CPS Fire Behavior and Combustion 2

Question 1

What is the fourth element added to expand the fire triangle into the fire tetrahedron?

Accepted Answer

Uninhibited chain reaction

Answer

The fire tetrahedron adds the uninhibited chemical chain reaction as a fourth element, recognizing combustion as a self-sustaining chemical process.

Question 2

What is pyrolysis?

Accepted Answer

The chemical decomposition of a material by heat, producing flammable gases

Answer

Pyrolysis is the thermal decomposition of solid or liquid fuels by heat, releasing flammable vapors that then mix with oxygen and ignite.

Question 3

What is rollover (flameover) in a structure fire?

Accepted Answer

When flames roll across the ceiling through accumulated unburned gases ahead of the main fire

Answer

Rollover occurs when unburned flammable gases accumulate at the ceiling level and ignite, creating flames that roll across the ceiling in advance of the main fire.

Question 4

Which fire class involves fires in flammable and combustible liquids and gases?

Accepted Answer

Class B

Answer

Class B fires involve flammable liquids (gasoline, oil) and flammable gases, which require foam, CO2, or dry chemical agents for suppression.

Question 5

What does the lower flammable limit (LFL) of a gas indicate?

Accepted Answer

The minimum concentration of gas in air required to sustain combustion

Answer

The lower flammable limit is the minimum concentration of a fuel gas mixed with air below which the mixture is too lean to ignite and sustain combustion.

CPS Firefighter Test Practice Test

CPS Firefighter Test Practice Test

CPS Fire Behavior and Combustion 2