Kinds of fire extinguishers

As you know, a fire extinguisher is the most important and most effective means of fighting a fire. With the help of it for several minutes you can stop the fire. Therefore, in each organization in a prominent and accessible place should be located this primary means of fire safety. Types of fire extinguishers depend on the substances contained in them. They can be in the form of water, foam, powder, carbon dioxide, nitrogen and other chemical inert gases. When the fire extinguisher is put into operation, a substance is released from its nozzle, which also extinguishes the fire. The release of the contents takes place under very high pressure.

Types of fire extinguishers used in fires depend on the nature of the fire. There are four common fire classes that have been assigned the appropriate symbols. The first class (A) is the combustion of solid substances, which is accompanied by decay. These include wood, paper, textiles. Class B includes the combustion of liquid substances that do not dissolve in water (gasoline, petroleum products, ether), as well as soluble elements (alcohol, glycerin). Class C includes the ignition of gaseous substances (household gas, propane). Class D fire - combustion of metals and their alloys (metal hydrides, organometallic compounds). To class E is the ignition of electrical equipment.

When igniting liquid, solid and gaseous substances, such types of fire extinguishers as powder ones are used. The jet of powder must be moved in different directions in order to bring down the flame.

After this has been done, it is necessary to completely cover the individual foci of ignition with a layer of powder. During these actions, it must be given in intermittent portions. When burning liquid substances (fire class B), the jet should be sent primarily to the near edge. The powder must be fed continuously. In this case, the valve must be fully open. Moving should be so that the back and sides do not have outstanding areas, and in the combustion zone, a powder cloud must be constantly maintained.

When igniting gaseous substances, the jet of powder should be directed almost parallel to the gas stream, directly into the gas stream. When extinguishing the electrical equipment (of course, de-energized), the stream of powder should be directed directly to the source of the flame. The expiration date of the fire extinguisher (on average) is ten years.

Carbon dioxide fire extinguishers are used to extinguish fires belonging to class B (ignition of liquid substances), as well as to class E (electrical equipment). Liquefied carbon dioxide is their main active agent. They are manual, mobile, stationary. Manual extinguishers extinguish the ignition of electrical installations with a voltage of up to 1000V. Mobile are used to extinguish flammable liquids located on an area of up to five square meters, as well as a small size of electrical installations that are under tension. They are also used in the case when it is undesirable, for example, the use of water (in art galleries, museums or archives). The life of carbon dioxide fire extinguishers is up to ten years.

Foam extinguishers are used almost everywhere. They use chemical foam, obtained from solutions of alkalis and acids, as well as air-mechanical, which is formed from aqueous solutions of foaming agents by air, carbon dioxide or nitrogen.

There are also types of fire extinguishers, such as aerosol. They are used to extinguish flammable liquids, flammable, as well as electrical installations under voltage, of various materials, excluding alkali metals and oxygen-containing substances. They are limited to a shelf life of five years.

There is another type of fire extinguisher - it is a self-converting powder OSB-1. It is used for class A, B, C, E fires. Its main feature is automatic operation without human intervention.

It will not be superfluous for everyone and everyone to recall that if an ignition is detected, it is necessary, as soon as possible, to call the fire engine immediately .