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Information About

Fire Extinguisher




A fire extinguisher is an Active Fire Protection device used to extinguish or control small fires, often in emergency situations. Typically, a fire extinguisher consists of a handheld cylindrical Pressure Vessel containing an Agent which can be discharged to extinguish a Fire .


USAGE


The typical steps for operating a stored pressure fire extinguisher (described by the acronym "PASS") are the following:

: P - Pull the safety pin
  • about 4-10 feet away)

  • : S - Squeeze the handle

: S - Sweep the extinguisher from side to side while aiming at the base of the fire

  • The approximate starting distance varies by the size and type of the extinguisher. (ie. Water APW vs. 2 1/2 lb. Dry Chemcial.)

  • ---If using a cartridge operated extinguisher you must push down on the cartridge puncturing lever to pressurize the extinguisher after pulling the pin.

  • ---CO2 fire extinguishers usually have a horn-shaped nozzle. Do not touch this horn (or the pipe linking it to the extinguisher) when attempting to put out a fire - your hand may freeze to the extinguisher.


There are various types of extinguishers, which are used for different types of fires; using the wrong type can worsen the fire hazard, but using the right one can better the situation.


HISTORY


The modern fire extinguisher was invented by British Captain George William Manby in 1818; it consisted of a copper vessel of 3 Gallon s (13.6 Litre s) of pearl ash ( Potassium Carbonate ) solution contained within Compressed Air .

The soda-acid extinguisher was invented in the 19th century, which contained a cylinder of 1 or 2 gallons of water with Sodium Bicarbonate mixed into it. 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, while the second released a lead bung 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.

Around 1912 Pyrene invented the Carbon Tetrachloride or CTC extinguisher, which expelled the liquid from a Brass or Chrome container by a handpump; 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. The CTC vaporized and extinguished the flames by chemical reaction. The extinguisher was suitable for liquid and electrical fires, and was popular in motor vehicles for the next 60 years. The vapor and combustion by-products were highly toxic, and could cause death in confined spaces.


CLASSIFICATION

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.


Australia