Clean agent systems shall not be used on which hazards?

• A. Reactive chemicals and metal hydrides
• B. Ordinary combustibles
• C. Electrical fires
• D. Plastic fires

Answer: (A)

Clean agent suppression is designed to control fires by interrupting the flame chemistry or by displacing the air, often in enclosed spaces. But certain fuels are not compatible with these agents. Reactive chemicals and metal hydrides can react with halogenated or other clean agents, potentially producing dangerous byproducts, releasing hydrogen, or causing a violent or rekindling reaction. Because of these potential hazards, clean agent systems shall not be used on fires involving reactive chemicals or metal hydrides. In contrast, many clean agent systems are suitable for electrical fires or ordinary combustibles, as long as the specific agent and circumstances are appropriate.