In the 1970s, scientists first grew concerned that certain chemicals could damage the Earth's protective ozone layer. In the early 1980s, these concerns were validated by the discovery that the ozone layer in the stratosphere over Antarctica was thinning. While the ozone did not completely disappear in this area, it was so thin that scientists and the popular press started talking about an "ozone hole" .
A compromised ozone layer - and the resulting increase in ultraviolet (UV) radiation hitting the Earth's surface - can have serious consequences. Overexposure to UV radiation in humans can cause a range of health and environmental effects, including skin damage (skin cancers and premature aging), eye damage (including cataracts), and suppression of the immune system. Scientific studies also suggest a link between ultraviolet radiation and adverse effects on some animal and plant life and some plastic materials.
Because of the risks posed by ozone depletion, leaders from many countries decided to craft a workable solution. Since 1987, 191 nations - almost every country in the world - have ratified a landmark environmental treaty, the Montreal Protocol on Substances that Deplete the Ozone Layer. The Protocol's chief aim is to reduce and eventually eliminate the production and use of man-made ozone depleting substances (ODS). By agreeing to the terms of the Montreal Protocol, signatory nations - including the United States - committed to take actions to protect the ozone layer, hoping in the long-term to reverse the damage that had been done by the use of ozone depleting substances.
Why does the U.S. need regulations to protect the ozone layer?
As part of the United States' commitment to implementing the Montreal Protocol, the U.S. Congress amended America's Clean Air Act, adding provisions (under Title VI) for protection of the ozone layer. Most importantly, the amended Act required the gradual end to the production of chemicals that deplete the ozone layer.
The U.S. federal agency primarily responsible for the management of air quality and atmospheric protection issues is the U.S. Environmental Protection Agency. The Clean Air Act amendments passed by Congress require that EPA develop and implement regulations for the responsible management of ozone-depleting substances in the United States.
Under the Clean Air Act, EPA has created several regulatory programs to address numerous issues, including:
- ending the production of ozone-depleting substances
- ensuring that refrigerants and halon fire extinguishing agents are recycled properly
- identifying safe and effective alternatives to ozone-depleting substances
- banning the release of ozone-depleting refrigerants during the service, maintenance, and disposal of air conditioners and other refrigeration equipment
- requiring that manufacturers label products either containing or made with the most harmful ODS.
With input from industry groups, environmentalists, and the public, EPA has published a range of regulations for the protection of the ozone layer. Because of their relatively high ozone depletion potential, several man-made compounds including chlorofluorocarbons (CFCs), chlorofluorocarbons (HCFCs), carbon tetrachloride, methyl chloroform, methyl bromide, and halons were targeted for phaseout. EPA is developing additional regulations under its ozone protection program for the continued protection of the environment and public health.
EPA is also charged with enforcement of these regulations. Enforcement actions, which are handled through headquarters and at the local level primarily through EPA's ten regional offices, range from civil fines to criminal prosecutions. To date, several people have been imprisoned for breaking ozone protection laws, and many more have been fined.
Besides implementing and enforcing ozone-protecting regulations in the U.S., EPA continues to work with other U.S. government agencies, including the State Department, Department of Justice, Department of Homeland Security (including Customs and Border Protection and Immigration and Customs Enforcement), U.S. Department of Agriculture, as well as with international governments to pursue ongoing amendments to the Montreal Protocol and other treaties. These refinements to the Protocol and other treaties are based on ongoing scientific assessments of ozone depletion which are coordinated by the United Nations Environment Programme and the World Meteorological Organization, with cooperation from EPA and other agencies around the globe.
To help protect the American public from the health effects of overexposure to UV radiation, EPA maintains several education and outreach projects. The UV Index, which EPA launched in partnership with the National Weather Service, provides a daily forecast of the next day's likely UV levels across the United States. The UV Index serves as a key piece of EPA's SunWise School Program. The goal of the SunWise program is to educate young children and their caregivers about the health effects of overexposure to the sun, as well as simple steps that people can take to avoid overexposure. This is done through a number of classroom, school, and community based components.
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