Originally Posted by Bullpup Dog
bottom line, shop glasses are made to stop bits of hot steel
Yes. Bits of hot steel, coming from directly at your face on a level plane.
BB's however, come from all sort of fucked up angles, from above and below, slightly behind and in a very dynamic enviroment where you are moving and possible brushing into people and things.
While in a shop you can turn off the machine and everything is safe when it stops moving, unless you are off the field in the safe zone, you can't just stop everything and everyone at an instant whim.
Bottom line. Get the right tools for the right job. Sure your kevlar vest can stop a bullet but it won't do much for a knife.