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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 October 2015, 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, 2023, 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
Three-Year
Average
202320242025
as of
8:10 pm CDT
6/30/2025
Dallas-Fort Worth
Corsicana Airport C1051164736768
Rockwall Heath C69167655763
Kaufman C71/A304/X071171726770
Dallas Executive Airport C402179806875
Parker County C76178746472
Granbury C73/C681179766372
Grapevine Fairway C70/A301/X182184816777
Dallas North No.2 C63/C679180806775
Pilot Point C1032181836977
Dallas Hinton St. C401/C60/AH161 3797740 **65
Denton Airport South C56/A163/X157178846174
Ft. Worth Northwest C13/AH302 284856879
Frisco C31/C680182847279
Italy C1044/A323170676467
Cleburne Airport C77/C682175766471
Arlington Municipal Airport C61174806773
Keller C17280886778
Greenville C1006/A198169685865
Eagle Mountain Lake C75 181896578
Tyler-Longview-Marshall
Longview C19/A127/C644267696366
Tyler Airport Relocated C82171676166
Karnack C85/AFHP303165625761
El Paso-Juarez
Ivanhoe C414/F514164655661
Socorro Hueco C49/F312166775967
Ojo De Agua C1021/FG121/FG221174756270
Skyline Park C72168776670
Chamizal C41/AH126 168745766
Ascarate Park SE C37/A332/A172/X159169746268
Waco
Waco Mazanec C1037176716972
Temple Georgia C1045176626668
Killeen Skylark Field C1047176717172
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643166695463
Nederland 17th Street C1035170735766
SETRPC 40 Sabine Pass C640/C1654168705865
Hamshire C64/C654167675763
West Orange C9/A141268675663
Port Arthur West C28/A128/A228163625359
Beaumont-Downtown C2/A112/C2002 268675764
Austin
Audubon C38170686467
Austin North Hills Drive C3/A322274706168
Houston-Galveston-Brazoria
Seabrook Friendship Park C45173805770
Houston Westhollow C410/C3003177786372
Hou.DeerPrk2 C35/235/1001/AFH139/FP239183846276
Houston Harvard Street C417178906477
Houston North Wayside C405/C1033174925573
Houston Monroe C406178665867
Conroe Relocated C78/A321172817877
Houston East C1/G316290846379
Channelview C15/AH115 385756073
Lake Jackson C1016 173706168
Baytown Garth C1017183786575
Park Place C416185826477
Houston Croquet C409280766573
Houston Aldine C8/AF108/X150 278976981
Houston Bayland Park C53/A146 187836578
Clinton C403/C304/AH113 382845774
Northwest Harris Co. C26/A110/X154279827177
Manvel Croix Park C84182726372
Lang C408283836476
Galveston 99th St. C1034/A320/X183181786675
Lynchburg Ferry C1015/A165 182785872
San Antonio
Camp Bullis C58 176737073
Calaveras Lake C59171706568
San Antonio Northwest C23274766070
Corpus Christi-Victoria
Victoria C87159696464
Corpus Christi West C4264655962
Corpus Christi Tuloso C21165636062
Lower Rio Grande Valley
Mission C43/AP143151 *535854
Harlingen Teege C1023160565757
* The value shown for this site does not represent an entire year's worth of data (274 days of valid data).
** The value shown for this site does not represent a complete set of data for 2025 (135 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.