A fire extinguisher is one of the primary means of extinguishing, thanks to which a sudden fire can be quickly eliminated without allowing a large fire to grow. Therefore, the presence of a fire extinguishing device is a mandatory fire safety measure for industrial enterprises, office buildings, cars and residential buildings. It is important to know what fire extinguishers are and how to use them in an emergency.
Classification and rules of use
A fire extinguisher is a cylinder in which a fire extinguishing compound is held under high pressure, designed for rapid fire localization. When the trigger is activated, the content flows out through the siphon tube and bell.
A fire extinguisher is a primary fire extinguishing agent. It is traditionally colored red for fast searching in low visibility conditions.
The type of fire extinguisher for a specific object is selected taking into account the place of use, purpose and level of fire hazard.
Fire extinguisher classification
There is a generally accepted classification of fire extinguishers, which distinguishes devices according to their characteristic features:
Activation method:
- automatic – thanks to built-in mechanisms, they are triggered in the presence of irritating factors (smoke or critical temperature rise);
- manual – to activate the device, it is necessary to clamp and hold the lever of the locking and starting device in working condition;
- combined – both automatic and manual activation is possible.
Volume and method of transportation:
- Portable (volume up to 4 liters) – used to extinguish small fires in residential buildings or in vehicles.
- Mobile (volume more than 10 liters) – for easy movement they are attached to the cart, designed for large production facilities.
- Industrial (volume 4-10 l) – in small production halls or office premises.
- Stationary – used at facilities where people are practically not. An example of such a device is the Buran fire extinguisher.
Fire extinguishing agent type:
- Foamy (ORP) – the foam generated when the device is activated is capable of extinguishing solid materials, flammable liquids or gases.
- Air emulsion (OVE) – they can be used to extinguish solid materials and liquid combustible substances.
- Water (OM) – used only when burning solid materials. Extinguishing takes place with water or aqueous solutions of chemicals.
- Carbon dioxide (OU) – the only fire extinguisher of all existing, which can extinguish equipment under voltage up to 10 kW.
- Powder (OP) – an active substance can fight any type of fire, including the combustion of electrical equipment with a voltage of up to 1 kW.
Important! Dry powder extinguishers can be called the most effective, since they can be used to extinguish fires of all types. However, water devices are considered the safest for human health.
This is just a brief reference showing what fire extinguishers are. Next, we will consider the features and nature of the use of each type of device, depending on the contents of the cylinder.
Types of fire extinguishers and their characteristics
It is important to understand that fires of different complexity and nature of ignition are extinguished using different fire extinguishing compositions. For example, a water-based fire extinguisher should not be used to extinguish flaming wiring or flammable liquids.
Therefore, it is worth carefully studying the types of fire extinguishers and the purpose of each type.
Gas
Gas, or carbon dioxide, devices are designed to extinguish all types of fires, except for cases when combustion occurs without oxygen supply. Its work promotes self-elimination of fire by displacing oxygen near the fire source.
When the lever is pressed, the active substance moves along the siphon tube and exits through the bell. Carbon dioxide contained inside the cylinder cools down to -720C under pressure and changes its state of aggregation, turning into a snow-like mass. It lowers the temperature in the spray radius to a safe level.
When working with a carbon dioxide fire extinguisher, never touch the socket with open skin. This can lead to frostbite!
Foam
Such devices are used to extinguish flammable and flammable liquids, solids and materials, as well as electrical appliances without voltage. Not designed to eliminate fires without oxygen.
Foam fire extinguishers are of two types:
- Chemical
– the cylinder contains separate tanks of acid and alkali. When the
locking-trigger device is pressed and the body is turned over, the substances
are mixed with each other, and the foam formed in this way is discharged
through the bell.
- Air-foam – the design contains a gas cylinder and a foam concentrate. After activating the shut-off and trigger mechanism, the high pressure releases the gas cylinder fuse. Further, the gas displaces the foaming agent outward, where it reacts with air, and is converted into a thick foam.
- Scheduled inspection of the device takes place once a year, the frequency of recharging fire extinguishers – once every 5 years.
Powder
• Universal fire extinguishing agent designed to extinguish all types of fires, including flammable and combustible liquids and electrical equipment with voltage up to 1 kW. The extinguishing agent, getting into the fire zone, decomposes and helps to reduce the burning rate.
For effective fire extinguishing, you should adhere to the rules for working with a dry powder fire extinguisher:
- Before
activating the balloon, it is important to ensure that the tubing is not kinked
or twisted.
- When extinguishing flammable liquids, direct the jet directly at the surface of the substance and not at the flame.
- The extinguishing agent should be directed to the nearest fire border, gradually moving further.
- To extinguish electrical equipment, the charge is applied in parts with an interval of up to 5 seconds. In this case, you must not bring the cylinder closer to the fire than 1 meter.
- The fire is extinguished in the direction of the wind.
- If several fire extinguishers are available, it is more efficient to use them together.
- Start extinguishing a vertical fire from the bottom up, do the opposite with flowing liquids.
- The used device must be recharged.
- Important! Even if the fire has been successfully extinguished, you cannot immediately move away or turn away in the other direction. Make sure that combustion does not resume.
Aerosol
The presented devices have automatic or manual control. Designed for extinguishing industrial or residential premises with an area of up to 200 m2. When the mechanism is triggered, a highly dispersed aerosol is released from the cylinder, which can stop and slow down the burning rate.