Identify the types of fire extinguishers
Class A – fires which involve solid materials such as wood, paper, cardboard, textiles, furniture and plastics where there are normally glowing embers during combustion.
Such fires are extinguished by cooling which is achieved using water
Class B – fires which involve liquids or liquefied solids such as paints, oils or fats. These can be further subdivided into:
Class B1 – fires which involve liquids that are soluble in water such as methanol.
They can be extinguished by carbon dioxide, dry powder, water spray, and light water and vaporizing liquids Class B2 – fires which involve liquids not soluble in water, such as petrol and oil.
They can be extinguished by using foam, carbon dioxide, dry powder, light water and vaporizing liquid
Class C – fires which involve gases such as natural Methods of extinction gas or liquefied gases such as butane or propane.
They can be extinguished using foam or dry powder in conjunction with water to cool any containers involved or nearby.
Class D – fires which involve metals such as aluminium or magnesium.
Special dry powder extinguishers are required to extinguish these fires, which may contain powdered graphite or talc
Class F – fires which involve high temperature cooking oils or fats in large catering establishments or restaurants There are designated extinguishers for such fires
Electrical fires – fires involving electrical equipment or circuitry do not constitute a fire class on their own, as electricity is a source of ignition that will feed a fire until switched off or isolated. But there are some pieces of equipment that can store, within capacitors, lethal voltages even when isolated.
Extinguishers specifically designed for electrical use like carbon dioxide or dry powder should always be used for this type of fire hazard.
Fire extinguishers are usually designed to tackle one or more class of fire.
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