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

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Burning electrical wiring is extremely dangerous. Therefore, fire extinguishers must be effective enough to extinguish it. This point is important for any organization or enterprise equipped with electrical installations. Fire safety regulations require fire extinguishers. What should they be? Consider what fire extinguishers can be used to extinguish electrical installations, taking into account their characteristics and the current state of the power grid.

General information

There are a number of factors that make it difficult to extinguish a fire in electrical installations. Due to the high voltage, the extinguishing agents become conductive and re-ignite. Another significant factor is the materials of cable insulation. They are distinguished by highignition temperature and the ability to smolder without oxygen. Therefore, the flame can repeatedly resume after elimination. These factors are fundamental to the question of what types of fire extinguishers can extinguish electrical installations with the greatest efficiency.

About the types of fire extinguishers

Effective fire suppression requires knowledge of the types of fire extinguishers. On sale are models that differ in weight, size, type of basic substance, gas pressure force, area of application, purpose, taking into account the causes of ignition, delivery method, and the possibility of recovery. How to make the right choice?

To get started, to find out which fire extinguishers can extinguish electrical installations of various voltages, you should resort to the following short set of rules:

• for equipment up to 1000 V - powder;
• for equipment up to 10000 V - carbon dioxide;
• for equipment up to 1000 V - carbon dioxide if: the presence of water in carbon dioxide vapor is from 0.006% and above, and the length of the fire extinguishing agent jet is less than 3 meters.

Foam and water fire extinguishing agents (OV, ORP, OCP) are appropriate for fire extinguishing de-energized electrical installations. Permission to use them can be obtained from the authorized section of the electrical network upon confirmation of ignition and disconnection of the equipment from the power supply. The jet of water or foam must be directed precisely at the point of ignition, and not at the spread offlame. Let's consider which fire extinguishers can extinguish a fire in electrical installations (under voltage), as well as with the likelihood of the so-called residual voltage. If it is impossible to de-energize the network, it is permissible to use only a fire extinguisher with an "E" mark on the body, suitable for eliminating accidents in electrical installations.

Water

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

Foamy

Foam fire extinguishers operate on the principle of blocking the access of oxygen, are suitable for extinguishing the burning of liquid and solid materials and are suitable for small areas, within a radius of about a meter. The rules prohibit extinguishing electrical wiring and materials containing potassium, sodium, since when they interact with foam, oxygen is released, which promotes combustion.

Carbon dioxide

These products are suitable for extinguishing fires in electrical installations under voltage, when non-ferrous metals ignite. They are distinguished by the advantage of a low-temperature jet and belong to the gas type. Forbidden usecarbon dioxide fire extinguishers in enclosed spaces, and there is also a risk of skin injury by touching the bell at low temperature. Carbon dioxide fire extinguishing agents are effective for solid, liquid, gaseous substances and extinguishing wires. After using this product, there are no traces left, but the possibility of using it in limited areas is its disadvantage: a large amount of carbon dioxide present in the room can cause poisoning.

Powder

What kind of fire extinguishers can be used to extinguish live electrical installations? Powder fire extinguishers are successfully used as universal ones. The powder present in their composition prevents the access of oxygen to the material, and therefore effectively fights the spread of flame, excluding re-ignition. Fire extinguishers of this type marked OP are in demand in extinguishing cable insulating materials.

The basis of a powder fire extinguisher is mineral s alts mixed with a variety of chemical additives. Fire-fighting agents of this type effectively fight the burning of liquid, solid substances, gases, as well as energized electrical networks. Their use is limited by metals and alkaline earth substances that can burn in the absence of oxygen. To work with powder fire extinguishing agents, a protective mask is required, given the high concentration of dust in the air, and after their use, the room needs to be cleaned from a layer of sprayedpowder.

Types:

• 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 wheels, if the product looks like a trolley, "thrown" into the fire of the product;
• according to the type of active fire-fighting agent: foam (with air - 90% and foam - 20%), suitable for extinguishing fires of classes A, E; gas with carbon dioxide in the composition - classes A, B, E; powder - classes A-D;
• for the displacement of the fire-fighting agent: injection, with liquid gas, thermal, gas generating element, ejector. Gas-spraying fire extinguishers for electrical installations, equipped with a pressure gauge to monitor pressure, are especially in demand;
• in terms of gas pressure height - up to and more than 2.5 MPa at an atmosphere of up to 20 degrees;
• where recoverable, firefighting products range from disposable, non-repairable or refillable, to reusable, made from 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 which fire extinguishers can extinguish electrical installations up to 400 V deserves special attention, since this has to be done under voltage. The fire can be extinguished with a jet of water at a distance of more than 5 meters from the source or with foam. Work should be done with dielectric gloves with a grounded foam generator. Recommendedfire extinguishers marked with the mark OH - freon, water-based, foam with chemical components of OHP, the use of which requires absolute de-energization.

Electrical installations up to 1000 V

What fire extinguishers can extinguish electrical installations up to 1000 V? Dry powder fire extinguishers are recommended, safe for the connected and disconnected electrical networks. The powder mass isolates burning materials from oxygen, also preventing them from smoldering. Permissible distance - from 1 meter.

Electrical installations up to 10 kV

When the equipment voltage is up to 10,000 V, it is necessary to completely turn off the electrical installations, and it is allowed to start eliminating the flame after receiving a signal from an authorized person - a director or a responsible employee about de-energizing the site. If it is impossible to turn off the voltage, carbon dioxide extinguishers are allowed, which are effective for extinguishing metals burning without oxygen.

Fire elimination at the facility

Before the arrival of firefighters, employees at the power facility are required to report the fire to higher persons, and then proceed to eliminate the flame and the consequences of the accident. Before eliminating the accident, it is necessary to obtain permission to carry out restoration work, instruct the personnel on the current situation, clarify which fire extinguishers can be used to extinguish electrical installations, inform about potential threats.

First of all, the shift attendant musttake the following action:

• detect the source of fire, assess the situation, exclude the spread of fire to neighboring objects;
• turn off the power, activate the automatic fire extinguishing system;
• inform firefighters about the location of the fire and grounding of technical equipment;
• indicate the routes of firefighters in the building.

Fire safety skills should be consolidated during the passage of professional briefing together with fire service employees directly at the power facility. The training program should include tactics with grounding fire extinguishing equipment according to the plan developed by the enterprise.