CPS Fire Behavior and Combustion 3

Question 1

What is a BLEVE (Boiling Liquid Expanding Vapor Explosion)?

Accepted Answer

An explosion caused when a container holding pressurized liquid fails while the liquid is at or above its boiling point

Answer

A BLEVE occurs when a pressurized vessel fails catastrophically while containing liquid heated above its atmospheric boiling point, causing a violent explosion and fireball.

Question 2

Which type of heat transfer does NOT require a physical medium and can travel through a vacuum?

Accepted Answer

Radiation

Answer

Radiation transfers heat through electromagnetic waves that require no physical medium, which is why you can feel heat from fire even without touching it or being in its smoke path.

Question 3

What primary warning sign indicates a backdraft may be imminent when approaching a structure?

Accepted Answer

Smoke-stained windows, smoke puffing in and out of openings, and little or no visible flame

Answer

Backdraft warning signs include smoke-stained windows, smoke puffing rhythmically from openings (breathing), and little visible flame indicating an oxygen-starved fire.

Question 4

Which extinguishing method works by removing heat from the combustion process?

Accepted Answer

Cooling

Answer

Cooling removes heat from the fire tetrahedron by absorbing thermal energy, which is why water is so effective — it absorbs large amounts of heat as it converts to steam.

Question 5

What does 'auto-ignition temperature' mean for a fuel?

Accepted Answer

The minimum temperature at which a fuel will spontaneously ignite without an external ignition source

Answer

Auto-ignition temperature is the minimum temperature at which a substance will spontaneously ignite in normal atmosphere without an external spark or flame.

CPS Firefighter Test Practice Test

CPS Firefighter Test Practice Test

CPS Fire Behavior and Combustion 3