Live-line working

[1] In general, it is impossible to determine visually whether electrical equipment is energized; in any event, it is often necessary to maintain or repair circuits while they are in operation.

[2] The sticks enabled the linemen to carry out the work without infringing on the minimum clearance distances from live equipment.

With the advent of fibreglass poles in the late 1950s, which neither split nor soaked up rainwater, utilities were prepared to carry out hot-stick working to their highest operating voltages, perhaps 765 kV.

More sophisticated poles can accept pneumatically or hydraulically driven power tools which allow, for example, bolts to be unscrewed remotely.

[3] Usually applied for work above 1 kV AC 1.5 kV DC The primary classes are: [citation needed] Gloves protect the worker from exposure to the live part being worked upon sometimes referred to as the 1st point of contact; the point where current would enter the body should an inadvertent contact be made.

Bare-hand, or potential working involves placing the worker in direct electrical contact with an energized overhead line.

Barehand working provides the lineworker with greater dexterity than the hot stick method, and may be the preferred option if conditions permit it.

[4] With this technique, insulator strings, conductor spacers and vibration dampers can be replaced, or lines spliced, without any loss of supply.

[4] The strong electric field surrounding charged equipment is enough to drive a current of approximately 15 μA for each kV·m−1 through a human body.