Exactly!! Enamals and lacquers are bad enough, but catylized urethanes are a whole new ballgame. These materials will absolutely wreak havoc on your lungs in a way that makes enamals and lacquers seem harmless (they are not!). As you spray this catylized material, the vapors floating around are still in liquid form, and you end up inhaling them. After they are firmy planted in your lungs, they catylize and harden, just as they do on your model, and are there forever. This isn't something to play around with. It can kill you. Be smart, find a way to exhaust these fumes outdoors, andwere a friggin respirator.