Air Quality Strategies:
Protecting the Ozone Layer

The ozone layer, which exists within the stratosphere, between 10 and 40 kilometers above the earth's surface, shields the earth's surface from excess ultraviolet radiation. If ozone concentrations were to drop significantly, the resulting increases in the ultraviolet radiation that passes through the atmosphere would dramatically increase the rate of skin cancer and could cause dramatic environmental changes. 

Chlorofluorocarbons (CFCs) are the principal ozone-depleting gas, but methyl chloride, methane gas, and halons also can break down stratospheric ozone. CFCs were widely used in solvents and a refrigerants, but their use has been phased out over the last decade.  

The 1987 Montreal Protocol called for a 50% reduction in the use of ozone-depleting chemicals by the year 2000. This World Bank website provides information and updates on the agreement.

The EPA' s Ozone Depletion website provides background information about ozone depletion, information about the regulatory approach to protecting the ozone layer, and information on alternatives to ozone-depleting substances, for businesses that use or manufacture ozone-depleting substances. In addition, EPA provides Ozone Depletion Rules & Regulations from the Clean Air Act and elsewhere.

GNET, the Global Network of Environment and Technology, has a TechKnow section that includes the Ozone Protection Technologies Information Clearinghouse System (OPTICS), a listing of technologies that manage, destroy, characterize or recycle ozone depleting substances.

OzonAction Programme of the United Nations Environment Programme Division of Technology, Industry and Economics offers information on regulation, compliance, and how companies can help protect the ozone layer, as well as a directory of information resources on the Internet related to the phase out of ozone depleting substances.

NASA's Earth Observatory website includes a section on ozone and ozone layer monitoring.

On-line Articles and Publications  

Frequently Asked Questions about Ozone Depletion and the Ozone Hole, from the Union of Concerned Scientists.

The Ozone Layer, from the European Commission, includes information on what individuals can do to help protect the ozone layer.

Chlorofluorocarbons and Ozone Depletion, a thematic guide from the Center for International Earth Science Information Network.

Ozone Depletion Chapter 2 of The World Environment 1972-1992. New York: Chapman and Hall. 

Ozone Depletion and Global Environmental Change, a thematic guide from the Center for International Earth Science Information Network.

Frequently Asked Questions about Stratospheric Ozone Depletion, from the United Nations Environmental Programme.

Stratospheric Ozone Information from the EPA Technology Transfer Network OAR Policy and Guidance.


Last updated: January 31, 2005

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