Hose inspections– Perform quarterly and after each use
• Hose records – Written history of each length of hose
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Hose Appliances (1 of 10)
• Wyes– Split the stream into
two hose streams– Commonly split a
2 1/2" hose into two 1 1/2"
– Gated wyes have two quarter turn valves.
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Hose Appliances (2 of 10)
• Water thief– Combines two hose lines into one– Has a 2 1/2" inlet, a 2 1/2" outlet, and two
1 1/2" outlets
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Hose Appliances (3 of 10)
• Siamese– Combines two hose lines into one– Has two female inlets and one male outlet– Often used on engine outlets, master
streams, and fire department connections
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Hose Appliances (4 of 10)
• Adaptors – Used to connect
same size hoses but with dissimilar threads
– Are double-female or double-male
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Hose Appliances (5 of 10)
• Reducers– Used to attach
smaller hoses to larger hoses
– Commonly used to reduce a 2 1/2" hose to a 1 1/2" hose
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Hose Appliances (6 of 10)
• Hose jacket– Used to stop a
leaking section of hose
– Consists of a split metal cylinder that fits tightly over the hose
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Hose Appliances (7 of 10)
• Hose roller– Used to protect a
line being hoisted over an edge
– Prevents chafing and kinking
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Hose Appliances (8 of 10)
• Hose clamp– Used to
temporarily stop the flow of water in a hose:
• so the hydrant can be opened
• that has burst
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Hose Appliances (9 of 10)
• Master stream devices– Large capacity
nozzles supplied by two or more lines
– Include deck guns and portable nozzles
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Hose Appliances (10 of 10)
• Valves– Control the flow of
water through hose or pipe
– Must be opened and closed slowly
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Types of Valves (1 of 2)
• Ball valves– Used on nozzles,
gated wyes, and engine discharges
– Consist of a ball with a hole in it
– When hole is in-line with inlet and outlet, water flows.
– When ball is rotated, flow shuts off.
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Types of Valves (2 of 2)
• Gate valves– Used on hydrants and
sprinklers– Rotating spindle causes
gate to move across opening
• Butterfly valves– Used on large pump
intake– Opened by rotating
handle one-quarter turn
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Hose Rolls
• Hose roll is an efficient way to transport a single section of fire hose.
• Hose can be rolled in many different ways, depending on how it will be used.
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Supply Hose Evolutions (1 of 3)
• Forward hose lay– Allows first engine to
establish a water supply without assistance
– Places the attack engine close to the fire
– Can be used with medium or large diameter hose
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Supply Hose Evolutions (2 of 3)
• Reverse hose lay– Hose is laid from the fire
to the hydrant.– Often used when attack
engines begin attack without a supply line
– Later arriving company stops at the attack engine and lays line to the hydrant.
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Supply Hose Evolutions (3 of 3)
• Split hose lay– Performed by two
engines– Used when hose
must be laid from two directions
– Requires coordination by two-way radio
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Loading Supply Hose (1 of 2)
• Hose can be loaded in different ways, depending on the way the hose is planned to be laid out.
• Learn the specific hose loads used by your department.
• Flat hose load– Limits wear on hose edges– Used with single and split hose beds
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Loading Supply Hose (2 of 2)
• Horseshoe hose load– Forms a U-shape– Cannot be used for large diameter hose– Causes more wear on hose edges– Tends to lay out in a wave-like manner– Has fewer sharp bends
• Accordion hose load– Easy to load– Creates sharp bends in the hose– More wear than the flat load– Not recommended for large diameter hose
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Connecting an Engine to a Water Supply
• Supply hose must be used to deliver water from the hydrant to the engine.
• In most cases, soft suction hose is used to connect directly to a hydrant.
• Connection can also be made with a hard suction hose.
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Attack Line Evolutions
• Attack lines used to deliver water from an attack engine to a nozzle.
• Most engines are equipped with preconnected attack lines.
• Additional supply of attack hose is usually carried in a hose bed or compartment that is not preconnected.
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Preconnected Attack Lines
• Intended for immediate use
• A preconnected hose line with a nozzle attached
• Commonly 1 3/4" in diameter and 150' to 250' in length
• May also be 2 1/2"
• A variety of loads can be used.
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Wye Lines
• May be necessary to first advance a large diameter line and then split it into two attack lines– Accomplished by attaching a gated wye or
a water thief to the end of the large diameter line
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Hose Carries and Advances
• Best technique for carrying and advancing fire hose depends on size of hose, distance it must be moved, and number of fire fighters available.
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Working Hose Drag
• Used to deploy hose from a hose bed and advance the line a short distance
• Several fire fighters may be needed for the task.
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Shoulder Carry
• Used to transport full lengths of hose over a longer distance
• Useful for advancing a hose line around obstructions
• Requires practice and good teamwork
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Advancing an Attack Line (1 of 2)
• Advanced in two stages• Flake extra hose in a serpentine
pattern.• Flake out with lengths parallel to
front of building.• Signal pump operator to charge
line.• Open nozzle slowly to bleed out
air.• Set nozzle to appropriate stream
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Advancing an Attack Line (2 of 2)
• Ensure personal protective equipment is secure.• Check partner’s equipment.• Start breathing from SCBA.• Stand to the side when opening the door.• Stay low as you move in.• If you can’t see, feel as you go.• Communicate as you advance.• Two members should be at the nozzle and one at the
door feeding hose.
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Connecting Hose Lines to a Standpipe System
• Fire fighters connect attack lines to outlets inside.
• Fire fighters outside supply water to the fire department connections.
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Advancing an Attack Line from a Standpipe Outlet
• Standpipe outlets are often located in stairways.
• Before charging the hose line, the hose should be flaked out on the stairs going up from the fire floor.
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Replacing a Defective Section of Hose
• A burst hose line should be shut down as soon as possible.
• A hose clamp can be used to stop the flow in an undamaged section of hose upstream from the problem.
• Replace the damaged section and replace it with two sections of hose.
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Draining and Picking Up Hose
• The hose must be drained of water to be put back in service.
• Lay hose straight on a flat surface, then lift one end to shoulder level.
• Fold hose back and forth over your shoulder.
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Unloading hose
• Disconnect gate valves and nozzles.• Grasp hose end and pull from engine.• When coupling comes off, disconnect hose.• Repeat until all hose bed is empty.• Brush off dirt and debris from each side.• Sweep out hose bed.• Roll hose into donut rolls. • Store hose on racks.
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Nozzles
• Give fire streams shape and direction• Classified into groups:
– Low volume– Handline– Master stream
• Shut offs– Bale closes a quarter-turn valve– Rotary control valves
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Smooth Bore Nozzles• Consist of shut off valve and
smooth bore tips• Fit handlines and master stream
devices
• Advantages:– Longer reach than fog nozzle– Capable of deeper penetration
into burning materials– Operate at lower pressures– Extinguishes fire with less air
movement
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• Disadvantages:– Do not absorb heat as readily
as fog streams– Not as effective as fog
streams for hydraulic ventilation
– Cannot change setting to produce a fog pattern
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Fog Stream Nozzles• Produce fine droplets of water• Absorb heat quickly and efficiently• Advantages:
– Create a variety of stream patterns
– Can be used to create a water curtain to protect fire fighters from extreme heat
– Can be used to exhaust smoke and gases through hydraulic ventilation
• Disadvantages:– Move large volumes of air, which can
result in a sudden heat inversion that pushes hot steam and gases onto fire fighters
– If used incorrectly, can push fire into unaffected areas
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• Types of fog stream nozzles:– Fixed gallonage: deliver a preset
flow in gpm at the rated discharge pressure.
– Adjustable gallonage: allow the operator to select a desired flow.
– Automatic adjusting: deliver a wide range of flows.
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Other Types of Nozzles
• Piercing nozzle– Makes holes in automobile sheet metal, aircraft, or
building walls
• Cellar nozzle– Fights fires in cellars and other inaccessible
places
• Water curtain nozzle– Delivers a flat screen of water to form a protective
sheet of water
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Nozzle Maintenance and Inspection
• Nozzles should be:– Inspected regularly– Checked after each use– Kept clean and clear of debris
• Inspect fog nozzle fingers
• Send nozzles to competent technicians for repairs
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Foam
• Used to fight several types of fires
• Used to prevent ignition of materials
• Used to neutralize hazardous materials
• Produced by mixing foam concentrate with water and air
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Foam Classifications• Class A foam
– Used to fight fires involving ordinary combustible materials– Increases effectiveness of water by reducing the surface
tension of water– Can be added to water streams and applied with several
types of nozzles
• Class B foam– Used for class B fires– Specific foam varies by type of flammable liquid– Separates fuel from the fire– Foam blanket must not be disturbed– Can be applied to flammable liquid spills to prevent fire
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Class A Foam Concentrates
• From 0.1% to 1% solution
• “Wet” foam has good penetration properties.
• “Stiff” foam is more effective when applied for protecting buildings.
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Class B Foam Concentrates (1 of 2)
• Used as either 3% or 6% solution• Types of foams should not be mixed.• Brands of the same foams should not be
mixed.• Incompatible mixtures may congeal and plug
foam systems.• Older foams have environmental hazards.
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Class B Foam Concentrates (2 of 2)
• Protein foams– Made from animal byproducts
– Effective on hydrocarbon fires
• Fluoroprotein foams– Made with same base
materials as protein foam
– Includes a flurochemical surfactant
– Produce fast-spreading membrane
– Provide a greater seal against edges of objects
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• Aqueous film-forming foam (AFFF)– Synthetic base
– Particularly suited for gasoline
– Seals across surface quickly
– Excellent vapor suppression ability
• Alcohol-resistant foam– Properties similar to AFFF
– Won’t dissolve in alcohols and other polar solvents
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Foam Equipment
• Includes proportioning equipment to mix water and foam concentrate
• May be portable or built-in to apparatus
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Foam Proportioners (1 of 2)
• Eductors– Use venturi effect to draw foam into stream– May be built-in to pump plumbing– May be portable and inserted into attack line– Portable is most common
• Used with 1 1/2" hose
• Requires 200 psi of water pressure
• Draws foam from portable containers
• Only 150' of 1 1/2" can be used after eductor
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Foam Proportioners (2 of 2)
• Injectors– Add concentrate to the water stream under pressure– Most work across a range of flow rates and pressures– A metering system takes measurements and adjusts the
injector to the proper amounts.
• Batch mixing– Concentrate poured directly into booster tank
• Premixing– Commonly used in 2 1/2-gallon extinguishers– Extinguisher is filled with foam solution and pressurized.– Some vehicles have large tanks of premixed foam.
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Foam Application Systems
• Types– Portable extinguishers– Hand lines– Master stream devices– Fixed systems
• Foam is applied with a variety of nozzles.
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Foam Application Rates
• Low expansion foam
• Medium expansion foam
• High expansion foam
• Compressed air foam systems (CAFS)
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Foam Application Techniques
• Sweep method (roll-on)– Used on a pool of product on open ground
• Bankshot method (bank down)– Used where there is an object to deflect
stream
• Rain-down method– Lofts foam into air to gently fall on surface
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Other Considerations
• Request back up resources to ensure foam supply is uninterrupted.– Manufacturers have emergency supplies
available.
• Specialized apparatus may be available.– Carry large quantities of foam concentrate and
water.– Use remote control nozzles for delivery.
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Summary
• Fire hydraulics deals with energy, pressure, and water flow.
• Fire hoses vary in size and construction.• A hose appliance is any device used with fire hose to
deliver water.• Fire hose evolutions are standard methods of working
with fire hose.• Nozzles give fire streams shape and direction.• Foam can be used to extinguish a variety of fires or to
prevent their ignition.
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