Several hazards inherent in the technique of surgical skin planing, as described by Kurtin,1 may be eliminated by the substitution of dichlorotetrafluoroethane (commercially known as Freon 114*) for ethyl chloride as the evaporative refrigerant-anesthetic.
Ethyl chloride is inflammable and explosive while Freon 114 is not.2 Ethyl chloride is toxic by inhalation; Freon 114 is less toxic than carbon dioxide. Ethyl chloride acts as a potentially dangerous general anesthetic by inhalation; Freon 114 does not. Ethyl chloride has a much more pronounced (although similar) odor than Freon 114.
Neither ethyl chloride nor Freon 114 has been found to have primary irritant qualities for the skin, or to have initiated allergic sensitization.
The boiling point of ethyl chloride is 12 C (53.6 F), that of Freon 114 is 3.6 C (38.5 F). The critical temperatures and pressures of both substances are similar, so that