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Sulfur Dioxide (SO2) Pollution

Fact Sheets and Additional Information Regarding the Primary National Ambient Air Quality Standard (NAAQS) for Sulfur Dioxide

This page contains a fact sheet on the 2019 decision to retain the existing standard, as well as fact sheets and other documents related to the setting of the existing standard in 2010.  This page also contains a pre-publication version of the final decision. 

For more information, visit the SO2 NAAQS page.

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