Power line security zone: building a house according to SanPiN standards and harm to health

When an electric current of high voltage passes around the conductor, an electromagnetic field harmful to the body is formed. SanPiN norms have been calculated and introduced to protect a person from this radiation. They indicate safe distances for living from electric lines to residential buildings, taking into account the voltage in the network. What is the protection zone of a power transmission line, is it possible to carry out construction and work in it, and how this impact is measured – later in the article.

The consequences of exposure to an electromagnetic field on the human body

After numerous experiments and observations, it is proved that:

• Electromagnetic fields induce both potential differences and currents in the human body. Short-term exposure to such values ​​is not hazardous to health, but prolonged exposure to radiation can seriously disrupt the functioning of internal organs.
• A long period under electromagnetic radiation leads to an increase in body temperature – a very doubtful and unproven fact, and today it exists only as a theory.
• Even weak, but long-term radiation from power lines leads to an increase in migraines and headaches, dizziness, sleep disturbance, a constant feeling of fatigue, and incorrect functioning of the entire nervous system.

Studies have been carried out in the field of the impact of electromagnetic radiation on the body of pregnant women. Conclusion: an increase in the number of premature births, miscarriages, too low weight of newborn babies. Prolonged exposure to the field is one of the causes of cancer.

The impact on a person of power lines is also characterized by the flux density of magnetic induction. This is a value measured in Tesla. For a person, the normal level is 0,2 – 0,3 μT (microTesla), but these are foreign studies not accepted in Russia. We don’t have a standard for this.

Important! Knowing the safe distance at which to be from the line, you can save not only your health, but also life.

Regulations

The main regulatory document in determining the security zone of a power line is GOST 12.1.051-90, which describes in detail the safe distance. A separate item is devoted to the safety of work in the zone of the appearance of an electromagnetic field around power lines.

With regard to the protection of human health, SanPiN norms were introduced. With their introduction, the construction of power lines inside the sanitary protection zones was already prohibited and safe values ​​​​of electric fields were indicated. SanPiN 2971-84, which have been in force for quite a long time, has now lost its force and has been replaced by a new document SanPiN 2.1.2.1002-00 regulating the construction of SNT and IZHS.

What is a security zone and where is it established

The protection zone of a power transmission line is a conditional plane laid at a certain distance from power lines, the long crossing of which can adversely affect human health.

Features of determining the security zone of a power transmission line in accordance with GOST 12.1.051-90:

• The concept of a security zone refers to the space from the power line to the ground.
• The territory with increased danger to the human body is enclosed by two conditional planes passing vertically, to the left and to the right of the power transmission line.

Important! Conditional planes do not pass from the cables themselves, but at a distance from them determined by GOST 12.1.051-90.

• If the power line is laid over a lake, river, or other type of reservoir, then the imaginary planes for navigable reservoirs are determined at a distance of 100 m from the line cables, and for non-navigable ones – the same as for the space above the ground.
• Distance from cables for underground power lines – at least 1 m.
• Distance from underwater power lines – 100 m.

Do not confuse the concepts of a protected zone and an area where there is a high probability of receiving an electric shock. Such a probability is excluded or minimized by strict adherence to the rules for the design of power transmission lines, which must be strictly adhered to during the construction of power lines.

Security zone depending on line voltage

GOST 12.1.051-90 determines the distance from the extreme cables of the power line, depending on the voltage of the power transmission line. On the existing lines, the boundaries of the sanitary protection zones are determined by the criteria of the electric field strength – 1 kV / m.

1. Up to 20 kV – 10 m.
2. From 20 to 35 kV – 15 m.
3. From 35 to 110 kV – 20 m.
4. From 110 to 220 kV – 25 m.
5. From 220 to 500 kV – 30 m.
6. From 500 to 750 kV – 40 m.
7. From 750 to 1150 kV – 55 m.

Visually postponing the above distances from the power transmission line (depending on the voltage of the line), it is necessary to immediately carry out conditional vertical projections on the ground – this will be the boundary of the security zone. For greater safety and health, do not stay in such areas for a long time. Building under power lines is prohibited.

We determine the voltage of power lines by appearance

If a high-voltage line passes near your house, you can determine its voltage by its appearance. The most common in settlements are poles of 0,4 and 10 kilovolt lines.

Supports with voltage up to 0,4 kV also have a security zone equal to 2 meters. Most often, cities are wired with SIP wire, as well as aluminum wire on low supports with small white, brown or glass insulators.

The poles of a 10 kV transmission line are distinguished by larger brown insulators, and the height is about 9 meters.

Air – 35, 110 and 220 kV have one wire per phase. 330 kV is 2 wires, 500 kV is 3 wires, and 750 kV is 4 or 5 wires. They also differ in the number of insulators in garlands: 35 kV 3-5 pieces, 110 kV 6-8 pieces, 220 kV 10-15 pieces, VL-500 kV from 20 and VL-750 kV more than 20 pieces.

How to work in protected areas

A long stay in areas close to power lines leads to disruption of the human body, deterioration of well-being and health. The need for any installation or construction work implies compliance with certain security measures.

Before carrying out work in security zones, all the requirements of GOST 12.1.019 must be met. If it is not possible to turn off the line, it is necessary to issue protective equipment to the working personnel, install a protective fence, and ensure complete isolation of the workplace.

If there is an increased risk of touching current-carrying parts, protective earthing or grounding of the line should be provided. Use special instruments to measure the insulation resistance. Depending on the situation, protective equipment can be used either individually or all together.

Necessarily! Before starting work, a safety briefing must be carried out. If necessary, the personnel are also checked for knowledge of the basic safety rules or proper instructions.

Before carrying out earthworks, it is necessary to make sure that high-voltage lines are not laid in this place. Very often, an excavator becomes the cause of a serious short circuit, in which not only equipment, but also the health of the excavator himself can suffer.

If your house was built in a protected area, but before the construction of the overhead line, the contractor performing the work must agree on the work being carried out.

What actions are prohibited in the security zone of power lines

High voltage, under which power lines are located, is a direct threat to the life and health of both maintenance personnel and random people who ignore safety regulations. To minimize accidents, as well as disruptions in the operation of power lines, GOST 12.1.051-90 provides for a list of actions that are prohibited in the security zone.

In the security zone of power lines of any voltage, it is prohibited:

1. Construction, overhaul, demolition of buildings or structures.
2. Establish storage of fuels and lubricants, due to the possibility of unintentional ignition or fire. It is also forbidden to drain spent fuel and lubricants from nearby storage bases into the security zone of the power line.
3. Place dumps or places of large accumulation of both construction and household or industrial waste.
4. Build a gas station.
5. Carry out work using explosive or combustible substances. Also, fires are prohibited.
6. It is strictly forbidden to throw conductors on wires of both high and low voltage in order to attempt to steal electricity. This can lead to an accident, and in the case of high voltage power lines, to death.

GOST 12.1.051-90 prohibits repair work on overhead power lines during thunderstorms or rain. If the power transmission line has an important status and its inaction can disrupt the work of serious industrial or state enterprises, then repair work on it is allowed only when the voltage is off. When working on overhead lines without contact with conductors, the distance from a person to the nearest cable must be at least two meters.

Work under voltage, with all technical means of protection, is allowed only in two cases: when the water jet rises no more than 3 meters from the ground or when the water jet does not enter the security zone of the power line.

In the security zone of power transmission lines, without the permission of the organizations operating them, no work is allowed. The list also includes items such as digging up land or laying out road lines.

A separate item is the use of turnout cranes near power lines. The optimal distance at which such equipment can operate is at least 30 m. If, however, it is impossible to carry out work without a crane, then this is displayed in the work permit – a special document issued to the crane operator.

Basic safety rules when staying in the security zone of power lines

There are situations when it is not possible to bypass the security zone of power lines, for example, on rough terrain or close proximity to the power line of reservoirs. In this case, you should follow simple safety rules, and, if possible, stay away from the territory where the power line passes for a long time.

In no case should a wire lying on the ground be approached. It is impossible to visually determine whether it is energized or not, therefore the optimal and safe distance is at least 8 m. If the distance from the person to the cable is less, then you should leave the danger zone as quickly as possible, but in small steps, without taking your feet off the ground, since in this situation, step-by-step tension appears, which can be critical to life or health.

If a strongly sagging wire is noticed when passing the security zone of an overhead power line, then you cannot move under it. The design of an overhead transmission line provides for its distance from the cables to the ground, taking into account such an important factor as the magnitude of the operating voltage. Therefore, violation of the distance from the wire to the ground can lead to electric shock.

Before passing the security zone of the power line, you should visually verify that there are no line faults. Sparking or short-term arcing means that the power line is in an emergency condition and being near it is life-threatening.