Powders have been commonly used in the marketplace for a long time. Dry chemical powder is an extremely effective fire-fighting agent that suppresses fire by interfering with the chain reaction of combustion by coating the surface of the burning material. The coating separates the fuel from the oxygen supply. They are tried and tested over a wide range of applications and is the most used agent for handheld extinguishers due to their diversity. Powder does have a draw back as it can leave a mess behind however this is outweighed by its effectiveness at fast knock down and reducing the likelihood of a fire spreading. Powder can be used on electrical and oil fires as it is non-conductive and reduces oxygen in the air as well as on the surface.