Classes/Types of Fire and how to Extinguish

Hi, in this video we are going to explain the classes or types of fire and how to extinguish each type of fire. First we explain the definition of fire. So what is fire? Fire is a result of a chemical reaction known as combustion in which energy is produced in the form of visible heat. For a fire to occur three basic elements must be present in proper proportion. These elements are fuel, heat and oxygen combinedly known as the fire triangle. The fire will go out if we take away any element of the triangle. Fire can be classified in five different types depending on the source of fire. Knowing how to extinguish certain type of fire comes handy in case of emergencies. If we don't know about the nature and type of fire or efforts to extinguish the fire may result in further trouble because of improper method used for extinguishing the fire. For example using water on electrical fire can actually make it more dangerous rather than extinguishing it. Different types of fire are differentiated from each other based on their intensity, temperature and visibility. Fires can be classified in five different classes that is class A, B, C, D and K. Now we explain each type of fire along with the fire extinguishers used for each type. Class A fires are the most common type of fire and are caused by ordinary combustible materials like wood, cloth, paper, plastic etc. Class A fires are the easiest type to extinguish. These fires are extinguished by taking out the heat element of the fire triangle. Mostly water is used to extinguish class A fires. In extreme cases foam, sand or halon gas can also be used. Class A extinguishers are identified by a triangle symbol in green color with a capital letter A. Now we explain class B fires. Class B fires are fueled by flammable liquids or gases such as alcohol, gasoline, petroleum oil or oil-based paints etc. This classification does not include fires caused by cooking oils. Water cannot be used to extinguish class B fires as the water might cause spreading the flaming material rather than extinguishing it. These types of fire can be deadly and can spread quickly on large areas in a short time. These fires are extinguished by cutting off the oxygen element of the fire triangle. These types of fires are extinguished by the use of dry chemical powder, foam, CO2 extinguishers. Class B extinguishers are represented by square symbol with red color and capital letter B. Next we explain class C fires. These fires are caused by energized electrical equipment. These fires can result due to old wiring with weak insulation or due to faulty appliances. These fires are very common. First step in case of electrical fire is to isolate the faulty portion from the rest of the system. Never use water, foam or any solution containing water on electrical fires as these materials can conduct electricity and can result in serious trouble. The best extinguisher in case of electrical fires are dry chemical powder, CO2 or halon gas. Class C fires are extinguished by taking away the heat element of the fire triangle. These fire extinguishers are denoted by a circle symbol with blue color and capital letter C. Another type of fires are class D fires. Class D fires are caused by combustible metals like titanium, sodium and magnesium. It takes very high levels of heat to melt and ignite these metals. That's why these types of fires are rare and expected only at laboratories and industries etc. The best way to extinguish these fires are by eliminating the oxygen element of fire. These fires are generally extinguished with the use of DCP. However, sand can also be used to extinguish small quantity of fire. Class D extinguishers are denoted by a star symbol with yellow color and capital letter D. Another important type of fires are class K fires. Class K fires generally occur in cooking appliances that use cooking media like vegetable oils, fats, animal oils etc. These types of fires commonly occur at homes or restaurants. These fires are extinguished by cutting the heat element of the fire triangle. Wet chemical powder is used to extinguish such fires. These extinguishers are identified by the symbol capital letter K. Thanks for watching the video and subscribe the channel for more such informative videos.