Fire Extinguishers

Fire extinguishers are employed to cover the risk of a small fire, and should be at hand to aid escape in an emergency or to stop a small fire from growing into an unmanageable, larger fire. They are not designed for use on larger fires, such as one which has progressed and needs the fire brigade. Check your company policy as it may be that you’re advised to call the fire brigade before using a fire extinguisher.

The current British Standard BS EN3 requires UK fire extinguishers to be coloured red with a band of colour to illustrate its contents. These are; Red for water, Cream for foam, black for Co2, Blue for powder extinguishers and yellow for wet chemical fire extinguishers.
These different types of fire extinguishers are used to fight different types of fire: Class A fires contain flammable solids such as wood and straw. Class B fires comprise of flammable or combustible liquids such as oil and petrol. Class C fires involve flammable gases such as butane and propane. Class D fires concern flammable metals which include titanium, sodium or magnesium. Finally, class F fires are cooking fat and oil, typically deep fat fryers.

The fire extinguishing power or fire rating of fire extinguishers capable of fighting class A, B and F fires is illustrated using numbers and letters such as 13A, 55B, or 75F. The number refers to the size of fire it can extinguish under test conditions; the letter indicates the fire classification.

To begin and continue, a fire requires 4 elements: heat, fuel, and oxygen, and the chemical reaction between the components. The fire is extinguished by removing any one component. Without sufficient heat, a fire cannot start or go on. Water, Foam and Carbon dioxide extinguishers can reduce the amount of heat. Without fuel a fire will stop as it has nothing to burn. Without enough oxygen, a fire cannot start or carry on. A co2 extinguisher works by depleting the oxygen supply to the fire. The chemical reaction of the three other components is required to start and continue a fire. ABC powder fire extinguishers work by disrupting the chemical reaction.

The regulatory reform (fire safety) order requires most public buildings and workplaces to have fire extinguishers in place for emergency use. In the UK there is no legislation to have fire extinguishers in a private dwelling but it would be advisable to have a multi-purpose fire extinguisher available in your home.