Nine kilogram Chubb fire extinguisher, type PSK9, 1979.
© Science Museum / Science & Society Picture Library
Partly sectioned example. Made by Chubb Fire Security Ltd, this stored presure powder type extinguisher can be used on all clas A, B and C fires. Different types of extinguisher are available for different kinds of fire. Clas A fires (solid combustibles such as paper, wood, textiles and furnishings) can be extinguished with water or carbon dioxide. Clas B fires (flammable liquids such as oil and petrol) are extinguished with carbon dioxide, chemical foam, dry powder, or halogenated hydrocarbons. And clas C fires (electrical equipment) require nonconducting extinguishers, such as carbon dioxide, dry chemicals, or halogenated hydrocarbons.