Chapter 15: Fire Attack Flashcards
Direct attack
Fire stream is applied directly on to the burning fuel
can be direct or indirect
When to do direct attack
- Stream can reach seat of fire
- thermal balance is stable and products of combustion are in uppermost levels of structure
- fires fuel is not enclosed
- most of the fuel is in the smoldering stage
- you cannot achieve direct ventilation
Indirect Attack
Using the principles of water to steam conversion and expansion to knock down a free burning fire by absorbing heat energy
Indirect interior attack
Bank fire stream off ceiling or wall in an attempt to cool down the atmosphere or reduce the intensity of fire.
short bursts in general direction of fire
reasons to use a Indirect exterior attack (defensive)
Super heated atmosphere- first control and reduce heat with in structure by deflecting streams towards the seat until proper ventilation is set up
- second, once ventilation is set up proceed inside to the seat of the fire for complete control
do not do if crews or pts are inside
Combination Attack
a use of both direct and indirect attacks to control and extinguish
Transitional Attack(offensive exterior)
AN Offensive attack Starting from the exterior w/ indirect hand-line op. into fire compartment to initiate cooling while transitioning to an interior attack in coordination with ventilation
Combi from interior
FOG FOG FOG PENCIL PENCIL PENCIL to cool surfaces ant atmosphere then close door; allow atmosphere to cool repeat until such time as direct attack can be made
Read SMOKE
Volume: alot of smoke = BIG fire, fire progession
Velocity: moves fastest from hottest point= heat & PRESSURE, angry smoke = flashover
Color: can tell you whats burning
Density: how much fuel is involved, smoke is a fuel, = black fire or flash over
FIRE STREAM
solid, fog, broken
Defined as a stream of water or other extinguishing agent after it leaves a nozzle until it reaches the desired point
solid stream
fixed orifice or smooth board nozzle: compact stream with mix penetration, more nozzle reaction
Pro: grater visibility,better reach & penetration, can have reduced nozzle pressure per liter, thermal layering less likely to be disturbed
Con: Cannot be used w/ foam, fixed pattern, less heat absorption, conductive
Affected by: Air Friction, Wind, Gravity
Fog Stream (45-80’)
Stream comprise of very fine water droplets
Affected by: Velocity,Gravity, Pattern,Air friction, wind
Stream effectiveness & break over
Streams are effective until the lose forward velocity (break over) the stream loses its original shape and cannot maintain height.
Max Stream
Reach=30-34’
Height= maxed out @75’
Broken Stream
Course water droplets: good heat adsorption and penetration
15-45’
basements, attics, wall spaces
5 causes of defective streams
Insufficient pressure Too much pressure Defective tip Air in line Twist/kink in hose near pipe
Atmosphere testing
When you enter look for thermal layering,if you feel the heat
go full fog into and give it a quick shot if no water droplets come down the environment is super heated
Line selection
Type of fire & fuel volume needed Man power reach time
When advancing a hose line
-select line from transverse
-read smoke(look for back-draft/flash-over)
-All FF to be in safe & ready position before opening a door
-Check door for heat
- Bleed line and have correct nozzle setting
- try not to block ventilation openings
- flake out hose
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How can you tell if a fire stream is working
Darkening down
White smoke/white steam
Rapid temp fluctuation
Decreased visability
What is a master stream
A large caliber device used primarily for defensive straegies
3 types Portable, fixed, elevated fixed
Master stream appliances flow rates
70 kpa loss
- Deck/Deluge Gun:500kpa(new) 700kpa(old): 2650lpm
- Quick attack: pre-connected 5 lengths of 65mm: 3 settings 950,1400, 1900LPM: 1034kpa
- Ladder 7000lpm @ 1000kpa
Exposures
- Near by structures, combustibles, or equipment that could be consumed by fire.
Interior & Exterior : protect with fog or broken streams
