Dichlorodifluoromethane Carbon dichloride difluoride Dichloro-difluoro-methane Difluorodichloromethane Freon 12 R-12 CFC-12 P-12 Propellant 12 ... 760,000 ppm (mouse, 30 min) 800,000 ppm (rabbit, 30 min) 800,000 ppm (guinea pig, 30 min) 600,000 ppm (rat,