NFST NFST Fire Behavior and Science

Question 1

What is the minimum oxygen concentration required to sustain flaming combustion?

Accepted Answer

16%

Answer

Flaming combustion generally requires at least 16% oxygen concentration to sustain itself.

Question 2

Which of the following best describes 'flashover' in a structure fire?

Accepted Answer

When all combustible surfaces in a room ignite nearly simultaneously

Answer

Flashover occurs when all combustible surfaces in a compartment reach ignition temperature and burst into flame almost simultaneously.

Question 3

The three components of the fire triangle are fuel, heat, and which third element?

Accepted Answer

Oxygen

Answer

The fire triangle consists of fuel, heat, and oxygen — remove any one and the fire will extinguish.

Question 4

What type of heat transfer occurs when heat moves through direct contact between objects?

Accepted Answer

Conduction

Answer

Conduction is heat transfer through direct physical contact between materials.

Question 5

Which class of fire involves energized electrical equipment?

Accepted Answer

Class C

Answer

Class C fires involve energized electrical equipment and require non-conductive extinguishing agents.

NFST Test Practice Test