The powder extinguishing systems are meant for room and equipment protection.The extinguishing powders used in powder extinguishing systems are highly efficient,quick-acting extinguishants.The sudden extinguishing effect of the powder cloud is caused by the suffocation effect and the anticatalytic effect,a chemical intervention into the combustion process.Extinguishing powders mainly consist of non-poisonous inorganic salts mixed with waterproofing and pouring agents.They are used for fires with solid,liquid or gaseous substances and for metal fires,thus,they are used for fire classification A,B,C and D.