Measures for the protection of the stratospheric ozone layer have led to the phase-out of all chlorinated compounds including hydrochlorofluorocarbons (HCFCs).

• 出于保护大气臭氧层的需要,传统的HCFC类制冷剂R22等已经或者即将停止使用,在制冷空调领域,对于新型环保制冷剂的研究正在兴起。