Explanation
Potassium bicarbonate is a dry chemical agent that is considered to be twice as effective as sodium bicarbonate in fire suppression, especially for Class B fires involving flammable liquids and gases. This is because potassium bicarbonate has a higher melting point and a lower decomposition temperature than sodium bicarbonate, which allows it to form a more stable and insulating layer on the burning surface.Potassium bicarbonate also has a lower pH and a higher specific gravity than sodium bicarbonate, which enhances its penetration and dispersion abilities123.References:Dry Chemical Agents - Purple-K Powder is Purple - Chemguard;Evaluation of Dry Chemical Fire Extinguishing Standards - NFPA;Potassium bicarbonate - Wikipedia.