What is the appropriate extinguishing medium for a Class "D" fire?

The appropriate extinguishing medium for a Class "D" fire is dry powder. Class "D" fires involve combustible metals such as magnesium, titanium, sodium, and potassium. These types of fires require special handling and extinguishing methods because water or standard fire extinguishing agents can react violently with the burning metals.

Using dry powder agents is effective for Class "D" fires because these powders are specifically formulated to smother the flames and may also create a barrier between the burning metal and the oxygen in the atmosphere. The powders work by absorbing heat and suppressing the fire without causing explosive reactions that could occur with other extinguishing mediums.

In contrast, carbon dioxide, aqueous film forming foam, and dry chemical agents are not suitable choices for Class "D" fires. Carbon dioxide may not effectively smother a metal fire, while aqueous film forming foam can react negatively with metal fires, and traditional dry chemical extinguishers are typically designed for Class A, B, or C fires rather than Class D. Thus, dry powder is the only appropriate extinguishing medium for effectively combating a Class "D" fire.