Why should water-based extinguishers not be used on electrical fires?

• A. They are heavy
• B. Water conducts electricity and can pose a shock hazard to the operator and equipment
• C. They leave a sticky film
• D. They are always ineffective on electrical fires

Answer: (B)

Water conducts electricity, so using a water-based extinguisher on an electrical fire can create a path for current to flow from the live equipment to you. That means you could be shocked, and the current could energize the extinguisher or other metal around the scene, potentially spreading the hazard. Because of this, the safe approach is to de-energize the equipment if it can be done safely, and to use non-conductive extinguishing agents such as carbon dioxide or dry chemical powders that do not carry electricity and won’t create a conductive path. The other reasons listed are not the core safety issue here; the key point is the electrical conductivity of water and the shock risk it creates.