FIRE EXTINGUISHER

The first fire extinguisher of which there is no record was patented in England in 1723 by Ambrose Godfrey, a celebrated chemist at that time. It consisted of a cask of fire-extinguishing liquid containing a pewter chamber of gunpowder. This was connected with a system of fuses that were ignited, exploding the gunpowder and scattering the solution. This device was probably used to a limited extent, as Bradley’s Weekly Messenger for November 7, 1729, refers to its efficiency in stopping a fire in London.

internationally there are several accepted classification methods for hand-held fire extinguishers. Each classification is useful in fighting fires with a particular group of fuel.

Classes of fire

• Class A – fires involving solid materials such as wood, paper or textiles.
• Class B – fires involving flammable liquids such as petrol, diesel or oils.
• Class C – fires involving gases.
• Class D – fires involving metals.
• Class k –  fires are those that are fueled by flammable liquids unique to cooking, such as cooking oils and greases that are vegetable and animal fat-based.

Fire extinguishers are usually fitted in buildings at an easily accessible location, such as against a wall in a high-traffic area. They are also often fitted to motor vehicles, watercraft, and aircraft – this is required by law in many jurisdictions, for identified classes of vehicles. Under NFPA 10 all commercial vehicles must carry at least one fire extinguisher, with size/UL rating depending on the type of vehicle and cargo (i.e., fuel tankers usually must have a 20 lb (9.1 kg), while most others can carry a 5 lb (2.3 kg)). The revised NFPA 10 created criteria on the placement of “fast flow extinguishers” in locations such as those storing and transporting pressurized flammable liquids and pressurized flammable gas or areas with the possibility of three-dimensional class B hazards are required to have “fast flow extinguishers” as required by NFPA 5.5.1.1. Varying classes of competition vehicles require fire extinguishing systems, the simplest requirements being a 1A:10BC hand-held portable extinguisher mounted to the interior of the vehicle.