Which type of extinguishing agent is used for Class D fires?

Class D fires involve combustible metals, such as magnesium, titanium, and sodium, which react violently with water and most other fire extinguishing agents. Therefore, a specialized extinguishing agent is required to effectively put out these types of fires without exacerbating the situation.

Dry powder is specifically designed to combat Class D fires. This type of agent smothers the fire and cools the burning metal through a chemical reaction that absorbs heat. It is formulated to interrupt the combustion process of metals in a safe manner, providing effective suppression without the risk of re-ignition, which is a significant concern with other extinguishing agents.

In contrast, foam, water, and CO2 are not appropriate for Class D fires. Water presents a substantial risk because it can cause explosions or flare-ups when it comes into contact with burning metals. Foam is similarly ineffective and can worsen the situation. CO2 is designed for Class B and certain Class A fires but is unsuitable for Class D as it lacks the necessary properties to handle combustible metals safely.

Thus, the correct choice of dry powder directly addresses the unique challenges posed by Class D fires, making it the essential extinguishing agent for such scenarios.