Nonattainment Area - 1 hr Ozone (1979 Standard-Revoked)

The Nonattainment Area - 1 hr Ozone (1979) dataset was updated on June 30, 2025 by the Environmental Protection Agency (EPA) and is part of the U.S. Department of Transportation (USDOT)/Bureau of Transportation Statistics (BTS) National Transportation Atlas Database (NTAD). This dataset provides detailed information about designations, classifications and the status of the nonattainment areas at the time of the 1-Hour Ozone (1979) National Ambient Air Quality Standards (NAAQS) revocation. On June 15, 2005 the 1-Hour Ozone NAAQS was revoked for all areas except the 8-Hour Ozone nonattainment Early Action Compact (EAC) areas. These data are updated weekly from an OAQPS internal database. However, that does not necessarily mean the data have changed. For more information about this nonattainment area, please see the website https://www.epa.gov/green-book/green-book-1-hour-ozone-1979-area-information-naaqs-revoked. A data dictionary, or other source of attribute information, is accessible at https://doi.org/10.21949/1529058