Nonattainment Area - 8 hr ozone (2008) Open Data Catalog

This web service identifies areas in the U.S. where air pollution levels have not met the National Ambient Air Quality Standard to establish the spatial boundaries of each nonattainment and maintenance area. It is intended to help provide the public with information to determine whether or not air quality within a given area is healthy. Once designations take effect, they also become an important component of state, tribal and local governments' efforts to control criteria air pollutants. The Nonattainment Area - 8 hr ozone (2008) 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 areas identified in the U.S. where ground-level ozone have not met the National Ambient Air Quality Standards (NAAQS) established in 2008 for ground-level ozone and have been designated "nonattainment areas (NAA)". These data are weekly from an OAQPS internal database. However, that does not necessarily mean the data have changed. For more information about this non-attainment area, please see the website https://www.epa.gov/green-book/green-book-8-hour-ozone-2008-area-information. A data dictionary, or other source of attribute information, is accessible at https://doi.org/10.21949/1529060