Burning electrical wiring is extremely dangerous. Therefore, fire-fighting means for extinguishing it should be quite effective. This moment is important for any organization or enterprise equipped with electrical installations. Fire safety regulations require fire extinguishers. What should they be? Consider what kind of fire extinguishers can extinguish electrical installations, taking into account their characteristics and the current state of the electrical network.
general information
There are a number of factors that complicate fire extinguishing in electrical installations. Due to the high voltage, quenching substances become conductive and able to ignite repeatedly. Another significant factor is cable insulation materials. They have a high ignition temperature and the ability to smolder without oxygen. Therefore, the flame can repeatedly resume after elimination. These factors are fundamental in the question of what types of fire extinguishers can extinguish electrical installations with the greatest efficiency.
About varieties 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 main substance, gas pressure force, area of use, purpose, taking into account the causes of fire, delivery method, and the possibility of recovery. How to make the right choice?
To begin with, in order to sort out what fire extinguishers can extinguish electrical installations of different voltages, it is worth resorting 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 the vapor of carbon dioxide is from 0.006% or more, and the length of the jet of fire-fighting substance is less than 3 meters.
Foam and water extinguishing media (OV, OVP, OHP) are appropriate for fire extinguishing de-energized electrical installations. Permission to use them can be obtained from an authorized section of the power grid when confirming fire and disconnecting equipment from power. A stream of water or foam should be directed precisely at the point of ignition, and not at the areas of flame spread.
Consider which fire extinguishers can extinguish a fire in electrical installations (energized), as well as with the probability 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 housing, 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 eliminate the ignition of materials such as paper, plastic. Solid burning substances must be treated with a directed stream of water. How to extinguish electrical installations with a fire extinguisher, if ignition of flammable liquids is possible? It is allowed to extinguish liquid substances only by spraying drops so as not to provoke their spraying, and specific additional substances should be contained in the water composition.
Foam
Foam fire extinguishers operate on the principle of blocking oxygen access, 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 suppression of electrical wiring and materials containing potassium, sodium, since when they interact with the foam, oxygen is released that promotes combustion.
Carbon dioxide
These tools 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. It is forbidden to use carbon dioxide fire extinguishers in an enclosed space, and there is also a risk of skin damage with touching the bell, which is at low temperature.
Carbon dioxide fire extinguishing agents are effective for solid, liquid, gaseous substances and fire extinguishing. After using this product, there are no traces left, but the possibility of using it in limited areas is its drawback: a large amount of carbon dioxide present in the room can cause poisoning.
Powder
What fire extinguishers can extinguish electrical installations under voltage? Powder extinguishers are successfully used as universal. The powder present in their composition prevents the access of oxygen to the material, and therefore effectively fights the spread of the flame, eliminating re-ignition. Fire extinguishers of this type with OP markings are in demand in extinguishing cable insulation materials.
The basis of a powder fire extinguisher is mineral salts mixed with a variety of chemical additives. Fire extinguishing agents of this type effectively fight the burning of liquid, solid substances, gases, and also electrical networks under voltage. The limitation of their use is 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 large concentration of dust in the air, and after their use the room needs to be cleaned of a layer of sprayed powder.
Kinds:- portable, mobile: up to 20 kg, delivered to the scene of the accident - in the hands, in the form of a satchel behind the back, with the help of wheels, if the product is in the form of a trolley, "thrown" into the fire source;
- 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;
- for the displacement of fire-fighting substances: injection, with liquid gas, thermal, gas-generating element, ejector. Especially demanded are injection fire extinguishers for electrical installations spraying gas, equipped with a pressure gauge for monitoring pressure;
- by height of gas pressure - up to and more than 2.5 MPa at an atmosphere of up to 20 degrees;
- if possible, fire-fighting equipment can be disposable, not repairable or refueling, and reusable, made of durable materials.
Electrical installations up to 400 V
The 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. A fire can be eliminated by a stream of water at a distance of more than 5 meters from the source or with foam. Work should be done with gloves made of dielectric with a grounded foam generator. Fire extinguishers marked with the mark are recommended - chladonic, water-based , foam with the chemical components of , the use of which requires absolute blackout.
Electrical installations up to 1000 V
What fire extinguishers can extinguish electrical installations up to 1000 V? Powder extinguishers that are safe for plugged in and unplugged electrical networks are recommended. The powder mass isolates burning materials from oxygen, preventing them from smoldering. Allowed distance - from 1 meter.
Electrical installations up to 10 kV
With equipment voltages up to 10,000 V, a complete shutdown of electrical installations is necessary, and it is allowed to proceed with the elimination of the flame after receiving a signal from an authorized person - the director or a responsible employee about de-energizing the site. If voltage cut-off is not possible, the use of carbon dioxide quenchers that are effective in extinguishing metals burning without oxygen is permitted.
Elimination of fire at the facility
Prior to the arrival of firefighters, workers at the power plant are required to report the 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 permission to carry out restoration work, instruct personnel about the current situation, clarify which fire extinguishers can extinguish electrical installations, and inform about potential threats.
First of all, the shift duty officer should take the following measures:
- detect a source of ignition, assess the situation, exclude the spread of fire to neighboring objects;
- turn off the voltage, activate the automatic fire extinguishing system ;
- inform firefighters about the location of the fire and the grounding of technical equipment;
- indicate the routes of firefighters in the building.
It is advisable to reinforce fire safety skills during professional training in conjunction with the fire department directly at the energy facility. The training program should include tactics with grounding fire extinguishing equipment according to the plan developed at the enterprise.