Currently, the EPA has law suits pending against industrial plants, and private business owners who are in direct violation of the Clean Air Act. Enforcement actions, including fines, and jail sentencing for violators have started to impede the production of CFC's and other ozone depleting substances such as some chromium compounds. Industry has responded to EPA regulations with evasive opposition, and have endeavored to avoid prosecution by falsifying information on federal documents that are issued to curtail the ozone problem.

   The task of replacing CFCs is far from over: even though substitutes have been found for use in a variety of applications, many of these substitutes have problems of their own, and a black market dealing in CFCs has developed. What follows is a brief list of several areas of ongoing research into alternatives to CFC use.

   One of the most promising substitutes for CFCs is HFC-134a. Since HFCs lack chlorine, they cannot participate in the reactions by which CFCs harm the ozone layer. The U.S. Navy has made considerable progress in utilizing this substance as a replacement for CFC cooling systems on many of its ships. [For a video on this topic, click here.] However, HFC-134a comes with a number of engineering problems: conventional lubricating oils are not soluble in it, requiring the development of alternate lubricants or non-lubricated mechanisms¹. It is also a potential contributor to global warming, so it can only be considered "environmentally friendly" if industry can make sure that it is not lost from the devices in which it is used².

   The use of environmentally-friendly substances unrelated to CFCs is undergoing intense research³. Helium, nitrogen, and even ambient air are being tested in prototype cooling systems based on the Stirling Cycle, in which pistons alternately compress and expand the gas being used. Zeolites, which adsorb water vapor when cool and expel it when heated, are being used in solar-powered refrigerators and gas-powered air conditioners. Future developments and price decreases of superconducting magnets may allow the magnetocaloric principle (the heating of certain types of metals when exposed to superconducting magnets, and their cooling when the magnets are removed) to be used in large-scale refrigeration applications.

   An especially notable development is the "Greenfreeze" refrigerator, which was developed by the East German company DKK Scharfenstein (now called Foron) in order to compete with West German refrigerator manufacturers after Germany's unification. Instead of CFCs or HFCs, isobutane or a mixture of isobutane and propane is used. While it is true that, unlike CFCs, these are flammable gases, this has been take into account in the refrigerator's design, and the amount of hydrocarbons used is only about twice that found in a cigarette lighter. This design is coming into widespread use in Europe.

The development of environmentally-friendly CFC alternatives has branched off in many directions and has yielded many promising new technologies. But consumers must keep applying pressure so that the chemical industry is both economically as well as ethically inclined to make the investments of time and money necessary for change.