F04 Portable Fire Extinguishers 2

Question 1

What is the primary advantage of a CO2 fire extinguisher over a dry chemical extinguisher when used on energized electrical equipment?

Accepted Answer

CO2 leaves no residue that could damage sensitive equipment

Answer

CO2 discharges as a gas and leaves no residue, making it ideal for energized electrical equipment and sensitive electronics.

Question 2

A wet chemical (Class K) fire extinguisher is specifically designed for use in:

Accepted Answer

Commercial cooking operations with vegetable or animal oils

Answer

Wet chemical extinguishers create a soapy foam that cools cooking oils and seals the surface, preventing re-ignition — making them essential for commercial kitchens.

Question 3

Which type of portable fire extinguisher is most appropriate for a Class D (combustible metal) fire?

Accepted Answer

Specialized dry powder agent designed for the specific metal

Answer

Class D fires involving combustible metals like magnesium or sodium require specialized dry powder agents; water and CO2 can intensify these fires.

Question 4

An extinguisher labeled '2-A:10-B:C' — what does the '2-A' rating indicate?

Accepted Answer

It is equivalent to approximately 2.5 gallons of water on Class A fires

Answer

The numerical prefix in a Class A rating represents water firefighting equivalency — each unit equals approximately 1.25 gallons of water.

Question 5

Which extinguishing agent should NEVER be used on a fire involving a commercial deep fryer with cooking oil?

Accepted Answer

Water

Answer

Water causes a violent steam explosion when applied to hot cooking oil, dramatically spreading the fire and creating a dangerous fireball.

(F04) F04 Fireguard License Practice Test

(F04) F04 Fireguard License Practice Test

F04 Portable Fire Extinguishers 2