Which extinguisher is effective on fires involving powdered metals?

Sodium Chloride extinguishers, often referred to as Class D extinguishers, are specifically designed for fires involving combustible metals, including powdered metals. This type of extinguisher works by smothering the fire and forming a crust over the burning material, which prevents oxygen from reaching it and thereby extinguishing the flames.

Combustible metals can pose unique challenges in firefighting due to their capacity to burn at very high temperatures and react violently with water or other extinguishing agents. Sodium Chloride effectively combats these types of fires because it is chemically inert and creates a barrier that is effective in cutting off the oxygen supply.

Other choices may not be suitable for handling powdered metal fires. For example, lithium alloy and potassium chloride extinguishers are effective for specific types of fires, but they may not provide the same level of safety or effectiveness when it comes to the unique properties of powdered metals. Potassium phosphate is generally used for multi-class fire situations, primarily Class A and B, making it less suitable for the specific requirements of Class D fires involving metals.