I play paintball all the time, and the site where we play requires helmets with face shields.
I played once last winter with my nephew. Man, it get's steamy under that mask/shield. The place where we played said that if anyone took off their mask for ANY reason during play, you'd be kicked out. Sound advise, so it would seem.
All the FReepers who play paintball should get together once each year and have a tournament with all the DUers and KOSers who play paintball.
It would be fun to see if liberals were as bad at paintball as they are at everything else.