On Grinder Safety

Here was the most interesting part of my day (so far):

I work as a 'Student Shop Foreman' in the machine shop of an engineering school.
A guy came in today who's been in pretty regularly in the few weeks I've been working here. He cut up some stainless sheet on the vertical band saw. No big deal.
Then he wanted to use the grinder to remove the burrs.
The only utility grinder we have is monstrous, like 12" wheels.
Sure, I say, just be careful 'cuz that thing can take your hand off.
So I walk away. And before he's even really gotten started, the plate gets snagged and wedges between the grinder support and the grinding wheel. Turned out the gap was set too big. Coulda happened to anybody.
All of us who had been chatting gathered around to watch the grinder spin down, partly out of curiosity, partly out of concern that the situation not get any more interesting.
And then he shows me his hand, which is bleeding from the thumb, cut pretty deep, but thankfully it was the burr that got him, not the grinding wheel.
First aid kit. Alochol wipes, sanitizing spray, gauze, bandages, anitbiotic ointment. Sink. Wash for a few minutes.
He's telling me about how he hates blood and needles and going to the doctor. He's pale in the face. Got him sitting down. He wants the trash can next to him. Turns down water but I send for some anyways.
At this point I'm running worst-case scenarios through my head while I keep pressure on his thumb. It's not a life-threatening cut, but if he passes out, things get more complicated. He could go into shock, and I don't remember exactly how to deal with shock (a blanket over them and call for an ambo maybe).
He ralphs into the trash for a couple minutes, while I change the gauze and maintain pressure. Then he picks his head up, color in his face now, he's back amongst the living, 100% fine.
That's one way to learn how to use a grinder.

Be careful, folks. Mind the grinder gap.