According to the type of combustible and the combustion characteristics, the fire is divided into A, B, C, D, E, F, K seven categories.
The dry chemical powders name according to what types of fire they can be used, such as BC dry powder can extinguish Class B and Class C, ABC dry powder can put out Class A, B and Class C.
Class A fire: refers to solid matter fire. This substance is usually organic and generally produces burning embers when burned.Such as wood, coal, cotton, wool, hemp, paper and other fires.
Class B fire: A fire of a liquid or molten solid substance.Such as kerosene, diesel, crude oil, methanol, ethanol, asphalt, paraffin and other fires.
Class C fire: refers to gas fire.Such as gas, natural gas, methane, ethane, propane, hydrogen and other fires.
Class D fire: refers to metal fire.Such as potassium, sodium, magnesium, aluminum magnesium alloy and other fires.
Class E fire: live fire.A fire in which an object is burned live.
Class F fire: A fire of cooking objects (such as animal and plant oils) in cooking utensils.
Class K fire: edible oil type fire.
Usually the average combustion rate of edible oil is greater than hydrocarbon oil, compared with other types of liquid fires, edible oil fires are difficult to be extinguished, because there are many different behavior skewed from hydrocarbon oil fires, it is divided into a separate category of fire.
There are many types of dry powder fire extinguishing agents, which can be broadly divided into three categories:
1. Dry powder based on sodium bicarbonate (potassium) to extinguish fires in flammable liquids, gases and live equipment; This is BC dry powder chemical
2. Dry powder based on ammonium phosphate, diammonium phosphate, ammonium phosphate and its mixture setomodo, used to extinguish fires of flammable solids, flammable liquids, flammable gases and charged equipment; this is ABC dry powder chemical: ABC dry powder 50%,ABC dry powder 90%,etc.
3. Dry Powders based on sodium chloride, potassium chloride, sodium chloride, sodium carbonate, etc., are used to put out light metal fires. That is BCD dry chemical powder.