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16. Fire Hose, Nozzles, Streams, and Foam. Objectives (1 of 4). Describe fire hydraulics. Describe how to prevent water hammers. Describe the types of hoses used in the fire service. Describe how a hose is constructed. Objectives (2 of 4). Describe how to clean and maintain a hose. - PowerPoint PPT Presentation
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16Fire Hose, Nozzles, Streams, and Foam
16
Objectives (1 of 4)
• Describe fire hydraulics.
• Describe how to prevent water hammers.
• Describe the types of hoses used in the fire service.
• Describe how a hose is constructed.
16
Objectives (2 of 4)
• Describe how to clean and maintain a hose.
• Describe how to inspect a hose.
• Describe hose appliances.
• Describe how to lay a supply line.
16
Objectives (3 of 4)
• Describe how to load a hose.
• Describe how to connect a hose to a water supply.
• Describe how to carry and advance a hose.
• Describe the types and designs of nozzles.
16
Objectives (4 of 4)
• Describe pressure effects and flow capabilities of nozzles.
• Describe how foam works.
• List the types of foam.
• Describe how to make foam.
• Describe how to apply foam.
16
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)
16
Pressure
• Amount of energy in a body or stream of water
• Measured in pounds per square inch (psi)
• Required to push water through a hose or to lift water up to a higher level
• Pump adds energy to a water stream, causing an increase in 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.– With any combination of flows and diameter,
friction loss is proportional to the distance
16
Elevation Pressure
• Elevation affects water pressure.
• Elevated water tanks supply pressure to pipes due to elevation.
16
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.
16
Functions of Fire Hoses• Supply hose
– Carries water to the engine– May come from a hydrant or another engine– Carries large quantities at lower pressures
• Attack hose– Carries water from engine to the nozzle– Carries water from engine to master streams– Carries water to standpipe system
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Sizes of Hose (1 of 3)
• Small-diameter hose– 1" to 2" in diameter– Used as attack lines– Each section is usually
50' long.
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Sizes of Hose (2 of 3)
• Medium-diameter hose– 2 ½" or 3" in diameter– Used as attack line or supply line
• Master stream and fire department connections often use 3" hose.
– Each section is usually 50' long.
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Sizes of Hose (3 of 3)
• Large-diameter hose– 3 ½" to 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
• 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
– Attached to outer covering
16
Hose Couplings
• Used to connect individual lengths of hose
• Used to connect hose line to hydrants, valves, nozzles, fittings, and appliances
• Two types– Threaded– Nonthreaded (Storz-type)
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Threaded Couplings (1 of 2)
• Used on most hose up to 3"
• A set consists of male and female
• 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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Threaded Couplings (2 of 2)
• 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
• Couplings are mated face-to-face.
• Adapters
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Attack Hose (1 of 4)
• 1 ½" and 1¾"– Most common attack line– Both use 1½" couplings– Can be operated by one fire fighter– Most common preconnect lengths of 150' to
350'– 1½" generally flows 60–125 gpm– 1¾" generally flows 120–180 gpm
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Attack Hose (2 of 4)
• 2 ½" hose– Used to attack larger fires– Generally flows about 250 gpm– Takes at least two fire fighters inside a
building– Can flow up to 350 gpm
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Attack Hose (3 of 4)
• 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
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Attack Hose (4 of 4)
• Forestry hose– Typically 1" or 1½"– Used for wildland and ground fire
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Supply Hose• Used to supply attack
engine• Ranges from 2½" to
6"• Larger diameter is
more efficient• Two types
– Soft suction– Hard suction
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Types of Damage to Hose (1 of 4)
• Mechanical– Abrasion– Broken glass and
sharp objects– Abrasion from hose
reloaded dirty– Vehicles running over – Couplings being
damaged or dragged
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Types of Damage to Hose (2 of 4)
• 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.
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Types of Damage to Hose (3 of 4)
• Chemicals– Encountered at many incidents, including
vehicle fires and accidents– Wash hose as soon as possible with
approved detergent.
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Types of Damage to Hose (4 of 4)
• Mildew– Grows on fabrics in warm, moist conditions– Feeds on natural fibers and causes the hose
to rot– Synthetic fibers and resist 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
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Hose Appliances (1 of 9)
• Wyes– Split the stream into
two hose streams– Commonly split a 2 ½"
hose into two 1 ½"– Gated wyes have two
quarter-turn valves.
16
Hose Appliances (2 of 9)
• Water thief– Similar to a gated wye– Has an additional 2 ½”
outlet
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Hose Appliances (3 of 9)
• 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
16
Hose Appliances (4 of 9)
• Adaptors – Used to connect same
size hoses but with dissimilar threads
– Are double-female or double-male
16
Hose Appliances (5 of 9)
• Reducers– Used to attach smaller
hoses to larger hoses– Commonly used to
reduce a 2½" hose to a 1½" hose
16
Hose Appliances (6 of 9)
• Hose jacket– Used to stop a leaking
section of hose– Consists of a split
metal cylinder that fits tightly over the hose
16
Hose Appliances (7 of 9)
• Hose roller– Used to protect a line
being hoisted over an edge
– Prevents chafing and kinking
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Hose Appliances (8 of 9)
• 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 9)
• 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
– 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
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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 4)
• 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
16
Supply Hose Evolutions (2 of 4)
• Four-way hydrant valve– Used when a supply engine may be needed
at the hydrant– When four-way is placed on the hydrant,
water initially flows.– A second engine can then hook to the four-
way and boost pressure to the supply hose.
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Supply Hose Evolutions (3 of 4)
• Reverse hose lay– Hose is laid from the
fire to the hydrant.– Used when attack
engines begin attack without a supply line
– Later arriving company stops at the attack engine and lays line to the hydrant.
16
Supply Hose Evolutions (4 of 4)
• Split hose lay– Performed by two
engines– Used when hose must
be laid from two directions
– Requires coordination by two-way radio
16
Loading Supply Hose (1 of 4)
• 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.
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Loading Supply Hose (2 of 4)
• Flat hose load– Limits wear on hose
edges– Used with single and
split hose beds
16
Loading Supply Hose (3 of 4)
• 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 wavelike manner– Has fewer sharp bends
16
Loading Supply Hose (4 of 4)
• 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 are 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.
16
Preconnected Attack Lines
• Intended for immediate use
• A preconnected hose line with a nozzle attached
• Commonly 1¾" in diameter and 150' to 250' in length
• May also be 2½"
• A variety of loads can be used.
16
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 3)
• Advanced in two stages
• Flake extra hose in a serpentine pattern.
• Once the hose is ready: – Signal pump operator
to charge line.
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Advancing an Attack Line (2 of 3)
• Open nozzle slowly to bleed out air.
• Set nozzle to appropriate stream.
• Ensure personal protective equipment is secure.
• Check partner’s equipment.
• Start breathing from SCBA.
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Advancing an Attack Line (3 of 3)
• 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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Advance a Hose Up a Stairway
• Arrange an adequate amount of extra hose close to the bottom of the stairs
• Shut down the hoseline while advancing
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Advance a Hose Down a Stairway
• Keep as low as possible to avoid heat and smoke
• Never advance towards a fire unless the hose line is charged
• Move carefully
16
Advance a Hose Up a Ladder
• Should be done before the line is charged
• Additional hose should be fed up the ladder
• Secure the hose to the ladder with a hose strap
16
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.
16
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.
16
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.
16
Nozzles
• Give fire streams shape and direction• Classified into groups:
– Low-volume– Handline– Master stream
• Shut-offs– Quarter-turn valve– Rotary control valve
16
Smooth-Bore Nozzles (1 of 3)
• Consist of shut-off valve and smooth bore tips
• Fit handlines and master stream devices
16
Smooth-Bore Nozzles (2 of 3)
• Advantages:– Longer reach than combination fog nozzle– Capable of deeper penetration into burning
materials– Operate at lower pressures– Extinguishes fire with less air movement
16
Smooth-Bore Nozzles (3 of 3)
• 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
16
Fog Stream Nozzles (1 of 4)
• Produce fine droplets of water
• Absorb heat quickly
16
Fog Stream Nozzles (2 of 4)
• 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
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Fog Stream Nozzles (3 of 4)
• 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
16
Fog Stream Nozzles (4 of 4)
• 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.
16
Other Types of Nozzles
• Piercing nozzle• Cellar nozzle• Water curtain nozzle
16
Nozzle Maintenance and Inspection
• Nozzles should be:– Inspected regularly– Checked after each use– Kept clean and clear of debris
• Inspect fog nozzle fingers
16
Summary (1 of 2)
• Fire hydraulics deal with properties of energy, pressure, and water flow as related to fire suppression.
• Fire hoses are used for two main purposes: supply and attack.
• Fire hoses range in size from 1 inch to 6 inches in diameter.
• Fire hoses should be regularly inspected and tested following the procedures in NFPA 1962.
• Hoses that are not properly maintained can deteriorate over time and eventually burst.
• A hose appliance is any device used in conjunction with a fire hose for the purpose of delivering water.
16
Summary (2 of 2)
• Rolled hose is compact and easy to manage. • Hose evolutions involve specific actions that are
assigned to each member of a crew, depending on their riding positions on the apparatus.
• Nozzles are attached to the discharge ends of attack lines to give fire streams shape and direction.
• Nozzles are classified into three categories: low-volume nozzles, handline nozzles, and master stream nozzles.
• Firefighting foam can be used to fight several types of fires and to prevent the ignition of materials that could become involved in a fire.