Certified Fire Inspector II Practice Test 2026 - Free Practice Questions and Study Guide for Fire Inspectors

Class C fires involve energized electrical equipment, such as wiring, circuit breakers, and appliances. The appropriate fire extinguisher for these types of fires must not be conductive, as using a water extinguisher or foam extinguisher could create a risk of electric shock.

Carbon dioxide (CO2) extinguishers are suitable for Class C fires because they do not conduct electricity and effectively displace the oxygen around the fire, leading to suffocation of the flames. Additionally, CO2 extinguishers leave no residue, making them ideal for use on electrical equipment where damage from residual agents could be a concern.

In contrast, water extinguishers are ineffective and dangerous for Class C fires, as water can conduct electricity and create a shock hazard. Dry chemical extinguishers can be used on Class C fires, but they are not as effective as CO2 extinguishers in scenarios with sensitive electrical equipment. Foam extinguishers are primarily designed for Class A and B fires and should not be used for electrical fires due to the risk of conductivity.

Therefore, the use of carbon dioxide extinguishers is the safest and most effective approach for tackling Class C fires.