What is the primary function of a Class D fire extinguisher?

The primary function of a Class D fire extinguisher is to extinguish fires involving combustible metals. These fires can occur when metals such as magnesium, titanium, sodium, and potassium ignite, leading to unique challenges in firefighting due to the intense heat and reactivity of these metals when exposed to water or certain chemicals. Class D extinguishers are specifically designed with agents that can safely smother or cool these types of fires without causing additional hazards.

Class D extinguishers contain dry powder agents that are effective for the specific reactions of combustible metals, helping to prevent the fire from spreading and allowing for effective removal of the burning material. Understanding the properties of combustible metals and the limitations of other fire extinguishers is crucial, as typical extinguishing methods, like water or foam, may exacerbate the situation instead of mitigating it.