R-11, or trichlorofluoromethane, was the first widely used refrigerant. Because of its high boiling point, it can be used in systems with a low operating pressure, making the mechanical design of such systems less demanding than that of higher-pressure refrigerants R-12 or R-22.

Because of the high chlorine content and the ease with which the chlorine atoms can be displaced when the molecule is subject to ultraviolet light, R-11 has the highest ozone depletion potential of any refrigerant.

CAS #75-69-4