Chlorofluorocarbons (CFCs) are halocarbons and the most well known ozone-depleting substances (ODS). CFCs are a family of long-lasting synthetic chemicals that were developed about 60 years ago as a substitute for ammonia in refrigerators and air conditioners. They have also been used as blowing agents in foam product manufacturing, as cleaning solvents for electrical components, in aerosol sprays, and in hospital sterilization procedures.
Production of CFCs has ceased in all countries and current uses are being controlled and phased out because of their impact on the ozone layer.
Hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs) are alternative halocarbons being used to replace ODS in industrial and commercial applications and their use is becoming more widespread. Other alternatives to ODS include ammonia, carbon dioxide and hydrocarbons.
Ozone-depleting substances (ODS) and their halocarbon alternatives have a direct global warming potential and contribute to climate change. The production of some ozone depleting substances (e.g. CFCs) has been ceased worldwide resulting in emission reductions of ozone-depleting substances into the atmosphere. However, emissions of other ODS (e.g. hydrochlorofluorocarbons [HCFCs]) and ODS alternatives (e.g. hydrofluorocarbons [HFCs]) is expected to continue to increase.
HFCs are ODS refrigerants alternatives and their use is becoming more widespread. Although HFCs have no ozone-depletion potential they do have high global-warming potential and are thousands of times more potent greenhouse gases than carbon dioxide.
Regulations that prevent or minimize ODS and other halocarbons emissions serve a dual environmental benefit of lowering emissions that destroy the ozone layer and contribute to climate change.
Although the production and use of many ODS has been phased out, the control of ODS emissions continues to be an important environmental issue, as the destruction of the earth’s protective stratospheric ozone layer causes increased health risks and environmental impacts, such as cataracts, skin cancer and climate change.