Ed,
Someone has to calculate the incident energy to be able to select the correct PPE. It could be anything from voltage rated gloves and tools along with long sleve clothing with a 4 cal rating to the voltage rated tools and gloves with a full "space suit". I would expect that in many cases a 480 volt system would require a minimum of 8 cal rated clothing, cotton underwear, voltage rated tools and gloves and a flash hood. Note that these rules apply to all work on energized equipment including voltage and other types of testing.
Don
