Class K rated extinguishers work because of what process that converts fatty acids into a soapy film?

Class K rated extinguishers are specifically designed for fires involving cooking oils and fats, which are commonly found in commercial kitchens. The process that allows these extinguishers to effectively smother and put out these types of fires is known as saponification. During saponification, the high-temperature fats and oils react with certain chemicals in the extinguishing agent, generally a potassium carbonate-based solution, to form a soapy film on the surface of the burning substance.

This soapy film serves multiple purposes: it cools the combustible material, prevents re-ignition, and effectively isolates the fire from the surrounding oxygen. The formation of this film is critical because it disrupts the combustion process, which relies on the presence of fuel, heat, and oxygen. Therefore, the ability of Class K extinguishers to engage in saponification makes them uniquely effective for handling kitchen fires.

In contrast, the other processes listed—combustion, oxidation, and reduction—do not directly pertain to the use of Class K extinguishers or the mechanism by which they suppress fires involving cooking fats. Combustion refers to the chemical reaction that produces fire, oxidation involves reactions that require oxygen but do not involve the creation of the protective film needed for