Work on power lines and equipment is particularly dangerous. They may be carried out on the basis of the Safe Execution Instructions, which is annexed to the Safety and Health Plan, or on written instructions if they do not concern the construction site.

All work in the danger zone of active power lines may be carried out only in exceptional situations and on the written instructions of the person in charge or supervising the operation of the equipment. An additional requirement is the establishment of a person supervising the course of work, who must have supervision powers.

Before proceeding with electricity works, it is necessary to identify and inventory the running lines and recognize the user of the line. On the routes identified underground power lines should be placed plaques about the danger of electric shock. Before the intersection of transport lines with overhead lines, gates shall be set to limit the permissible dimensions of passing vehicles.

Those supervising work on power lines should ensure that they are carried out only with the voltage off. In case of the need to carry out works on an active line, safe working conditions must be agreed with the user. All activities, considered to be particularly hazardous, shall be carried out in a minimum of two persons, providing technical means for the safe performance of the work, as well as reassurance and first aid in the event of danger.

The width of the danger zone depends on the type and voltage of the power lines and the type of work performed. It should be measured horizontally from the extreme wire of the line and on both sides of the line. When working within an active line, workstations must not be placed directly below it and the distance from the extreme lines must not be less than the limits of the width of the danger zones:

• for low voltage lines not exceeding 1 kV – 3 m;
• for high voltage lines from 1 kV to 15 kV – 5 m;
• for high voltage lines from 15 kV to 30 kV – 10 m;
• for high voltage lines from 30 kV to 110 kV – 15 m;
• for high-voltage lines above 110 kV – 30 m.

Danger zones should also be appropriately marked and, in the case of work at dusk, illuminated in such a way that the plates can be read.

For cable lines, the danger zone should be marked on both sides of the cable at a width of 6 m. The route of the cable lines laid underground must be marked in an appropriate manner. Visible signs should be arranged in places of change of the course of the line, and on straight sections – not less than every 20 m.

In a danger zone of cable lines, earthmechanised earthwork may only be carried out on the written instructions of an authorised person supervising or in charge of the operation of power equipment.

When working near power lines, it shall be prohibited to place workstations or machinery directly under overhead power lines and at a distance less than that laid down by specific provisions. In addition, it is not advisable to perform such works without the developed IBWR materials and in a single-person cast.

Source: https://www.bhp-center.com.pl/bezpieczenstwo-prac-w-poblizu-linii-elektroenergetycznych/