Sri Vari Technologies

Fire extinguisheris a fire protectiondevice used to extinguish or control small fires or in emergency situations. Fire extinguisher consists of a hand-held cylindricalpressure vesselcontaining achemical agent which can be discharged to extinguish afire.

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 thefirefightingagent itself. Depending on the agent used, different propellants are used. With dry chemical extinguishers,nitrogenis typically used; water and foam extinguishers typically use air. 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 use compressedcarbon dioxideinstead of nitrogen, although nitrogen cartridges are used on low temperature (-60 rated) models. Cartridge operated extinguishers are available in dry chemical and dry powder types in the U.S. and in water, wetting agent, foam, dry chemical (classes ABC and B.C.), and dry powder (class D) types in the rest of the world.

Fire extinguishers are further divided into handheld and cart-mounted (also called wheeled extinguishers). Handheld extinguishers weigh from 0.5 to 14 kilograms (1.1 to 30.9lb), and are hence, easily portable by hand. Cart-mounted units typically weigh more than 23 kilograms (51lb). These wheeled models are most commonly found atconstruction sites,airportrunways,heliports, as well asdocksandmarinas.