Structural Flashcards
1
Q
What does B-SAHF stand for?
A
Building
Smoke
Air
Heat
Flame
2
Q
What are the 4 stages of compartment fire?
A
- Developing
- Flashover (transitional)
- Fully Developed
- Decay
3
Q
Define the developing stage of compartment fire?
A
- Fire is small compared to the size of the compartment.
- Fire has adequate oxygen and is not confined by the sized of the compartment.
4
Q
What are the (4) types of heat transfer?
A
- Conduction
- Convection
- Radiaition
- Direct Burning
5
Q
Descibe how conduction contributes to the spead of fire?
A
- The transfer of heat through a solid material, from a region of higher temperature to a region of lower temperature.
- Heat can be conducted from the fire compartment to other compartments.
6
Q
Descibe how convection contributes to the spead of fire?
A
- Convection is heat transfer due to the mass movement of the heated molecules/gases within a liquid or gas.
- Majority of heat movement and spread throughout a structure.
- Hot gaseous products of combustion and pyrolysis mix with air, expand and rise rapidly carrying the hot air away from the seat of the fire.
7
Q
Descibe how radiation contributes to the spead of fire?
A
- Waves carry energy away from the emitting object.
- Aids fire spread across a surface and promotes ignition of other fuels.
8
Q
Descibe how direct burning contributes to the spead of fire?
A
- Direct contact between the flame and the material.
- Flames contact other fuel sources which then also catch fire.
9
Q
Define the flashover stage of compartment fire?
A
- Materials in compartment heat to their autoignition temperature and emit flammable gases.
- Rapid ignition of these gases and all combustible material occurs.
10
Q
Define the fully developed stage of compartment fire?
A
- Flashover has occurred.
- Heat release rate has peaked.
- Everything combustible within the compartment is on fire.
- Average temperature may range from 700 to 1200°C.
11
Q
Define the deacy stage of compartment fire?
A
- All available fuel has been consumed.
- Rate of heat release has declined.