Skip to main content

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, 2017, 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
12:10 pm CDT
Dallas-Fort Worth
Corsicana Airport C1051165674057
Rockwall Heath C69167763960
Kaufman C71/A304/X071162654156
Dallas Executive Airport C402163753959
Parker County C76165754260
Granbury C73/C681166714059
Grapevine Fairway C70/A301/X182173823864
Dallas North No.2 C63/C679177813865
Pilot Point C1032168743960
Dallas Hinton St. C401/C60/AH161 375803764
Denton Airport South C56/A163/X157173763862
Ft. Worth Northwest C13/AH302 273763561
Midlothian OFW C52/A137167683857
Frisco C31/C680172813863
Italy C1044/A323166694058
Cleburne Airport C77/C682175814065
Arlington Municipal Airport C61171763861
Keller C17275783863
Greenville C1006/A198166733959
Eagle Mountain Lake C75 170754162
Longview C19/A127/C644262684056
Tyler Airport Relocated C82163694659
Karnack C85/AFHP303163613954
El Paso-Juarez
Ivanhoe C414/F514163744761
El Paso UTEP C12/A125/X151/G125274765267
Socorro Hueco C49/F312162704659
Skyline Park C72175774866
Chamizal C41/AH126 172784966
Ascarate Park SE C37/A332/A172/X159167754562
Waco Mazanec C1037164 *683856
Temple Georgia C1045172694060
Killeen Skylark Field C1047168724361
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643164724660
Nederland High School C1035 165674258
SETRPC 40 Sabine Pass C640/C1654167714661
Hamshire C64/C654163694659
West Orange C9/A141261734660
Port Arthur West C28/A128/A228164704258
Beaumont-Downtown C2/A112/C2002 267684459
Audubon C38167704059
Austin Northwest C3/A322270724161
Seabrook Friendship Park C45167824163
Houston Westhollow C410171694361
Hou.DeerPrk2 C35/235/1001/AFH139FP239166854465
Houston North Wayside C405168663155
Houston Monroe C406159683554
Conroe Relocated C78/A321179754666
Houston East C1/G316270824164
Channelview C15/AH115 365793660
Lake Jackson C1016 165674559
Baytown Garth C1017173814365
Park Place C416172773962
Houston Croquet C409267704259
Houston Aldine C8/AF108/X150 274884669
Houston Bayland Park C53/A146 174773762
Clinton C403/C304/AH113 377683660
Northwest Harris Co. C26/A110/X154274774465
Manvel Croix Park C84177714464
Lang C408270743860
Galveston 99th St. C1034/A320/X183173764665
Lynchburg Ferry C1015/A165 146 *743752
San Antonio
Camp Bullis C58 172734362
Calaveras Lake C59165714560
San Antonio Northwest C23273724362
Corpus Christi-Victoria
Victoria C87163664156
Corpus Christi West C4260614455
Corpus Christi Tuloso C21161603953
Lower Rio Grande Valley
Brownsville C80/AGP180158  *  
Mission C43/AP143155593850
Harlingen Teege C1023159594353
Laredo Vidaurri C44/AFGP144/P244153 *584451
* 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.