Chapter 5 - Fire Behavior and Building Construction Flashcards
Four essential elements for a fire
Fuel
Oxidizing agent
Heat
Uninhibited chemical chain reaction
Phenomenon in which combustible material ignites spontaneously without the application of a flame or spark
Auto ignition
Vertical spread of fire on the exterior of a multi-story building from one floor to the floor above
Auto exposure
Initial stage of a fire after ignition
Incipient
Secondary stage of a fire in which it spreads to adjacent combustible materials
Free burning
Transition stage in which exposed surfaces ignite simultaneously and fire spreads throughout the compartment
Flash over
Stage which glowing combustion takes place
Smoldering / decay
Where is flame over observed
In the ceiling layer
What is the primary influence on a fire burning
Oxygen supply
If wins exceed what speed will their role be considered from a tactical standpoint
10 to 20 mph
What is the most common example of fire having an effect on the building and its components
Charring wood
What temperature does aluminum melt around
1200° F
What temperature does aluminum anneal at
350° F
When heated gaseous products of combustion burn when oxygen is introduced into an environment in which the oxygen supply has been depleted due to fire
Backdraft
Movement of hot gases / smoke from areas of high pressure to low pressure
Flow paths
A more accurate description of flame spread
Fire growth
The building problem with regard to fire growth based on location (2)
Hidden
Exposed
The contents problem with regard to fire growth (3)
Furnishings
Interior finish
Mercantile stock
What must be kept away from light fixtures because the heat from the fixture can ignite the paper
Batt insulation with paper facing that is laid in ceilings
Foamed plastic insulation should be protected from exposure to flame by what type of covering
1/2 in gypsum board
What is commonly used as insulating sheathing on wood frame buildings that can support fire in hidden in walls
Combustible fiberboard
What absorbs heat thereby slowing the progress of fire
Lime plaster
What material was substituted for wood sheathing and widely used for interior finishes in low-cost construction
Low density fiber board
What are the three ways in which interior finishes may increase the fire hazard
- Increase fire extension by surface flame spread
- Generate smoke and toxic gases
- Add fuel to the fire contributing to flash over.
What is high density fiberboard called when it punched with holes
Pegboard
What material has ignited after a 1 second application of flame from a butane lighter
Foamed polyurethane
What are four ways to control the problem of fast fire growth
- Eliminating high flame spread surfaces.
- Separating material from the source of combustion.
- Cutting off the extension of the fire.
- Coating materials
Fire retardant surface coatings are effective only if applied how
As specified
In smoke the solid particulates of what give smoke its opaqueness
Carbon
What is the most prevalent toxic fire gas
CO
Harber’s rule states that any exposure in which the concentration is ____ is likely to be dangerous
33,000
A 10 minute exposure to ___ of CO would be hazardous
3500 PPM
What concentration of CO may be fatal after only a few breaths
12,500 PPM
Generation of CO can be up to how many times greater in enclosed voids as in the open
50 times
What chemicals can be released from any transformer by fire or accident and is extremely toxic
Polychlorinated biphenyl. PCB
Modern Bunker gear can withstand temperatures above
220° F
From a tactical point of view regarding fire behavior what is the most important concept to understand
Flame over or rollover maybe your last warning sign before flash over
Use the gas monitor to ensure CO levels are below what
35 parts per million
The crew going up to investigate a fire alarm should always have what
2.5 gallon pressurized water extinguisher
What is the only method by which firefighters can expel CO
Ventilation
