Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and halons destroy the earth's protective ozone layer, which shields the earth from harmful ultraviolet (UV-B) rays generated from the sun. CFCs and HCFCs also warm the lower atmosphere of the earth, changing global climate. Hydrofluorocarbons (HFCs) also act to warm the planet. The Minnesota Pollution Control Agency (MPCA) is working with industry, residents and government to reduce the damage done to the ozone layer and global climate by CFCs, HCFCs, HFCs and related chemicals.
Man-made compounds such as chlorofluorocarbons (CFCs), hydrofluorocarbons (HCFCs) and halons destroy ozone in the upper atmosphere (stratosphere). The stratospheric ozone layer makes life possible by shielding the earth from harmful ultraviolet (UV-B) rays generated from the sun. Decreased concentration of stratospheric ozone allows increased amounts of UV-B to reach the earth's surface.
Stratospheric ozone loss can result in potential harm to human health and the environment, including:
- increased incidence of skin cancer and cataracts
- immune system system damage
- damage to terrestrial and aquatic plant life
- increased formation of ground-level ozone (smog)
Most stratospheric ozone depletion is caused when chlorine or bromine reacts with ozone. Most of the chlorine entering the stratosphere is from man-made sources (84%), such as CFCs and HCFCs with the remaining 16% from natural sources, such as the ocean and volcanoes. About half of bromine entering the stratosphere is from man-made sources, mostly Halons.
While acting to destroy ozone, CFCs and HCFCs also act to trap heat in the lower atmosphere, causing the earth to warm and climate and weather to change. HFCs, which originally were developed to replace CFCs and HCFCs, also absorb and trap infrared radiation or heat in the lower atmosphere of the earth. HFCs, CFCs and HFCs are a subset of a larger group of climate changing gases called greenhouse gases (GHGs). Taken together greenhouse gases are expected to warm the planet by 2.5 to 8 degrees Fahrenheit by the end of century.
HFCs, CFCs and HFCs contribute an estimated 11.5% to present-day effect of GHGs on climate and climate change. Some effects of global climate change include:
- Rising sea levels
- Local natural species extinctions and habitat loss
- More frequent heavy rainfall and flooding
- High heat stress in summer
- Increasing health risk from insect and water-borne diseases
The production of CFCs in the United Stated or their import was prohibited as of January 1, 1996. Use of CFCs is restricted to equipment placed into use prior to 1996. The production or import of HCFC-22 and HCFC-142b for use in new units or applications was banned in the US as of January 1, 2010, although production and import for use in existing equipment is allowed through 2019. The production or import of HCFC-141b for any purpose were prohibited as of January 1, 2004.
Most HFC uses in new units or applications are being phased out under USEPA Rules over a staggered schedule that begins in 2016 and stretches through 2024. Under these Rules, most HFC uses in polyurethane and other foams and in new retail food refrigerated cases will be phased out between January 1, 2016 and January 1 2020. Use of HFCs in mobile air conditioning will end with Model Year 2020, while prohibitions on HFC use in new fire suppression systems, cold storage, residential refrigeration, and building chillers go into place on January 1 of 2018, 2021, 2023 and 2024, respectively.
Use of HFCs in existing equipment is unaffected by EPA regulations. Minnesota has an estimated 12 million residential appliances and car air conditioners that contain a total of about 13,000 tons of CFCs, HCFCs and HFCs.
Regulations are in place to help prevent the release of CFCs, HCFCs and HFCs into the environment. In addition to the various production bans, servicers and disposers of appliances and motor vehicle air conditioners are required to obtain technician certification, proper refrigerant recovery or recycling equipment, and keep records.
- Climate change in Minnesota
- Report Environmental Violations (US EPA) – Lodge a complaint related to CFCs or other ozone-depleting substances
- Significant New Alternatives Policy (US EPA) – Information on recent EPA rulemakings on HFC and HCFC production and use prohibitions
- 2014 Scientific Assessment of Ozone Depletion (World Meteorological Organization) – The science of ozone depletion
- Fifth Assessment Report (Intergovernmental Panel on Climate Changes) – Global warming and greenhouse gases
- Technical information for handling refrigerants – Businesses that service, dispose of, and recycle appliances and vehicle air conditioners