Been there before and I was wearing safety glasses. Ever have a nice hot spark of metal bounce off the corner of the glasses, roll down your face and into your eye somehow? It sucks, but it could have been way worse if those glasses weren't there.
My dad once had a defective grinding wheel explode, shoot up under a face shield, through his throat (just on the inside of the jaw) and up into his mouth :prayer: He was extremely lucky, it only left a scar and didn't hit anything serious on the way through.
I prefer to use an Air Saw anymore for cutting stuff, especially after seeing that happen to my dad. The air saw, with a hacksaw blade for metal from Lowes (I forget the brand/type) doesn't throw sparks, doesn't throw shrapnel if it breaks (they just bend over and then break softly if you happen to damage one severely) and I don't have that tingling feeling on the back of my neck if I'm stuck in a tight space cutting something. :D