Do you ever drive with your shirt off? That would probably be unsafe if you smoked a pipe while doing so, the embers could burn your chest. I passed a man on the highway yesterday driving shirtless (it was a sedan not a pick-up truck) and considered his decision the rest of the drive home. While it was hot here it doesn't seem like it is a good way to deal with the heat, possibly sticking to the vinyl or leather seats or sweating into cloth upholstery. When I am working in the yard, hiking or even at the beach I tend to wear a loose fitting long sleeve shirt and find it to be more comfortable. Maybe when I first started to drive, I drove topless a few times thinking it would add the sex appeal that my second hand Ford Taurus lacked. In hindsight I am happy that I quickly realized this was a bad idea. If I ever saw a pipe smoker driving with their shirt off and found myself stopped at a light next to them, I would certainly not ask what blend they were smoking.