Von Within the 30 months from the end of December 1995, when the German Federal Environmental Agency announced substitute refrigerants for cfc R 12, to the end of June 1998, the operators of refrigeration and air-conditioning equipment with charges larger than 1 kg (except for stand-alone hermetics in which the refrigerant is cycled in an permanently closed loop) had to replace cfc 12 refrigerants. At the beginning 1996 the initial R 12 stock in the three main sectors of commercial refrigeration, mobile air-conditioning and centrifugal compressors was some 6740 t. Until June 1998 53% were replaced, on average. The substitution ratios of commercial refrigeration, mobile air-conditioning and centrifugal chillers show big differences. In the commercial refrigeration 64% of the R 12 initial stock were replaced: 45% by changing the refrigerant in old equipment, 19% by new equipment. The 1.29 million car air-conditioning systems with an initial R 12 stock of 1600 t were substituted by only 7% (112 t). These big differences are supposed to result from the differently severe risks of lacking R 12 refrigerant in commercial refrigeration and in car air-conditioning. In the commerce an equipment stop in consequence of leaked refrigerant could lead to losses of goods and of sales while the same incident for a car driver only means a restriction of his personal comfort. A wide R 12 replacement took place in centrifugal compressors, especially in office buildings and in the chemical industry, containing a total of 1000 t R 12 at the beginning of 1996. The substitiution ratio amounted to 84% (58% exchange in old equipment, 26% replacement by new equipment). The share of R 134a and other pure HFCs in refrigerant replacement figures 54% R 134a and 4% other HFCs, repectively. Drop-in refrigerants with the chorine-containing component R 22 providing technically easy replacement were used to 42%.