Fire extinguisher five categories. In the UK the use of Halon gas is now prohibited except under certain situations such as on aircraft and in the military and police. Fire extinguishing performance per fire class is displayed using numbers and letters such as 13A, 55B. EN3 does not recognise a separate electrical class - however there is an additional feature requiring special testing (35 kV dielectric test per EN 3-7:2004). A powder or CO extinguisher will bear an electrical pictogramme as standard signifying that it can be used on live electrical fires (given the symbol E in the table). If a water-based
Fire extinguisher handpump, which was used to expel a jet of liquid towards the fire. It was usually of or capacity but was also available in up to size. As the container was unpressurized, it could be refilled after use through a filling plug with a fresh supply of CTC. Another type of carbon tetrachloride extinguisher was the fire grenade. This consisted of a glass sphere filled with CTC, that was intended to be hurled at the base of a fire (early ones used salt-water, but CTC was more effective). Carbon tetrachloride was suitable for liquid and electrical fires and the extinguishers