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Nitrogen Dioxide (NO2) Pollution

Fact Sheets: Ambient Nitrogen Dioxide Monitoring Requirements

EPA removed the requirement to install near-road nitrogen dioxide (NO₂) monitoring stations in Core Based Statistical Areas (CBSAs) having populations between 500,000 and 1 million. Under the original monitoring requirements, these monitors were due to be installed and operational by January 1, 2017.

This page includes fact sheets related to the proposed and final action.

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Proposed NO2 Monitoring Revisions Fact Sheet (PDF)(3 pp, 51 K)
Final NO2 Monitoring Revisions Fact Sheet (PDF)(2 pp, 42 K, 12/22/2016)