1 Flashcards
RECEO VS
Rescue Exposure Confinement Extinguishment overhaul ventilation salvage
What is a Flashover?
The point when all surfaces and objects within a space reach their ignition temperature and simultaneously ignite
What is a Backdraft?
An explosive event caused by the introduction of oxygen into an oxygen deficient high heat smoldering fire. Typically occurs during the decay stage after the fire has consumed all available oxygen within a compartment.
What are some warning signs of a backdraft?
Dense smoke with no visible flames in a tightly closed compartment, black smoke pushing around closed doors or window frames, glass stained with smoke condensation and pulsating from the fires pressure, reversal of air movement pulling smoke back into a building through a doorway
What is the difference between modern and legacy construction?
Modern is man made materials, plastics synthetics, polyurethane, and polyester. Legacy is referred to as “traditional materials” consist of natural materials such as cotton l, wicker, solid wood, and, dimensional lumber
What type has a higher HHR or Heat release rate modern or legacy construction?
Modern materials have a higher HRR, when a fire involves these materials temperatures rise quickly and flashover can occur sooner than fires fueled by legacy materials.
What are the four inherent characteristics of smoke?
Volume, velocity, density, and color
What does the volume of smoke leaving a structure indicate?
The amount of fuel that is “off gassing” within a given space. A fire fed by sufficient air will emit very little visible smoke and a fire in a underventilated building building can produce a large volume of smoke.
In what way does smoke volume relate to smoke velocity?
When smoke has filled an inadequately ventilated container, pressure begins to build. In this way smoke volume relates to smoke velocity
What does smoke velocity leaving a structure give ffs insight to?
To the fires location relative to the smoke exhaust point and the status of the fires flow path. As smoke expands and travels up the interior walls across the ceiling and through open doors the buildings materials and contents absorb heat decreasing the smokes velocity
What does static smoke indicate?
A non growing fire with inadequate oxygen. Moving smoke indicates a growing fire with sufficient oxygen
What is optical density?
How difficult it is to see through the smoke. The greater the smoke density the higher the likelihood for a hostile fire event such as flashover or rapid fire spread.
What does the color of smoke indicate
The material makeup of burning fuel. Typically the darker the smoke the more volatile the fire.
What color smoke does a fire in the incipient stage typically produce?
White smoke as the fuel off gases moisture and water vapor
What does gray smoke indicate?
Slowing fire growth as the availability of fuel decreases.
What color does an under ventilated fire usually normally produce?
Brown or black smoke
What can brown smoke indicate?
Under ventilated fire or a fully developed fire is feeding off a wood source. This can mean in wood framed buildings a fire is weakening the buildings structural integrity, creating a risk of collapse
What does black smoke normally indicate?
Heavy fuel loads that are not being fully consumed. Can result from the burning of manmade materials such as petroleum products rubber and many plastics
What is VSP or victim survivability profiling?
Likelihood of a victims rescue potential. Also less commonly referred to as occupant survivability profiling
What three ways can an evacuation order be signaled? Or combined by all three ways at once
The order may be given verbally, signaled over the radio with evacuation tones, blasted over on scene apparatus airhorns, or a combination of all three.
15 seconds for air horns sounding and evacuation tones if they do those
What is the required flow rate for most residential fires?
100-200 gpm making the 1 3/4 an appropriate selection for these fires
How much personnel does it take to advance a 2 1/2?
Often requires two companies and up to 6 firefighters
Stretching short results in?
Delayed extinguishment, fire growth and possible extension, delayed search operations, and reduced survivability of trapped occupants
What is the formula for estimating the stretch?
Setback+ width of the building+ length of the building+ 1/2 length (25ft) per floor+ 1 length at the point of attack
What is the average residential roadway width?
12ft
How big is the modern residential driveway?
12ft wide x 25 ft long
What is the length and width of average sedan or sport utility vehicle?
6ft wide by 15ft long
How much ft of hose should personnel estimate to reach above or below the level of entry?
25ft
What are some ways you can minimize the number of lengths required and probed for rapid hose line positioning?
A well hole stretch, a ground ladder stretch, a utility rope hoisted up the buildings exterior.
What should firefighters do when stretching dry hose lines through doors?
Firefighters must chock all doors through which they stretch dry hose lines to prevent the hose from running under the door. The preferred method is to chock doors low so personnel can quickly remove chocks while retreating under advancing fire conditions
What did John freeman recommend that smooth bore orfices not exceed?
Half the diameter of the hose to which they are affixed
What is the maximum nozzle reaction firefighters can effectively handle?(1ff,2ff,3ff)
1ff- 60 lbf
2ff- 75 lbf
3ff- 95 lbf
What does NFPA 1964 state for automatic combination nozzles?
Allows a pressure variance of _+ 15 psi from their rated pressure. This variance creates obvious issues with flow and stream velocity. Due to this variance personnel should consider avoiding automatic combination nozzles for master streams particularly when combating large volume fires
What is the formula used to find stream velocity?
12.14 x (square root NP)= ft\s
What factors affect air entrainment?
All fire streams entrain air. The length, movement, and width of the stream influence how much air a fire stream entrains. Solid stream and straight stream had comparable results throughout the air entrainment experiments. The longer the fire stream, the more air it entrains. Moving the fire stream also increases the amount of air it entrains.
How far should the nozzle ff place the nozzle from the window when hydraulically ventilating? And white what steam and what percent of the window covered?
2 feet away from the window.
Wide fog
80% of ventilation opening covered
With no fire evident, heat increasing to 800 F or more at the ceiling level and thick black smoke banking down near the floor, interior crews must recognize the compartment is entering what conditions?
Pre flashover
What should the nozzle FF do until the entrance is confirmed?
The nozzle ff should maintain control of the shoulder load until the entrance is confirmed.
What is an engine company drivers ultimate responsibility?
The safe delivery of personnel to and from the scene
In normal circumstances where should the engine driver position the engine on a reported house fire?
Driver must position the engine to create the most direct access for advancing attack hose lines to the seat of the fire while allowing the truck company to position directly in front of the structure.
When the tank level reaches what capacity must the engine driver notify the officer when he/she is at?
1/2 tank
What should be done before charging additional attack hose lines?
Establish a water supply
In what cases may charging a line be required before establishing a water supply?
Exposure protection, line to the attic, RIT use, or controlling exterior fires
What should be done if an officer tells an engine driver to charge their line when a water supply has not yet been established?
The engine driver should advise the requesting officer that no water supply has been established
