essentially a human WDT.
A WHT perhapps?
If you mean someone standing by the main breaker, say so!!
This was standard practice with anything reasonably "hot", but most transmitters, for instance, do have
quite a lot of personnel protection built in.
Thousands of people in Transmitter sites, over decades, worked safely with high voltage equipment by the application of simple safe working rules.
In my own experience, nobody I worked with suffered severe Electric shocks causing injury..
Two people died in aircraft crashes, & two others in falls.
The "Aiieee! The sky is falling!" approach is counterproductive.
Working with high voltages is much less dangerous than the construction industry