Noah wrote:
It goes to another extreme. I think that we should consider of putting two labels on equipments. The enclosure does provide some sort of mitigation, but can't eliminate arc completely. Let's compare the safety condition between a driver in the car and a motorcycle driver, don't you think the one inside the car is safer?
I see your point, but you can also argue it is easier to avoid an accident on a motorcycle than in a car.
Some testing has shown that in some cases the closed door can be more dangerous, the enclosure can allow the pressures from the arc to build up before the enclosure fails, resulting in a higher pressure blast with more heat than if the doors were open. Granted, many time the enclosre will not fail, but when it does, kaboom.
We can argue statistics, studies, calculations, etc all we want but no one should argure switchgear, even with the doors closed, should not be considered a hazard.