Man I could never be a fireman. God bless you man. Takes serious guts and the type of courage I can't even pretend to have.I've seen the damage in motorcycle crashes on the job.
I have seen a beautiful biker babe with both sides of her face ground off (half helmet). Dead dudes in full gear wrapped around light poles.
While I fully support the right to wear whatever you want on/off the bike, I am never without a leather jacket and full face helmet, even on the hottest days in the baking sun. I do not mind sweat- helps to break in the leather and make it buttery soft.
Bones have a tendency to heal just fine, skin grafts look nasty and are very painful.