only thing that ever sent me to the hospital after worrying about table saws, routers, CMS, etc. was a low speed belt sander sanding metal. It was just fast enough to loft dust up onto my eyeball and get one of the round particles to stick in the surface. I couldn't believe it - it just felt like an unexpected spit of dust in the face (like you get in a breeze outside) and when I was done working, I could see a little shiny grain of it on the dark part of my eye.
No matter what i'm doing, if it's more than hand planing - I always have some kind of glasses on now (I didn't wear them back then, but now have plastic lens glasses) so that there is no straight line of travel from the workpiece to my eyeballs.
Getting the metal pushed off of the surface of my eyeball was no big deal, but it did take 3 hours in the ER and ultimately required dilation, numbing of my eyeball and sitting and watching the ER doc literally pick the bit off of the surface with a needle. And listening to people in adjacent rooms who were on bad drug trips while I waited. Since this is the USA and our hospitals spend money hand over fist, the ER had several outfitted rooms that were intended only to deal with eye emergencies - I don't think lots of it was needed, but did have the opportunity to have the docs check over my entire eyeballs to make sure that the spot I knew of was the only one - apparently, people go in with slivers of metal they're unaware of on top of what they can see.
