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US EPA Nonattainment Areas and Designations

Metadata Updated: February 4, 2023

This web service contains the following state level layers:Ozone 8-hr (1997 standard), Ozone 8-hr (2008 standard), Lead (2008 standard), SO2 1-hr (2010 standard), PM2.5 24hr (2006 standard), PM2.5 Annual (1997 standard), PM2.5 Annual (2012 standard), PM10 (1987 standard), and CO (1990 standard). Full FGDC metadata records for each layer may be found by clicking the layer name at the web service endpoint ( and viewing the layer description. These layers identify areas in the U.S. where air pollution levels have not met the National Ambient Air Quality Standards (NAAQS) for criteria air pollutants and have been designated "nonattainment” areas (NAA)". The data are updated weekly from an OAQPS internal database. However, that does not necessarily mean the data have changed. The EPA Office of Air Quality Planning and Standards (OAQPS) has set National Ambient Air Quality Standards for six principal pollutants, which are called "criteria" pollutants. Under provisions of the Clean Air Act, which is intended to improve the quality of the air we breathe, EPA is required to set National Ambient Air Quality Standards for six common air pollutants. These commonly found air pollutants (also known as "criteria pollutants") are found all over the United States. They are particle pollution (often referred to as particulate matter), ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead. For each criteria pollutant, there are specific procedures used for measuring ambient concentrations and for calculating long-term (quarterly or annual) and/or short-term (24-hour) exposure levels. The methods and allowable concentrations vary from one pollutant to another, and within NAAQS revisions for each pollutant. These pollutants can harm your health and the environment, and cause property damage. Of the six pollutants, particle pollution and ground-level ozone are the most widespread health threats. EPA calls these pollutants "criteria" air pollutants because it regulates them by developing human health-based and/or environmentally-based criteria (science-based guidelines) for setting permissible levels. The set of limits based on human health is called primary standards. Another set of limits intended to prevent environmental and property damage is called secondary standards. 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. For further information please refer to: Questions concerning the status of nonattainment areas, their classification and EPA policy should be directed to the appropriate Regional Offices ( EPA Headquarters should be contacted only when the Regional Office is unable to answer a question.

Access & Use Information

License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Date June 18, 2021
Metadata Created Date November 10, 2020
Metadata Updated Date February 4, 2023
Reference Date(s) July 1, 2015 (publication)
Frequency Of Update weekly

Metadata Source

Harvested from Environmental Dataset Gateway FGDC CSDGM

Additional Metadata

Resource Type Dataset
Metadata Date June 18, 2021
Metadata Created Date November 10, 2020
Metadata Updated Date February 4, 2023
Reference Date(s) July 1, 2015 (publication)
Responsible Party U.S. Environmental Protection Agency, Office of Air and Radiation-Office of Air Quality Planning and Standards (Point of Contact)
Contact Email
Guid bc9d3331-0a85-40cd-a412-e9b27d09fe38_source
Access Constraints Use Constraints: None. Please check sources, scale, accuracy, currency and other available information. Please confirm that you are using the most recent copy of both data and metadata. Acknowledgement of the EPA would be appreciated., Access Constraints: None.
Bbox East Long -12.68151645
Bbox North Lat 61.7110157
Bbox South Lat 6.65223303
Bbox West Long -138.21454852
Coupled Resource
Frequency Of Update weekly
Harvest Object Id 417ec3f3-b94c-481d-a914-7fd65bd17eac
Harvest Source Id ec97977e-585c-416a-b4b3-7d656d36891a
Harvest Source Title Environmental Dataset Gateway FGDC CSDGM
Licence Url
Lineage This lineage was generated by the FGDC CSDGM to 19139 transformation
Metadata Language eng; USA
Metadata Type geospatial
Old Spatial {"type": "Polygon", "coordinates": [[[-138.21454852, 6.65223303], [-12.68151645, 6.65223303], [-12.68151645, 61.7110157], [-138.21454852, 61.7110157], [-138.21454852, 6.65223303]]]}
Progress completed
Spatial Data Service Type
Spatial Reference System
Spatial Harvester True

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