HCFC and CFC phase out
The introduction of CFCs and later on HCFCs did solve important safety problems during the first part of the last century, but environmental risks were not considered until the mid-1970s. At this stage, the severe consequences of a continued use of especially the CFCs became obvious, leading to a global phase out agreement known as the Montreal Protocol.
The phase out of CFCs has been accomplished globally. Even though old systems are still running, no new systems or virgin CFC for service are allowed.
The replacement was to a large extent handled by replacing CFCs with HFCs without compromising safety during installation and use. However, as we know today, the widespread use of HFCs eventually becomes a major global warming source.
R22 is the predominant HCFC due to its wide applicability. R22 is, however, also part of the phase out plans due to its minor ODS potential. Developed countries have already accomplished the phase out of R22, while developing countries are still using R22 as the major refrigerant. Phase out here has already started, and will continue with a 10 % step-down in 2015.
The phase out of R22 in developed countries has raised the question: What is the best substitute? While the developed countries introduced HFC in the 90'es, the developing countries are facing a difficult dilemma. On the one hand they could decide to use new, low GWP solutions which still do not have a high degree of maturity but will fit into the development plans of the markets in the developed countries. Or they could decide to use well proven HFC technologies which, however, may be obsolete in a few years.
Guide with information about retrofit and high glide refrigerants
The Montreal Protocol on Substances that Deplete the Ozone Layer