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Dallas-Fort Worth: Current Attainment Status

Compliance of Dallas-Fort Worth (DFW) area counties with the National Ambient Air Quality Standards (NAAQS).

DFW Area: Attainment Status by Pollutant

Note: This table is intended to provide a listing of designations and classifications for current, active National Ambient Air Quality Standards (NAAQS). While NAAQS which have been revoked by the EPA do not appear in this table, some antibacksliding obligations may continue to apply for revoked standards. This table is to be used for informational purposes only and should not be used to determine regulatory requirements in any of the counties listed.




Primary NAAQS


Averaging Period






Attainment Deadline


Ozone (O3)*

0.070 ppm (2015 standard) 





0.075 ppm (2008 standard)


Moderate Nonattainment

Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant, Wise

July 20, 2018

Lead (Pb)

0.15 µg/m3
(2008 standard)

Rolling 3-Month Average


Portion of Collin

December 31, 2015

1.5 µg/m3
(1978 standard)

Quarterly Average

Attainment (Maintenance)

Portion of Collin


Carbon Monoxide (CO)

9 ppm


Unclassifiable/ Attainment



35 ppm


Unclassifiable/ Attainment



Nitrogen Dioxide (NO2)

0.053 ppm


Unclassifiable/ Attainment



100 ppb


Unclassifiable/ Attainment



Particulate Matter (PM10)

150 µg/m3


Unclassifiable/ Attainment



Particulate Matter (PM2.5)

12.0 µg/m3 (2012 standard)

Annual (Arithmetic Mean)

Unclassifiable/ Attainment



15.0 µg/m3 (1997 standard)

Annual (Arithmetic Mean)

Unclassifiable/ Attainment



35 µg/m3


Unclassifiable/ Attainment



Sulfur Dioxide (SO2)

0.03 ppm**

Annual (Arithmetic Mean)

Unclassifiable/ Attainment



0.14 ppm**


Unclassifiable/ Attainment



75 ppb


Governor's Recommendation: Attainment

Dallas, Ellis, Kaufman, Navarro


  *The United States Environmental Protection Agency (EPA) revoked the one-hour ozone standard and the 1997 eight-hour ozone standard in all areas, although some areas have continuing obligations under these standards. See ozone history for more information.

**The standard is scheduled to be revoked one year after the effective date of final designations for the 75 ppb standard.

For more information on attainment status, visit the EPA's Green Book Exit the TCEQ Web page regarding nonattainment areas for criteria pollutants.

DFW Nonattainment Areas

2008 Eight-Hour Ozone Standard Designations: Moderate Nonattainment, effective July 20, 2012 (77 FR 30088) Exit the TCEQ
On March 27, 2008, the EPA lowered the primary and secondary eight-hour ozone NAAQS to 0.075 parts per million (73 FR 16436) Exit the TCEQ. A ten-county DFW area including Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant, and Wise Counties was designated nonattainment and classified moderate under the 2008 eight-hour ozone NAAQS, effective July 20, 2012. The DFW area includes the nine counties that were designated nonattainment under the 1997 eight-hour ozone standard in addition to Wise County. The attainment deadline for the DFW moderate nonattainment area is July 20, 2018.

1997 Eight-Hour Ozone Standard Designations: Serious Nonattainment, effective January 19, 2011 (75 FR 79302) Exit the TCEQ
A nine-county DFW area was originally designated a moderate nonattainment area under the 1997 eight-hour ozone NAAQS and was subsequently reclassified as a serious nonattainment area in 2011. Counties included are Dallas, Denton, Collin, Ellis, Johnson, Kaufman, Parker, Rockwall, and Tarrant.
Status: Based on data from 2012 through 2014, the DFW area is monitoring attainment of the 1997 eight-hour ozone NAAQS. On February 27, 2015, the TCEQ submitted a request for a finding that the DFW area is attaining the 1997 eight-hour ozone NAAQS. On September 1, 2015, the EPA finalized a clean data determination for the DFW 1997 eight-hour ozone nonattainment area (80 FR 52630) Exit the TCEQ.

2008 Lead Standard Designation: Nonattainment, effective December 31, 2010 (75 FR 71033) Exit the TCEQ
In the November 22, 2010, Federal Register, the EPA published a determination that an area in Collin County, Texas surrounding Exide Technologies battery recycling plant was not meeting the 2008 lead standard. On August 8, 2012, the commission adopted the Collin County Attainment Demonstration SIP Revision for the 2008 Lead NAAQS and the Agreed Order between Exide and the TCEQ. The Collin County lead nonattainment area must attain the 2008 lead standard by December 31, 2015.
Status: The Colin County area achieved compliance of the 2008 lead NAAQS as of December 31, 2015. The TCEQ is developing a SIP revision to request that the EPA redesignate the Frisco lead nonattainment area to attainment based on 36 months of monitoring data below the federal standard. For additional information, please visit the Dallas-Fort Worth: Lead - Latest Planning Activities Web page.

1978 Lead Standard Designation: Attainment, October 13, 1999 (64 FR 55421) Exit the TCEQ
All Texas counties are currently in attainment of the EPA’s 1978 lead standard. Collin County was designated attainment in 1999. A second 10-year maintenance plan for Collin County was adopted by the TCEQ on August 26, 2009, and has been submitted to the EPA for review.

National Ambient Air Quality Standards

The EPA has set National Ambient Air Quality Standards Exit the TCEQ (NAAQS) for six principal criteria pollutants: ground-level ozone, lead, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter.

No later than one year after promulgation of a new or revised NAAQS for any pollutant, the governor must submit designation recommendations to the EPA for all areas of the state. The EPA must then promulgate the designations within two years of promulgation of the revised NAAQS. Areas that do not meet (or contribute to ambient air quality in a nearby area that does not meet) the NAAQS are designated nonattainment. Areas that meet the NAAQS are designated attainment; and areas that cannot be classified based on the available information, unclassifiable.

For ozone, the Federal Clean Air Act establishes nonattainment area classifications ranked according to the severity of the area’s air pollution problem. These classifications—marginal, moderate, serious, severe, and extreme—translate to varying requirements with which Texas and nonattainment areas must comply.