I run my own little tiny company providing Testing and Commissioning services to the National Grid, specifically on the High Voltage Electricity Transmission Network.
Got a few lads who work with me, great money for outdoor work as no one professional wants to move more than 3 feet from a laptop in a cosy office these days.
Up to 400,000 volts. But anything less than 132,000 volts is for girls. ;-)