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Compliance with Eight-Hour Ozone Standard

In July 1997, the U. S. Environmental Protection Agency (EPA) announced a new National Ambient Air Quality Standard (NAAQS) for ground-level ozone. The EPA phased out and replaced the previous one-hour standard with an eight-hour standard to protect public health against longer exposure to this air pollutant. In March 2008, the EPA updated the eight-hour standard again. A community will meet the eight-hour standard when the three-year average of the annual fourth highest daily maximum eight-hour ozone concentration measured at each monitoring site is less than 71 parts per billion (ppb).

Highlighted rows show the monitor in each area that may ultimately be used to determine the area's compliance with the ozone standard. These highlighted monitors have measured an area's ozone concentrations over the past three years.

Below are the annual fourth highest daily maximum eight-hour average ozone concentrations from data collected beginning January 1, 2022, to date. Data is updated each hour. Data is given for each area that has ozone monitors.

Use the selection boxes below to customize this report. If you want to cut and paste data from this page into another application, such as a spreadsheet, select the comma-delimited format. Click on the Generate Report button once you have made your selections.

YearReport Format
AreaMonitoring SitePOCFourth Highest AverageCurrent
as of
2:10 am CDT
Dallas-Fort Worth
Corsicana Airport C1051166646163
Rockwall Heath C69162675461
Kaufman C71/A304/X071169716267
Dallas Executive Airport C402177796172
Parker County C76175785469
Granbury C73/C681181796173
Grapevine Fairway C70/A301/X182178845672
Dallas North No.2 C63/C679172806271
Pilot Point C1032177816975
Dallas Hinton St. C401/C60/AH161 363796268
Denton Airport South C56/A163/X157178786373
Ft. Worth Northwest C13/AH302 280845773
Midlothian OFW C52/A137163 *   
Frisco C31/C680173826473
Italy C1044/A323166705563
Cleburne Airport C77/C682182755671
Arlington Municipal Airport C61177745669
Keller C17272806070
Greenville C1006/A198165695663
Eagle Mountain Lake C75 177815872
Longview C19/A127/C644264676063
Tyler Airport Relocated C82171716368
Karnack C85/AFHP303165655561
El Paso-Juarez
Ivanhoe C414/F514164645561
Socorro Hueco C49/F312175666167
Ojo De Agua C1021/FG121/FG221179745970
Skyline Park C72172686468
Chamizal C41/AH126 168686667
Ascarate Park SE C37/A332/A172/X159168695664
Waco Mazanec C1037162766266
Temple Georgia C1045167765766
Killeen Skylark Field C1047169766068
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643165665562
Nederland 17th Street C1035165 *705964
SETRPC 40 Sabine Pass C640/C1654162686063
Hamshire C64/C654162675661
West Orange C9/A141262685762
Port Arthur West C28/A128/A228160635358
Beaumont-Downtown C2/A112/C2002 261686063
Audubon C38166705664
Austin North Hills Drive C3/A322273746269
Seabrook Friendship Park C45159735963
Houston Westhollow C410/C3003173775969
Hou.DeerPrk2 C35/235/1001/AFH139FP239168835970
Houston Harvard Street C417178785971
Houston North Wayside C405/C1033162746266
Houston Monroe C406160785564
Conroe Relocated C78/A321173727272
Houston East C1/G316273906174
Channelview C15/AH115 363855668
Lake Jackson C1016 169735666
Baytown Garth C1017171836071
Park Place C416172856373
Houston Croquet C409272805669
Houston Aldine C8/AF108/X150 264786870
Houston Bayland Park C53/A146 184876277
Clinton C403/C304/AH113 376825571
Northwest Harris Co. C26/A110/X154274796773
Manvel Croix Park C84172826071
Lang C408271835971
Galveston 99th St. C1034/A320/X183173816472
Lynchburg Ferry C1015/A165 163825767
San Antonio
Camp Bullis C58 175766271
Calaveras Lake C59170715866
San Antonio Northwest C23276746070
Corpus Christi-Victoria
Victoria C87160595658
Corpus Christi West C4262645660
Corpus Christi Tuloso C21157655559
Lower Rio Grande Valley
Mission C43/AP14316351 *5155
Harlingen Teege C1023157605557
* The value shown for this site does not represent an entire year's worth of data (274 days of valid data).

PLEASE NOTE:  This data has not been verified by the TCEQ and may change. This is the most current data, but it is not official until it has been certified by our technical staff. Data is collected from TCEQ ambient monitoring sites and may include data collected by other outside agencies. This data is updated hourly. All times shown are in local standard time unless otherwise indicated.

Following EPA reporting guidelines, negative values may be displayed in our hourly criteria air quality data, down to the negative of the EPA listed Method Detection Limit (MDL) for the particular instrument that made the measurements. The reported concentrations can be negative due to zero drift in the electronic instrument output, data logger channel, or calibration adjustments to the data. Prior to 1/1/2013, slightly negative values were automatically set to zero.