Types of Attack
Intent is to cool the surface of a burning or pyrolyzing object to below its auto-ignition temperature, and once achieved visible, flaming combustion ceases.
What is a direct attack?
Coordinated inlet and outlet openings with effective water application
Purposeful management of flow path
What is horizontal ventilation?
Type of reaction that absorbs heat instead of releasing it
What is an endothermic reaction?
One of the most critical tasks to be conducted at an early stage of a structure fire.
What is a 360-degree walkaround/size-up?
The temperature at which water will convert to steam.
100C
Intent is to maximize steam production to absorb energy from the hot smoke and flaming combustion, dilute and reduce the flammable range of the gases in smoke, and displace air until fire is suppressed.
What is an Indirect Attack?
Buoyant smoke exhausted from opening located above level of fire utilizing the stack effect, denser fresh air entrained via horizontal inlets
What is vertical ventilation?
The rate of expansion that water will turn into steam at 100C.
What is 1700x?
3 things to look for when looking into the entrance of a structure fire
What are life, fire, and layout?
NFPA states this temperature as the threshold of human tenability.
To control fire extension and limit fire growth to building of origin.
What is exposure control/protection?
Fan used to create pressure differential, influencing the flow of air and smoke from inlet to exhaust
Floor plans with many rooms and closed door offer best opportunity for benefit
Open floor plans with high ceilings not effective
What is PPV?
This happens when steam expands within a fire compartment, shrinking the flammability range until at some point it no longer supports combustion.
What is air displacement?
What is wetting the door?
The lens of an SCBA facepiece tends to fail at this temperature
500F
Applying water into fire compartment from exterior before making entry for direct attackUsed with straight stream at a steep angle aimed at ceiling of room (through lower portion of opening to allow steam and gases to ventilate)
What is "Hard From the Yard" or transitional attack?
Create positive pressure in the non-fire area greater than the pressure in fire area to limit fire and smoke propagation
What is PPP or PPI?
When heat is absorbed until the temperature of the water and the hot gas layers equalize
What is thermo equilibrium?
Factor concerning the door influencing the way you flake out your hose.
What is swing of the door?
The average temperature of a house fire at eye level
600F
Technique to reduce possible flashover/backdraft conditions. NOT an extinguishment Technique
What is gas cooling?
Hose stream employed at opening, creating negative pressure differential behind nozzle
Entrains smoke and discharges it from room, while drawing in replacement air from other openings
What is hydraulic ventilation?
Amount of energy needed to for water to change matter from liquid to vapor.
What is the latent heat of vaporization?
Easy way to restrict fire growth from outside.
Close doors and windows (ventilation inlets)
Temperature range associated with flashover
1000-1500F