What kind of fire extinguishers can be used to extinguish electrical installations in case of fire?

Burning electrical wiring is extremely dangerous. Therefore, firefighting means to extinguish it must be sufficiently effective. This moment is important for any organization or enterprise equipped with electrical installations. Fire safety rules require the presence of fire extinguishers. What should they be like? Let's consider what extinguishers can extinguish electrical installations taking into account their characteristics and the current state of the electricity network. general information

There are a number of factors that complicate fire extinguishing in electrical installations. Because of the high voltage, the quenching agents become electrically conductive and can be ignited repeatedly. Another significant factor is the cable insulation materials. They have a high fire temperature and the ability to smolder without oxygen. Therefore, the flame can repeatedly resume after liquidation. These factors are fundamental in the question of what types of extinguishers can be used to extinguish electrical installations with the greatest efficiency.

On the types of fire extinguishers

Effective elimination of fire requires knowledge of the types of fire extinguishers. On sale are models differing in weight, size, type of base material, gas pressure force, application area, purpose in view of the causes of ignition, the method of delivery, the possibility of recovery. How to make the right choice?

First, in order to find out what fire extinguishers can be used to extinguish electrical installations of various voltages, one should resort to the following brief set of rules:

• For equipment up to 1000 V - powder;
• For equipment up to 10000 V - carbon dioxide;
• For equipment up to 1000 V - with carbon dioxide, if: the presence of water in carbon dioxide vapor is from 0.006% and higher, and the length of the jet of a fire-fighting substance is less than 3 meters.

Foam and water extinguishing means (OB, ORP, OHP) are appropriate for fire fighting of de-energized electrical installations. Permission for their use can be obtained from the authorized site of the power grid upon acknowledgment of fire and disconnection of the equipment from power supply. A jet of water or foam should be directed to the point of ignition, and not to areas of flame propagation.

Let's consider what kind of fire extinguishers you can extinguish a fire in electrical installations (under voltage), as well as with the probability of a so-called residual voltage. If it is not possible to de-energize the network, it is acceptable to use only a fire extinguisher marked "E" on the housing, suitable for eliminating accidents on electrical installations.

Water

Their action is based on spraying or supplying water in the form of a high-pressure jet. With their help eliminate the ignition of materials such as paper, plastic. Solid burning substances must be treated with a directed water jet. What kind of fire extinguisher to extinguish electrical installations, if the ignition of flammable liquids is not ruled out? Liquid substances are allowed to be extinguished only by spraying droplets, so as not to provoke their spraying, and as a part of the water, specific additional substances must be contained.

Foamy

Foam extinguishers act on the principle of oxygen barrier, are suitable for eliminating the burning of liquid and solid materials and are suitable for small areas, within a radius of about a meter. The rules prohibit the damping of electrical wiring and materials containing potassium, sodium, because when they interact with the foam, oxygen is released, contributing to combustion.

Carbon dioxide

These means are suitable for extinguishing a fire in electrical installations under voltage, with the ignition of non-ferrous metals. They are distinguished by the advantage of a low-temperature jet and belong to the gas stream. It is forbidden to use carbon dioxide fire extinguishers in an enclosed space, and there is a risk of damage to the skin by touching the bell that is at a low temperature.

Carbon dioxide fire extinguishing agents are effective for solid, liquid, gaseous substances and extinguishing wiring. After using this product there are no traces, but the possibility of using it in limited areas is its drawback: the large amount of carbon dioxide present in the room can cause poisoning.

Powder

What extinguishers can be used to extinguish electrical installations under voltage? Powder extinguishers are successfully used as universal. Powder, present in their composition, prevents access of oxygen to the material, and therefore effectively fights the spread of the flame, eliminating re-ignition. Fire extinguishers of this type with marking OP are in demand in extinguishing cable insulation materials.

The basis of the powder fire extinguisher - mineral salts, mixed with a variety of chemical additives. Fire fighting means of this kind effectively combat the burning of liquid, solid substances, gases, as well as electrical circuits under voltage. Restriction of their use are metals and alkaline-earth substances, capable of burning in the absence of oxygen. To work with powder fire extinguishing means a protective mask is required, taking into account the high concentration of dust in the air, and after their application the room needs to be cleaned of the layer of powdered powder.

Kinds:

• Portable, mobile: up to 20 kg, delivered to the scene - in the hands, in the form of a knapsack behind the back, with the help of castors, if the tool looks like a cart, "thrown" into the source of ignition;
• By type of active fire-fighting substance: foam (with air - 90% and foam - 20%), suitable for eliminating fires of classes A, E; Gas with carbon dioxide in the composition - classes A, B, E; Powder - classes A-D;
• On the replacement of fire-fighting substance: quenching, with liquid gas, thermal, gas-generating element, ejector. Particularly in demand for fire extinguishers for electrical installations, spraying gas, equipped with a pressure gauge to monitor the pressure;
• On the height of gas pressure - up to and above 2.5 MPa at an atmosphere of up to 20 degrees;
• As far as possible, fire-fighting means are disposable, not subject to repair or refueling, and reusable, made of durable materials.

Electrical installations up to 400 V

Technological requirements for substations of this type are such that they are not de-energized, despite the occurrence of a fire. Therefore, the question of what extinguishers can be used to extinguish electrical installations up to 400 V, deserves special attention, since it has to be done under tension. The fire can be eliminated by a jet of water at a distance of more than 5 meters from the source or foam. Work should be in gloves made of dielectric with a grounded foam generator. Recommended extinguishers marked with the mark OX - cold, aqueous OM, foam with chemical components of OHP, which require absolute de-energizing.

Electrical installations up to 1000 V

What extinguishers can extinguish electrical installations up to 1000 V? Recommended powder fire extinguishers, safe for connected and disconnected electrical networks. The powder mass isolates burning materials from oxygen, preventing also their decay. The allowed distance is from 1 meter.

Electrical installations up to 10 kW

When the voltage of the equipment is up to 10 000 V, the electrical installations must be completely disconnected, and the flame can be eliminated after receiving a signal from the authorized person - the director or the responsible officer - to de-energize the site. If the voltage is not switched off, the use of carbon dioxide extinguishers effective for extinguishing burning oxygen-free metals is permitted.

Elimination of fire at the site

Before the arrival of firefighters, workers at the power facility are required to report a fire to their superiors, and then proceed to eliminate the flame and the consequences of the accident.

Before eliminating the accident, it is necessary to obtain admission for rehabilitation work, to instruct the staff about the current situation, to specify what fire extinguishers can extinguish electrical installations, inform about potential threats.

First of all, the shift attendant should take the following measures:

• To detect a fire, to assess the situation, to exclude the spread of fire to neighboring objects;
• Turn off the voltage, activate the automatic fire extinguishing system;
• Inform firefighters about fire localization and grounding of technical equipment;
• Indicate the routes of movement of firefighters in the building.

Fire safety skills should be fixed during the professional briefing together with the fire department staff directly at the energy facility. The training program should include tactical methods with grounding of fire extinguishing means according to the plan developed at the enterprise.