Why is Live-Line Work a Safe Technology?

Why is Live-Line Work a Safe Technology?

Live-line work involves performing operational tasks on electrical power equipment based on an approved procedure, using technical datasheets and knowledge gained through specialized training. It is reserved for qualified and experienced energy sector personnel.

One of the constant hazardous factors in live-line work is the electrical voltage that poses a risk of electric shock. When this is combined with working on loaded circuits, where components are being moved or dismantled, a new hazard emerges - arc flash.

How is Live-Line Work Organized?

The Regulation of the Minister of Energy dated September 25, 2019, regarding occupational health and safety for work with electrical equipment, in § 23, points 1 and 7, permits performing operational tasks using the live-line technique. However, before starting such work, it mandates mandatory training. This training aims to familiarize those assigned to these tasks with the instructions outlining the technology, required tools, and protective measures. Training, based on the "Live-Line Work Organization Instruction," is conducted by instructors specialized in this technique and is intended for experienced electrical fitters who are familiar with the specific type of equipment. Due to the specific nature of network operation and maintenance, individuals responsible for organizing and authorizing live-line work are also required to undergo training.

How is Live-Line Work Performed?

Live-line work is performed using specialized tools and equipment with dielectric properties.

Due to the position of the electrical fitter relative to the potential of the electrical equipment, the following methods are used for performing live-line work:

·       In Contact (also known as the Insulating Gloves Method)

·       From a Distance (Note – a hot stick is a tool, so in terminology, we also use the term "hand tool")

·       On Potential

·       C3M, which is a combination of these methods.

The work method is chosen based on factors such as safety, ergonomics, and the design closely associated with the voltage level of the equipment. The on-potential method cannot be applied to an open overhead line of 0.4 kV AC, while the insulating gloves method is not justified for use on an overhead line of 400 kV AC.

How to Select Appropriate Personal Protective Equipment?

 The selection of equipment for electrical shock protection is relatively straightforward if the appropriate knowledge is available. The physical values that pose an electric shock hazard are constant and easily recognizable (such as device shapes, distances, and constant voltage levels). 

            Selecting equipment for protection against arc flash hazards is a highly complex process. The physical values that pose arc flash hazards are variable and difficult to recognize (such as distances from the power source, methods of power supply, protection systems, and protection settings). To select appropriate PPE, detailed calculations or approximate values derived from calculators are needed. 

How to Minimize Hazards?

 We would like to emphasize that the best method for reducing hazards is to de-energize the installation; however, this does not solve the problem, as this action still requires performing live-line work! In live-line work, it is crucial to strictly follow the established procedures and to be aware that preparatory tasks, isolating the work area, and performing the specific task are equally important. Just as the saying goes, "Vacation begins in the car, not on the beach," it is essential to apply, rather than just possess, the appropriate Personal Protective Equipment (PPE). 

Conclusion

            The fundamental parameter that ensures safety during live-line work is the awareness of the presence of danger. Nothing motivates more than being conscious of a threat. Of course, this danger is minimized through the operator’s knowledge, specialized tools, personal protective equipment, and procedures. However, on the "shoulder" of everyone working in this technology, there is a good spirit that reminds them: you are working live.