Safety is of the utmost concern. Thus, there is a lot of gear each man needs carry/wear to protect himself when working wire. After all, those lines can carry huge amounts of wattage.

Overhead power transmission lines are classified in the electrical power industry by the range of voltages:
Low voltage – less than 1000 volts, used for connection between a residential or small commercial customer and the utility.
Medium Voltage (Distribution) – between 1000 volts (1000 volts = 1 kV) up to about 33 kV, used for distribution in urban and rural areas.
High Voltage (subtransmission less than 100 kV; subtransmission or transmission at voltage such as 115 kV and 138 kV), used for sub-transmission and transmission of bulk quantities of electric power and connection to very large consumers.
Extra High Voltage (transmission) – over 230 kV, up to about 800 kV, used for long distance, very high power transmission.
Ultra High Voltage – higher than 800 kV. (that's 8,000,000 volts!)

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