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Ground-level Ozone Pollution

2015 Revision to 2008 Ozone National Ambient Air Quality Standards (NAAQS) Related Documents

On October 1, 2015, EPA strengthened the National Ambient Air Quality Standards (NAAQS) for ground-level ozone to 70 parts per billion (ppb), based on extensive scientific evidence about ozone’s effects on public health and welfare. The updated standards will improve public health protection, particularly for at-risk groups including children, older adults, people of all ages who have lung diseases such as asthma, and people who are active outdoors, especially outdoor workers. They also will improve the health of trees, plants and ecosystems.

This page contains a variety of fact sheets and other documents that are supplementary to the October 2015 revision for the 2008 Ozone National Ambient Air Quality Standards (NAAQS).

See the Federal Register notice for the 2015 Ozone NAAQS 

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