NFST NFST Fire Behavior and Science 2

Question 1

Which extinguishing agent is most effective on a Class A fire involving ordinary combustibles like wood and paper?

Accepted Answer

Water

Answer

Dry chemical

Answer

CO2

Answer

Halon

Question 2

What term describes the lowest temperature at which a liquid fuel produces enough vapor to ignite?

Accepted Answer

Flash point

Answer

Boiling point

Answer

Auto-ignition temperature

Answer

Combustion threshold

Question 3

Smoke rising quickly and freely from a building generally indicates what about the fire conditions inside?

Accepted Answer

There is adequate ventilation and the fire is oxygen-rich

Answer

The fire is fully developed

Answer

A backdraft is imminent

Answer

The fire has self-extinguished

Question 4

What is the primary purpose of ventilation during a structure fire?

Accepted Answer

To remove heat, smoke, and gases to improve visibility and reduce fire spread

Answer

To increase oxygen supply for firefighters

Answer

To cool the building structure

Answer

To create a backdraft to extinguish the fire

Question 5

Which phase of fire development is characterized by limited fuel and plentiful oxygen?

Accepted Answer

Incipient (growth) phase

Answer

Fully developed phase

Answer

Decay phase

Answer

Flashover

Question 6

What phenomenon occurs when burning liquid fuel floats on water and spreads, potentially worsening a flammable liquid fire?

Accepted Answer

Boilover

Answer

Slop-over

Answer

Froth-over

Answer

Surge-over