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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, 2015, 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
9:11 pm CST
Dallas-Fort Worth
Corsicana Airport C1051164606563
Rockwall Heath C69171616465
Kaufman C71/A304/X071164576160
Dallas Executive Airport C402168626364
Parker County C76179686570
Granbury C73/C681173636667
Grapevine Fairway C70/A301/X182179757175
Dallas North No.2 C63/C679179677272
Pilot Point C1032179756773
Dallas Hinton St. C401/C60/AH161 380696972
Denton Airport South C56/A163/X157188767278
Ft. Worth Northwest C13/AH302 279667272
Midlothian OFW C52/A137168606564
Frisco C31/C680177737173
Italy C1044/A323166606363
Cleburne Airport C77/C682173727573
Arlington Municipal Airport C61169616966
Keller C17276707272
Greenville C1006/A198162586662
Eagle Mountain Lake C75 178676971
Longview C19/A127/C644268656265
Tyler Airport Relocated C82166636364
Karnack C85/AFHP303162596261
El Paso-Juarez
Ivanhoe C414165596362
El Paso UTEP C12/A125/X151272717472
Socorro Hueco C49/F312169646164
Skyline Park C72169666667
Chamizal C41/AH126 170657168
Ascarate Park SE C37/A332/A172/X159164666665
Waco Mazanec C1037168606464
Temple Georgia C1045172647068
Killeen Skylark Field C1047167666867
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643165596462
Nederland High School C1035 174636567
SETRPC 40 Sabine Pass C640/C1654164676665
Hamshire C64/C654168696266
West Orange C9/A141262586160
Port Arthur West C28/A128/A228175646467
Beaumont-Downtown C2/A112/C2002 269606564
Audubon C38173626667
Austin Northwest C3/A322273646968
Seabrook Friendship Park C45183646671
Houston Westhollow C410179796173
Hou.DeerPrk2 C35/235/1001/AFH139FP239177626467
Houston North Wayside C405178626468
Houston Monroe C406173575662
Conroe Relocated C78/A321173717773
Houston East C1/G316288676774
Channelview C15/AH115 381616468
Lake Jackson C1016 165666565
Baytown Garth C1017177656870
Park Place C416187656171
Houston Croquet C409279676269
Houston Aldine C8/AF108/X150 295747079
Houston Texas Avenue C411 (Deactivated Oct 24, 2016)18570  
Houston Bayland Park C53/A146 180786373
Clinton C403/C304/AH113 384656370
Northwest Harris Co. C26/A110/X154278677071
Manvel Croix Park C84186697075
Lang C408291696374
Galveston 99th St. C1034/A320/X183184747377
Lynchburg Ferry C1015/A165 1795942 **60
San Antonio
Camp Bullis C58 180697273
Calaveras Lake C59168626464
San Antonio Northwest C23279717374
Corpus Christi-Victoria
Victoria C87170646265
Corpus Christi West C4265626062
Corpus Christi Tuloso C21162616061
Lower Rio Grande Valley
Brownsville C80/AGP180160525656
Mission C43/AP143158525555
Harlingen Teege C1023158555957
Laredo Vidaurri C44/AFGP144/P244156505353
** The value shown for this site does not represent a complete set of data for 2017 (173 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.