If an employee is opening a panel containing 4160v switch gear to open the 250v DC control and then shut the door to hook up a remote rack in device to rack out the breaker or to close the 250v DC control when the breaker is racke in. Is this operator required to wear an Arc Flash suit?

I would think once you open the door, there is an exposure issue.

I would say that if there is no exposed 4160 when opening the door, and you are killing or heating up the DC, since it is over 50 volts, you might need to consider the exposure from that source, but not the 4160.

Alan

Agreed, as long as there are barriers.