The main causes of electric shock on the street

Electricity not only brings us great benefits, greatly facilitating the human life, but also carries a serious threat. The energy companies supplying it pay a lot of attention to resolving security issues, and spend enormous material resources on its observance.

However, accidents with people from exposure to electricity continue.

Possible causes of electrical injuries in everyday life are considered. separate article. And here we touch on the features of electric shock on people on the street.

Unauthorized entry into the territory of energy facilities

All electrical installations are made inaccessible to unauthorized visits by unauthorized persons, and live objects are fenced, placed in separate buildings or located at a height.

The photograph below shows the fencing of a high-voltage switchgear, which is located around the entire perimeter of the substation.

You can’t penetrate him. It is life threatening. But, practice shows that a certain category of “non-ferrous metal lovers” violates this rule.

In reviews of accidents, you can find the facts of unauthorized penetration of "electricians" for such fences, which ended tragically.

The episode of getting into the KRUN-10kV of a recently hired electrician of the housing and communal services, who unauthorizedly opened the locks, pulled out a 220-volt Chinese indicator screwdriver from his pocket and began to check for voltage on the tires. There his remains were found by an out-of-command brigade, who came to deal with emergency shutdowns that occurred in KRUN.

Power line climbing

The wires of overhead power lines are located at a safe height for people who are standing on the ground. As a rule, for the calculation taken degraded meteorological indicators for a particular area. But the weather can always make adjustments to the dielectric properties of the air, which are significantly reduced:

• in dense fog;

• during a thunderstorm;

• in rain and some other cases.

The photo shows an aerial power line-330kV, which rises above the surrounding forest.

But, if a person decides to climb on such a support, then, most likely, the outcome is predictable - he will create a short circuit to the ground with his body and burn out.

Aerial vehicles, cranes, lifting equipment under such lines must pass with the working bodies, transferred to the transport position and only in places designated for them.

By the way, such lines create a very high potential induced voltage. Being under its action is extremely undesirable for health. Recently, returning from picking mushrooms on a bicycle along a forest road crossing VL-330kV, I felt a characteristic “tingling” of my fingers. I kept them on the steering wheel near the speed switches and brake levers. Immediately I had to remove my fingers on the dielectric plastic handles and quickly drive through this dangerous place.

When an agricultural worker under such a line begins to climb the bunker of a combine harvester, a very bad case can happen to him.

Design flaws of power supply facilities

Reduced height of electrical objects

The security photo below can be interpreted in two ways:

• formally dangerous electrical device - the transformer is located at a height and warning signs are made around it about the prohibition of approaching;

• behind the scenes - this height is not more than the height of an adult, and the side corner holders allow you to conveniently put your foot so that you can climb onto such a structure.

Of course, an adult will not climb here and risk his life. And what will a teenager do during the excitement of outdoor games or in a fit of demonstration of his courage in front of peers?

Similar designs of transformers are already becoming obsolete and are gradually being replaced with safer ones. But while they still pose a certain threat to people.

Breakdowns and malfunctions

All energy facilities are created with a certain margin of safety and for a long time fulfill their mission, working reliably and efficiently. But, like any technical device, they are prone to breakdowns and malfunctions.

Quite often, severe weather anomalies create emergency situations on overhead power lines, when a wire break occurs due to excessive mechanical loads.

In electrical networks, energy transfer systems are used:

• with grounded neutral;

• or with deaf isolation.

Depending on this protection, they can quickly disconnect the voltage from the emergency line or not work at all. This means that a life-threatening potential will be present on such a wire lying on the ground.

It can affect the "step voltage", which will cause the defeat of the person. The rules prohibit approaching such places at a distance of less than 10 meters without special protection.

A dangling conductor may be poorly visible in areas overgrown with grass. Therefore, when staying near power lines, you must always be careful, cautious, and instill these feelings in your children.

Violation of rules of conduct near electrical objects

Developed on the basis of numerous tragedies, standards of behavior and current safety rules prohibit in any way affect the electrical resistance of the air gap both between the wires themselves and with respect to them and the ground.

However, the “teenage pranks” that try to break the glass insulators of voltage lines of high voltage lines still occur. Sometimes such hooligans receive electrical injuries.

Violations should be singled out in a special series when a person simply does not suspect the danger of electricity lurking around him, being under the influence of very different feelings near the poles of power lines. These include:

• fishing with a fishing rod;

• games with kites;

• making bonfires.

What is the danger of fishing near power lines

The average height of the wires of the overhead power lines is about 10 meters. The length of the telescopic rod of a modern fishing rod is usually 5 meters. If the fishing line is tied to the tip of the rod, then the total removal of the fishing hook from the fisherman’s hand is already 10 meters.

To this distance is added the height of a person and an arm extended for casting. And if you consider that modern fishing rods are equipped with inertia-free reels for long-range throwing of several tens of meters, it becomes clear why you can hook a wire onto a hook.

At the same time, the high-voltage potential of the line will drain to the ground along a wet fishing line through the body of an unlucky fisherman.

On the power transmission towers installed near water bodies, power engineers put up warning signs about the hidden danger of fishing. First of all, warnings appeared where similar misfortunes had already occurred.

However, for some reason, individual people, ignoring the inscriptions, continue to risk their own lives.

Kids games with a kite

Teenagers love outdoor games. Running a snake they really like. But, an adult, buying such toys for a child, must not only show how to use them, but also explain the safety rules, determine the area where you can play and indicate restricted areas.

A snake can rise to a great height, and its control, especially with children's hands, is not always predictable. When it touches the wire or even a simple approximation, a breakdown of the insulation of the air gap occurs, which will lead to electrical injury to the child by the line potential through the cord.

Kite games near power lines are prohibited.

Bonfire

During the combustion of firewood, smoke is formed, consisting of solid and fine particles in suspension. They do not settle by gravity, but rise upward or are slightly blown away.

Smoke particles reduce the electrical resistance of air. Through them, a breakdown of insulation is possible.

Making fires near existing power lines is prohibited by the rules.

Electric transport

Railway trains, trams and trolley buses for energy receive energy from a contact wire or rail, which are at high potential. One of the options for this design is shown in the picture.

It demonstrates that voltage is present not only on the contact wire, but also on the carrier cable with which it is connected by strings. Therefore, they are separated from the supports by a system of insulators. In railway electrified vehicles, despite constant public warnings about the dangers of travel on the roofs of cars, there are cases of death due to electric current. Indeed, in Russia two dangerous voltage sources are used for electric trains:

1. 3.3kV DC;

2.27kV at a frequency of 50Hz.

However, not all people, especially adolescents, correctly perceive this information. And the desire to show off before peers with their dashing often ends tragically.

For trolleybuses and trams that are consumers of electric energy, a malfunction is possible - a breakdown of the insulation of electrical equipment to the building. At the same time, transport on wheels with rubber tires will become more dangerous: its body is isolated from the ground. At the entrance / exit, when a person makes contact with the ground with one foot and the trolleybus with the other, there is a danger of electric injury. You can avoid it by jumping.

The body of the tram by means of iron wheels moving on rails is constantly grounded and less dangerous.

In order to avoid electric shock on the street, it is necessary not only to present the possible causes of danger, but also to constantly pay attention and caution.