USDOT_BTS_NTAD_Nonattainment_8_hr_Ozone_1997 eng; USA utf8 dataset Halil Cakir Environmental Protection Agency (EPA) Environmental Scientist 919-541-5390 109 T.W. Alexander Drive Research Triangle Park NC 27709 US Cakir.Halil@epa.gov pointOfContact 2026-07-24 ISO 19139 Geographic Information - Metadata ISO/TS 19139:2007 solid 136 3857 EPSG Nonattainment Area - 8 hr Ozone (1997 Standard) 2004-07-01 creation 2026-07-18 publication 2026-07-18 revision Environmental Protection Agency (EPA) originator vector The Nonattainment Area - 8 hr Ozone (1997) dataset was updated on June 30, 2026 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 1997 for ground-level ozone and have been designated "nonattainment areas (NAA)". This dataset also shows the nonattainment areas at the time of the 8-Hour Ozone (1997) National Ambient Air Quality Standards (NAAQS) revocation on April 6, 2015. 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-1997-area-information-naaqs-revoked. A data dictionary, or other source of attribute information, is accessible at https://doi.org/10.21949/1529059 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. Acknowledgment of the U.S. Environmental Protection Agency's Office of Air Quality Planning and Standards (OAQPS), Air Quality Policy Division, and the Bureau of Transportation Statistics (BTS) [distributor]. onGoing Halil Cakir Environmental Protection Agency (EPA) Environmental Scientist 919-541-5390 109 T.W. Alexander Drive Research Triangle Park NC 27709 US Cakir.Halil@epa.gov pointOfContact weekly NTAD National Transportation Atlas Database National Transportation Atlas Database vector polygon Environment Environmental Planning Boundary Non Attainment Nonattainment Area NAA EPA NAAQS Air Air Quality OAR-OAQPS Designations Standards Pollutant Pollutants Criteria Pollutants 8 hour 8 hr Ozone 8 hr Ozone 1997 theme none USA National place none This NTAD dataset is a work of the United States government as defined in 17 U.S.C. § 101 and as such are not protected by any U.S. copyrights. This work is available for unrestricted public use. otherRestrictions Access Constraints: unrestricted National Transportation Atlas Database 2026-07-18 publication Bureau of Transportation Statistics (BTS) publisher largerWorkCitation vector eng; USA environment Native Dataset Environment: Version 6.2 (Build 9200) ; Esri ArcGIS 10.8.1.14362 -123.107877731 -67.9432999999999 28.8242230000001 45.4285540000001 2026-06-30 0 Nonattainment Area - 8 hr Ozone (1997) A data dictionary resource of attribute information is accessible at https://doi.org/10.21949/1529059 Bureau of Transportation Statistics (BTS) NTAD Program Manager 1200 New Jersey Ave. SE Washington DC 20590 United States ntad@dot.gov distributor None. No fees are applicable for obtaining the dataset. https://doi.org/10.21949/1522185 http Open Data Catalog Web page to view and download dataset. The file download formats available include: ESRI File Geodatabase or Shapefile, GeoPackage, Comma-Seperated Values (CSV), Microsoft Excel, GeoJSON, KML, Feature Collection, and SQLite Geodatabase. download https://doi.org/10.21949/1522187 http ArcGIS REST Services Directory Feature Server (WFS) complies with OGC WFS Map Service for visualizing geospatial information download https://doi.org/10.21949/1520833 http Repository and Open Science Access Portal (ROSA P) NTAD Archive Collection ZIP download dataset Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. A geographic area that meets or does better than the primary standard is called an attainment area; areas that don't meet the primary standard are called nonattainment areas. In some cases, a designated nonattainment area can include portions of 2, 3, or 4 states rather than falling entirely within a single state. Multi-state areas have had different state portions handled through up to 3 separate EPA regional offices. The actions of EPA and the state governments for separate portions of such areas are not always simultaneous. While some areas have had coordinated action from all related states on the same day, other areas (so-called "split areas") have had delays of several months, ranging up to more than 2 years, between different states. EPA must designate areas as meeting (attainment) or not meeting (nonattainment) the standard. A designation is the term EPA uses to describe the air quality in a given area for any of the six common air pollutants (criteria pollutants). After EPA establishes or revises a primary and/or secondary National Ambient Air Quality Standard (NAAQS), the Clean Air Act requires EPA to designate areas as “attainment” (meeting), “nonattainment” (not meeting), or “unclassifiable” (insufficient data) after monitoring data is collected by state, local and tribal governments. Once nonattainment designations take effect, the state and local governments have three years to develop implementation plans outlining how areas will attain and maintain the standards by reducing air pollutant emissions. asNeeded Halil Cakir Environmental Protection Agency (EPA) Environmental Scientist 919-541-5390 109 T.W. Alexander Drive Research Triangle Park NC 27709 United States Cakir.Halil@epa.gov custodian