There are five types and all are colour coded. All extinguishers are required to be red with the appropriate colour band to denote its contents.
The most common extinguisher, all red, is the Class A extinguisher. It’s the most widely used and the cheapest. It is used to fight fires involving paper, cardboard, wood and most plastics. These extinguishers contain water and are not to be used on electrical fires.
Foam fire extinguishers with a colour band of cream can be used on flammable liquid fires caused by petrol/gasoline and oil. These are known as Class B extinguishers and can also be used on fires fought with a Class A extinguisher. Foam extinguishers are not recommended for fighting electrical fires although they are safer than water based extinguishers.
Dry powder fire extinguishers with a colour band of blue are sometimes referred to as the multi-purpose extinguisher because they can be used to fight Class A, B and C fires. Class C fires are those involving gases such as butane, methane and propane.
Class D fires are those involving metals and for which a special dry powder is used.
CO2 fire extinguishers with a colour band of black contain carbon dioxide and are used to fight fires involving electrical appliances. These are known as Class E fires