Which extinguisher is most suitable for small electrical equipment fires where water would damage equipment?

• A. Water-based extinguisher
• B. Foam extinguisher
• C. CO2 or dry chemical ABC/BC extinguisher
• D. Wet chemical extinguisher

Answer: (C)

When dealing with a small fire in electrical equipment, the priority is to suppress the fire without introducing water that could conduct electricity or damage sensitive electronics. Water-based agents are out because they can create a shock risk and worsen damage to electrical gear.

Non-water extinguishing options that are safe for energized electrical fires are ideal. CO2 extinguishers fit this need well: they blanket the fire by displacing the surrounding oxygen and do not leave a conductive residue, making them suitable for small electrical fires in equipment. If CO2 isn’t available, a dry chemical extinguisher rated for electrical fires (class C in some classifications) can also be used. The powder is non-conductive and can interrupt the chemical reactions sustaining the flame, making it effective on electrical fires.

Wet chemical extinguishers are designed for cooking fats/oils and involve a reactive liquid that isn’t appropriate for electrical equipment. Foam and water-based extinguishers should be avoided for electrical fires because they introduce water into the scene, which can conduct electricity and damage equipment.

So, the best fit for small electrical equipment fires where water would be harmful is a CO2 extinguisher or a dry chemical extinguisher appropriate for electrical fires.