How To Extinguish a Fire
Is fire truly a living thing? It consumes fuel and oxygen, produces heat and waste, it grows and moves. Weather fire is alive or not, it is still dangerous, so you should always treat it with care. There are four main types of fires which are rated in class A, B, C and D. Knowing how to put particular fires out could save your property, someone’s life, or your own life.
In order to know how to put fires out, you must first know how one starts. For a fire to occur, there must be three things present: Fuel, oxygen, and heat. Fuel is any combustible material, weather it be solid, liquid, or gas. Most solid and liquid fuels become a vapor or gas before they will ignite. Making fuel a vapor requires heat, which is the amount of energy necessary to raise the temperature of the fuel so that enough vapors are given off for ignition. The final ingredient for fire is oxygen. The atmosphere required for fire must be at least 16% oxygen, the air we breathe is about 21%. When these three ingredients combine, you get a chemical reaction known as fire.
The most common type of fire is the class A fire. In this type of fire, the fuel is usually ordinary combustibles or fibrous materials. Examples of these are wood, paper, cloth and plastic. These fires must be extinguished by cooling the material below it’s ignition temperature and soaking the fibers to keep them from lighting again. Use ABC rated fire extinguishers, foam, or water.
Another common type of fire is the type B fire. These fires are fueled by flammable or combustible liquids. These liquids are substances like kerosene, gasoline and paint thinner. Class B fires must be extinguished by removing the oxygen or preventing the vapors from reaching the source of the ignition. Use B,C rated dry extinguishers, foam, carbon dioxide, and halon extinguishers.
The final common type of fire is the class C fire. These fires are dangerous because the object that is ablaze is electrically charged. This type of fire is found anywhere from panel boxes and outlets to blenders and irons. Always use an extinguishing substance that will not conduct electricity. Some types of non-conductive extinguishers include carbon dioxide, BC rated dry chemical and halon. DO NOT water on electrical equipment.
The last type of fire is very uncommon for most people. It is a class D fire, which is fueled by certain combustible metals such as potassium, sodium, titanium and magnesium. These metals are very dangerous because they burn at extremely high temperatures in order to give off enough oxygen for combustion. In order to put out class D fires, you must use the dry powder extinguisher that is specified for the material involved. Do not use water or chemicals that aren’t specified for the material, they may react violently with the metal.
All four of these fire types are dangerous, but with proper safety measures, they can be prevented.