Recently, a user on the Epilog Laser user group on Facebook posted some photos of a laser that had been used to cut Kydex, a material used for gun holsters, that contains vinyl. When vinyl is burnt, it releases chlorine gas which is horribly corrosive and deadly. Apparently the laser had also been ventilating back into the shop, putting the health of the operators at risk. 

Check out these photos! That's one trashed laser.

Ouch! That's an expensive and deadly mistake to make.