Which statement is true about water-based extinguishers?

• A. They are safe for energized electrical equipment
• B. They are generally appropriate for Class A fires
• C. They are designed for Class D fires
• D. They are specifically designed for Class K fires

Answer: (B)

Water-based extinguishers work by cooling the fuel, absorbing heat and bringing the material down below its ignition temperature. That cooling effect makes them most effective on ordinary combustibles like wood, paper, fabric, and other Class A materials. Because of this cooling action, they are generally appropriate for Class A fires, which is why this statement is true. They’re not the right tool for metal fires (Class D) or cooking oil fires (Class K), which need specialized agents, and they aren’t suitable for energized electrical fires unless the equipment is de-energized or the extinguisher is specifically rated for electrical use.