I do not agree with the determination that there is little chance of an arc flash from happening because the fuses are only 5 amps, since you are exposed to the line side of these fuses and they could very easily flash over on the line side the arc flash calculations would have to be done from this side of the fuse, if these fuses are on different phases then you have the energy that is available from 480 volts, without seeing this installation it would be hard to make any determination of the safety, I would say be safe and turn off the power and LOTOTO, we watched a video of a person who was just testing a 480 volt 30 amp disconnect and while holding the leads to his meter he also has his screw driver that he used to turn the safety release so he could open the door of the disconnect in his hand, the screw driver made contact from the bar that pulls out the contacts and the middle phase on the line side of the fuse, it blew and burned him really bad right in the face, and the disconnect only had 10 amp fuses in it, but the disconnect was only 5 feet from the 2k amp MDP that fed it and was fed with 10 awg conductors, so there was a lot of incident energy available.