Which extinguisher is suitable for electrical fires (Class C)?

• A. CO2
• B. Water
• C. Dry chemical ABC
• D. Class K

Answer: (C)

Electrical fires require extinguishing agents that won’t conduct electricity and won’t leave a conductive path or damage sensitive equipment. The dry chemical ABC extinguisher fits this need because its powder is non-conductive and it interrupts the chemical reactions occurring in the flame, making it effective on energized electrical equipment as well as ordinary combustibles and some liquids. Water should be avoided on live electrical fires since it conducts electricity and can create shock hazards or spread the heat, potentially damaging more equipment. A Class K extinguisher is designed for cooking oils, not electrical gear, and CO2 extinguishers, while non-conductive, can displace oxygen in occupied or enclosed spaces and may not provide the same residue protection for some electrical components. So the dry chemical ABC extinguisher is the best choice for an energized electrical fire.