Ch. 5 - Fire Behavior Flashcards
(35 cards)
Chemical reaction that gives off heat
exothermic
Chemical reaction that absorbs heat
endothermic
Conditions needed for fire
oxygen-fuel-heat
Pyrolysis
process that liberates flammable vapors from a fuel source
Conduction
process of transferring heat between two solids
Convection
transfer of heat by the flow of gas or liquid from hotter areas to cooler areas
Radiation
transfer of heat through the emission of energy
Class A Fire
ordinary solid combustible materials
Class B Fire
flammable or combustible liquids
Combustible material
a material that can combust when heated
Flammable material
a material that will combust immediately on exposure to heat
Class C Fire
energized electrical equipment
Class D Fire
combustible metals
Class K Fire
cooking oils and fat
HRR
Heat release rate; rate at which heat energy is generated
Thermal layering
process by which hot gases rise to the top
Neutral Plane
boundary between hot and cool gases
Rollover
spontaneous ignition of hot gases in the upper levels of a room; also known as flameover
Flashover
when all exposed surfaces have ignited
What is the critical temperature when flashover can occur?
1000F
Backdraft
occurs when oxygen is introduced to a ventilation-limited fire
Stages of Fire Development
- Incipient Stage
- Growth Stage
- Fully Developed
- Decay Stage
Volitility
amount of liquid that vaporizes
Flammable range
range in concentration between upper and lower flammable limits