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
4:10 am CDT
Dallas-Fort Worth
Corsicana Airport C1051165675863
Rockwall Heath C69167765666
Kaufman C71/A304/X071162655861
Dallas Executive Airport C402163755865
Parker County C76165756167
Granbury C73/C681166716065
Grapevine Fairway C70/A301/X182173825770
Dallas North No.2 C63/C679177815972
Pilot Point C1032168746468
Dallas Hinton St. C401/C60/AH161 375805770
Denton Airport South C56/A163/X157173765869
Ft. Worth Northwest C13/AH302 273765467
Midlothian OFW C52/A137167685764
Frisco C31/C680172816071
Italy C1044/A323166695964
Cleburne Airport C77/C682175816172
Arlington Municipal Airport C61171765567
Keller C17275785569
Greenville C1006/A198166735665
Eagle Mountain Lake C75 170756168
Longview C19/A127/C644262685963
Tyler Airport Relocated C82163696264
Karnack C85/AFHP303163615660
El Paso-Juarez
Ivanhoe C414/F514163745564
El Paso UTEP C12/A125/X151/G125274765468
Socorro Hueco C49/F312162705763
Skyline Park C72175775970
Chamizal C41/AH126 172785869
Ascarate Park SE C37/A332/A172/X159167754863
Waco Mazanec C1037164 *685763
Temple Georgia C1045172696067
Killeen Skylark Field C1047168726568
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643164726667
Nederland High School C1035 165675963
SETRPC 40 Sabine Pass C640/C1654167716467
Hamshire C64/C654163696365
West Orange C9/A141261736365
Port Arthur West C28/A128/A228164706165
Beaumont-Downtown C2/A112/C2002 267686165
Audubon C38167706065
Austin Northwest C3/A322270726167
Seabrook Friendship Park C45167826069
Houston Westhollow C410171696167
Hou.DeerPrk2 C35/235/1001/AFH139FP239166856471
Houston North Wayside C405168665763
Houston Monroe C406159685059
Conroe Relocated C78/A321179757074
Houston East C1/G316270826070
Channelview C15/AH115 365796469
Lake Jackson C1016 165676164
Baytown Garth C1017173816573
Park Place C416172775869
Houston Croquet C409267705865
Houston Aldine C8/AF108/X150 274887177
Houston Bayland Park C53/A146 174776070
Clinton C403/C304/AH113 377685767
Northwest Harris Co. C26/A110/X154274776271
Manvel Croix Park C84177716671
Lang C408270746168
Galveston 99th St. C1034/A320/X183173766270
Lynchburg Ferry C1015/A165 146 *745959
San Antonio
Camp Bullis C58 172735968
Calaveras Lake C59165715864
San Antonio Northwest C23273725968
Corpus Christi-Victoria
Victoria C87163665762
Corpus Christi West C4260615659
Corpus Christi Tuloso C21161605157
Lower Rio Grande Valley
Brownsville C80/AGP180158  *  
Mission C43/AP143155595054
Harlingen Teege C1023159595858
Laredo Vidaurri C44/AFGP144/P244153 *585254
* 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.