What is the primary chemical compound found in a PKP extinguisher?

The primary chemical compound found in a PKP (Purple K Powder) extinguisher is potassium bicarbonate. This compound is highly effective in combating flammable liquid fires (Class B fires) and is appreciated for its ability to disrupt the chemical reaction that fuels the fire. When discharged, potassium bicarbonate forms a layer of powder that smothers the flames, preventing oxygen from reaching the fuel sources.

Unlike other chemical agents, potassium bicarbonate is more efficient in tackling certain types of fires, particularly those involving hydrocarbons. It is important to understand that while other extinguishing agents exist, such as ammonium phosphate which is used in Class A and B applications, potassium bicarbonate is specifically designed for handling the unique challenges posed by flammable liquids.