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History Of The Fire Extinguisher

A fire extinguisher is an active fire protection device used to extinguish or control small fires, often in emergency situations. It is not intended for use on an out-of-control fire, such as one which is rapidly developing, endangers the user (i.e. no escape route, smoke, explosion hazard, etc.), or otherwise requires the expertise of a fire brigade. Typically, a fire extinguisher consists of a hand-held cylindrical pressure vessel containing an agent which can be discharged to extinguish a fire.

There are two main types of fire extinguishers: stored pressure and cartridge-operated. In stored pressure units, the expellant is stored in the same chamber as the firefighting agent itself. Depending on the agent used, different propellants are used. With dry powder extinguishers, nitrogen is typically used; water and foam extinguishers typically use air, however a Service Technician carries nitrogen bottles in their mobile workshops these are normally filled with nitrogen too.

Stored pressure Fire Extinguishers are the most common type. Cartridge-operated extinguishers contain the expellant gas in a separate cartridge that is punctured prior to discharge, exposing the propellant to the extinguishing agent. This type is not as common, used primarily in areas such as industrial facilities, where they receive higher-than-average use. They have the advantage of simple and prompt recharge, allowing an operator to discharge the extinguisher, recharge it, and return to the fire in a reasonable amount of time. Unlike stored pressure types, these extinguishers utilize compressed carbon dioxide instead of nitrogen, although nitrogen cartridges are used on low temperature (-60 rated) models. Cartridge operated extinguishers are available in Dry Powder, Water & Foam


A 1905 illustration marketing extinguishers

A 1905 illustration marketing extinguishers

The first fire extinguisher of which there is any record was patented in England in 1723 by Ambrose Godfrey, a celebrated chemist. It consisted of a cask of fire-extinguishing liquid containing a pewter chamber of gunpowder. This was connected with a system of fuses which 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.

The modern fire extinguisher was invented by British Captain George William Manby in 1818; it consisted of a copper vessel of 3 gallons (13.6 litres) of pearl ash (potassium carbonate) solution contained within compressed air. The soda-acid extinguisher was first patented in 1866 by Francois Carlier of France, which mixed a solution of water and sodium bicarbonate with tartaric acid, producing the propellant CO2 gas.

A soda-acid extinguisher was patented in the U.S. in 1881 by Almon M. Granger. His extinguisher used the reaction between sodium bicarbonate solution and sulphuric acid to expel pressurized water onto a fire. A vial was suspended in the cylinder containing concentrated sulphuric acid.

Depending on the type of extinguisher, the vial of acid could be broken in one of two ways. One used a plunger to break the acid vial, whilst the second released a lead stopple that held the vial closed. Once the acid was mixed with the bicarbonate solution, carbon dioxide gas was expelled and thereby pressurize the water. The pressurized water was forced from the canister through a nozzle or short length of hose.

A classic copper building type soda-acid extinguisher

A classic copper building type soda-acid extinguisher

The cartridge-operated extinguisher was invented by Read & Campbell of England in 1881, which used water or water-based solutions. They later invented a carbon tetrachloride model called the "Petrolex" which was marketed toward automotive use. The chemical foam extinguisher was invented around 1905 by Alexander Laurant of Russia, who first used it to extinguish a pan of burning naphtha. It works and looks similar to the soda-acid type, but the inner parts are different. The main tank contains a solution of water, foam compound (usually made from licorice root) and sodium bicarbonate. A cylindrical metal or plastic chamber holds about a quart and a half of 13% aluminum sulphate and is capped with a lead cap. When the unit is turned over, the chemicals mix, producing CO2 gas. The licorice causes some of the CO2 bubbles to become trapped in the liquid and is discharged on the fire as a thick whitish-brown foam.

In 1910, The Pyrene Manufacturing Company of Delaware filed a patent for a using carbon tetrachloride (CTC) to extinguish fires. The CTC vaporized and extinguished the flames by creating a dense, oxygen-excluding blanket of fumes, and to a lesser extent, inhibiting the chemical reaction. In 1911, they patented a small, portable extinguisher that used the chemical. This consisted of a brass or chrome container with an integrated hand pump, which was used to expel a jet of liquid towards the fire. It was usually of 1 imperial quart (1.1 L) or 1 imperial pint (0.6 L) capacity but was also available in up to 2 imperial gallon (9 L) size. As the container was unpressurized, it could be refilled after use through a filling plug with a fresh supply of CTC.

A chemical foam extinguisher with contents.

A chemical foam extinguisher with contents

A further variety of extinguisher - the Fire grenade - consisted of a glass bottle filled with the liquid that was intended to be hurled at the base of a fire. Early ones used salt-water, but later they were filled with CTC. Carbon tetrachloride was suitable for liquid and electrical fires, and was popular in motor vehicles until the late 1950's, when it was withdrawn because of its toxicity. Exposure to high concentrations damages the nervous system and internal organs. Additionally, when used on a fire, the heat converts CTC to Phosgene, formerly used as a chemical weapon.

In the 1940s, Germany invented the liquid chlorobromomethane (CBM) for use in aircraft. It was more effective and slightly less toxic than carbon tetrachloride and was used until 1969. Methyl bromide was discovered as an extinguishing agent in the 1920s and was used extensively in Europe. It is a low-pressure gas that works by inhibiting the chain reaction of the fire and is the most toxic of the vaporizing liquids, used until the 1960s. The vapour and combustion by-products of all vaporizing liquids were highly toxic, and could cause death in confined spaces.

A glass "grenade" style extinguisher, to be thrown into a fire.

A Pyrene, brass, carbon-tetrachloride extinguisher

A Pyrene, brass, carbon-tetrachloride extinguisher

The carbon dioxide (CO2) extinguisher was invented (at least in the US) by the Walter Kidde Company in 1924 in response to Bell Telephone's request for an electrically non-conductive chemical for extinguishing the previously difficult to extinguish fires in telephone switchboards. It consisted of a tall metal cylinder containing 7.5 lbs. of CO2 with a wheel valve and a woven brass, cotton covered hose, with a composite funnel-like horn as a nozzle. CO2 is still popular today as it is an ozone-friendly clean agent and is useful for an extinguishing a person who is on fire, hence its widespread use in film and television.

An early dry chemical extinguisher, the first ones had copper cylinders, this one is steel.

In 1928, DuGas (later bought by ANSUL) came out with a cartridge-operated dry chemical extinguisher, which used sodium bicarbonate specially treated with chemicals to render it free-flowing and moisture-resistant. It consisted of a copper cylinder with an internal CO2cartridge. The operator turned a wheel valve on top to puncture the cartridge and squeezed a lever on the valve at the end of the hose to discharge the chemical. This was the first agent available for large scale three-dimensional liquid and pressurized gas fires, and was but remained largely a specialty type until the 1950s, when small dry chemical units were marketed for home use. ABC dry chemical came over from Europe in the 1950s, with Super-K being invented in the early 60s and Purple-K being developed by the US Navy in the late 1960s.

A glass "grenade" style extinguisher, to be thrown into a fire.

A glass grenade style extinguisher, to be thrown into a fire

In the 1970's, Halon 1211 came over to the US from Europe, where it had been used since the late 40s or early 50s. Halon 1301 had been developed by DuPont and the US Army in 1954. Both 1211 and 1301 work by inhibiting the chain reaction of the fire, and in the case of Halon 1211, cooling class A fuels as well. Halon is still in use today, but is falling out of favour for many uses due to its environmental impact. Europe and Australia have severely restricted its use, but it is still widely available in North America, the Middle East, and Asia.

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