Class C fires involve which of the following?

• A. Ordinary combustibles
• B. Flammable liquids
• C. Energized electrical equipment
• D. Metals

Answer: (C)

Class C fires involve energized electrical equipment. This means the flame is in devices that are powered or may still carry current, such as motors, switchgear, transformers, or wiring. The defining hazard is electricity, so the extinguishing method must be non-conductive and safe for electronics. Clean agent systems are well suited here because the agents are non-conductive, leave no damaging residue, and extinguish by absorbing heat and interrupting flame reactions, rather than displacing oxygen or conducting electricity. If the electrical supply is cut and the fire is in ordinary combustible materials, flammable liquids, or metals, the classification would shift to the appropriate class, but while equipment remains energized, the situation is Class C.