At all times, fires threatened human life, and rescuers were looking for a means to eliminate them. Fire extinguishers have become an indispensable device for firefighters in the fight against fire. In the article, we consider such a type of fire extinguisher as air-emulsion, its advantages and disadvantages, as well as popular models.
Description and features of a fire extinguisher
Emulsion fire extinguisher (OVE) - the most effective, environmentally friendly and safe for humans extinguishing fires. It is an improved modification of an air-foam fire extinguisher. In addition to surfactants, the composition of its extinguishing mixture also includes antifreeze and various components that make it possible to obtain an aqueous emulsion. This improvement has greatly expanded the range of applications of this tool.
A fire extinguisher, unlike other varieties, is reusable (refueling can be done up to 40 times). Its main significant differences are the ability to extinguish liquids and electrical equipment, as well as the ability to function properly in the widest range of climatic conditions.
Also, experts note that this device has high values of the protected area: for one HE-extinguisher with a volume of 5-6 liters, this figure reaches 100 square meters.
Purpose and scope
Due to the unique physical properties of the emulsion, this fire extinguisher is used to extinguish a wide variety of foci:
- Class "A" and "B". A fire extinguisher is indispensable for eliminating fires resulting from the ignition of both solid and liquid combustible substances.
- Class "E". A fire extinguisher is used to extinguish electrical equipment under high voltage (up to 10 thousand V).
OVE fire extinguisher can be used in a variety of weather conditions, in temperature ranges from -40 to +50 degrees.
It is used in residential premises and social facilities with an increased number of people, as well as for the protection of public and personal transport.
Device and principle of operation
The design of an air-emulsion fire extinguisher (OVE) is generally similar in structure to fire extinguishers containing other active substances in the composition:
- the cylinder is made of welded steel sheet, it is a fairly lightweight material, respectively, the fire extinguisher has a fairly small weight;
- According to the type of overpressure source used, the HE-extinguishers can be of two varieties: injection (the pressure creates a layer of compressed gas that is pumped into the cylinder over the extinguishing composition) or equipped with a separate canister connected to the trigger;
- when the locking and starting device is activated, the emulsion is advanced through a siphon tube and then through a rubber hose to the atomizer, with the help of which it is sprayed, mixed with air, onto the foci of combustion.
The cylinder of the fire extinguisher is coated with powder enamel, which gives it high resistance to mechanical damage and adverse weather conditions. Inside the cylinder is treated with an anti-corrosion compound.
The fire extinguisher OVE special composition of the extinguishing substance, which distinguishes it from others. This emulsion is an aqueous solution of surfactants. Such a mixture is well distributed and mixed with air, which increases the length of the jet (this allows you to be at a remote safe distance from the source when extinguishing) and high efficiency of exposure to the burning area. Extinguishing occurs immediately when the emulsion enters the ignition area. The cessation of the combustion process occurs as a result of the fact that the emulsion creates a film on the surface under which the burning surface is cooled. In addition, the resulting film effectively precipitates combustion products that are toxic to humans , and prevents re-ignition.
Terms of Use
In order for the fire extinguisher to not be spoiled ahead of time and effectively perform its functions, it is necessary to observe the list of rules:
- to bring the fire extinguisher to work, it is necessary to break the seal and pull out the safety pin;
- point the spray gun at the ignition area and press the start lever; the charge with the emulsion takes off due to the excess pressure created by the layer of compressed gas.
When using a fire extinguisher, it is prohibited:
- to hit him;
- use a cylinder if mechanical damage is visible;
- direct to people.
OVE must be sealed and have a receipt of the manufacturer.
The device has a long service life, it does not need to be reevaluated, and reloading of the OVE fire extinguisher may not be carried out for 10 years (40 recharges are allowed for the entire service life).
To monitor the health of this device, it is quite simple from time to time to carry out visual control of the barometer scale.
Advantages and disadvantages
OVE fire extinguisher, due to its special composition - emulsion, combines the positive qualities of water and air-foam fire extinguishers, while it does not have the disadvantages that these devices have. Its advantages:
- The highest efficiency and universal application in comparison with other types of fire extinguishers;
- environmental safety: harmless to human health, and also does not damage material property in the fire extinguishing center, does not harm the environment;
- large protected area;
- when extinguished, it does not create dust, thereby does not impair visibility;
- does not increase the amount of carbon dioxide when ignited in an enclosed space;
- you can start extinguishing immediately, without personal protective equipment, in the presence of people, right during the evacuation;
- the ability to extinguish objects under electrical voltage;
- the possibility of use at low ambient temperatures;
- long service life.
The main disadvantage is the high cost. But it is justified by the effectiveness of the fire extinguisher. The device can replace several tens of foam analogues during the service.
Manufacturers and models
The leaders in product popularity are Russian companies Rusintek, Bontel, Samurai, and NPO Pulse. These manufacturers offer a wide selection of models that differ in charge weight in the range from 2 to 50 kg.
Small cylinders (2 or 4 kg) are ideal for the interior of the car. Characteristics of OVE fire extinguishers:
- working pressure - 1.85 MPa;
- use temperature from -40 to +50 ° ;
- the duration of the jet - not less than 12 seconds;
- fire extinguishing efficiency - 2A (class A), 55V (class B), up to 1000V (class E).
Cylinders of 8, 10, 40 and 50 kg are more often installed in large areas - warehouses, hangars, etc. Cylinders with a high mass of charge, from 10 kg and above, are mobile, that is, equipped with a trolley for ease of use. The most popular models for household use are five- and six-kilogram fire extinguishers.
Of the imported models, the device of the MiniBombero company (Spain), which has a very compact size, with a charge volume of 250 ml, is noteworthy.
Kingsway Industries TRI-MAX fire extinguishers feature a case for storing the appliance. These models are lightweight and easy to use.
The extinguishers of the British company Angus Fire are also known around the world. They have a difference in weight and volume, but all devices do an excellent job of extinguishing the same materials.
We can say that a fire extinguisher is an integral part of ensuring the safety of any room. Standards established the mandatory availability of this device, as well as its timely verification and recharging.