Fire Safety Science Digital Archive

The fighting of fires in, or near, electrical equipment carries the risk of electrical shock to the personnel operating the fire-fighting eqiupment. A shock may be caused either by accidental contact with live conductors, or by the extinguishing agent conducting a current which subsequently passes to earth through the body of the operator. The second hazard is made greater as higher voltages come into use for electrical transmission and distribution, as for example, in the supergrid which transmits power at 275 KV. This note is concerned with the hazard associated with the conductivity of the extinguishing agent, and is intended to collate and review the information on this subject which is available at the present time. In the main, the work which has been carried out has been concerned with hose streams of the type likely to be used on large fires, and therefore the most likely to come into contact with electrical installations at high voltages. Some work has been done using hand extinguishers, and these investigations are discussed.