FFP Ventilation Flashcards
Define Deflagration
An explosive event that occurs during a backdraft when O2 is introduced & mixed w/flammable gases for a fire burning in a confined space that consumed prior available O2
Flashover occurs: surfaces exposed to thermal radiation from fire gases in excess of _F reach ignition temperature simultaneously
1100 F (Results in fire involvement of entire compartment or enclosed space)
_ is defined as a fire in which heat release rate & fire growth are controlled by characteristics of fuel because there’s adequate O2 available for combustion
Fuel limited fire
Fully Developed Stage Occurs (before/after) flashover, resulting in floor to ceiling burning within the compartment
After
During _ Stage heat is transferred from fire & combustion products are pyrolyzing adjacent fuel sources. Rollover occurs
Growth
Define Pyrolysis
Transformation of materials into their basic compound when subjected to heat. Contents continue to off-gas & add to flammable fuel load as long as material subjected to elevated temperatures
Rollover indicates that fire conditions are rapidly deteriorating & _ may be imminent
Flashover
Define Ventilation Induced Flashover
Initiated by intro of O2 into a pre-heated, fuel rich (smoke filled), O2 deficient area. More prevalent w/modern content fires.
What is a priority when entering a fire area via window
Close the door to that room/area in order to isolate area being searched from fire area
Ventilation for Extinguishment
Coincides w/Eng extinguishing fire. Replaces “Vent for Fire”
Vent for Search
Facilitates movement of a FF into an area to conduct a search for victims. Replaces “Vent for Life”
Progression of Modern Content Fire Development Curve
Incipient stage, Rapid Growth consuming O2 quickly, Earlier O2 limited Decay stage (Remains in Decay if NO O2 added to fire area). If O2 added- rapid 2nd growth stage followed by Ventilation Induced Flashover & transition into fully developed stage. Ends in 2nd decay stage
List some signs that indicate wind driven fire
Smoke & fire venting downward, horizontally, or pulsing from an opening in the bldg.
Any unusual Ventilation profile must be immediately relayed to _
Ladder Officer & IC
Why is it important for Lad Off to notify IC that the door has been controlled to the fire apt
Gives location of fire for Eng, Confirms interior conditions tenable, & Roof FF can now initiate Vertical Ventilation