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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, 2018, 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
1:11 am CDT
Dallas-Fort Worth
Corsicana Airport C1051167626364
Rockwall Heath C69176646468
Kaufman C71/A304/X071165636564
Dallas Executive Airport C402175676769
Parker County C76175686870
Granbury C73/C681171666266
Grapevine Fairway C70/A301/X182182717776
Dallas North No.2 C63/C679181736974
Pilot Point C1032174737172
Dallas Hinton St. C401/C60/AH161 380656469
Denton Airport South C56/A163/X157176717172
Ft. Worth Northwest C13/AH302 276677572
Midlothian OFW C52/A137168636164
Frisco C31/C680181767075
Italy C1044/A323169596062
Cleburne Airport C77/C682181736773
Arlington Municipal Airport C61176646869
Keller C17278717173
Greenville C1006/A198173616165
Eagle Mountain Lake C75 175757675
Longview C19/A127/C644268675563
Tyler Airport Relocated C82169676065
Karnack C85/AFHP303161625559
El Paso-Juarez
Ivanhoe C414/F514174706870
El Paso UTEP C12/A125/X151/G125276757976
Socorro Hueco C49/F312170677470
Skyline Park C72177727173
Chamizal C41/AH126 178737274
Ascarate Park SE C37/A332/A172/X159175646969
Waco Mazanec C1037168636364
Temple Georgia C1045169636465
Killeen Skylark Field C1047172676367
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643172746068
Nederland High School C1035 167635762
SETRPC 40 Sabine Pass C640/C1654171676266
Hamshire C64/C654169656265
West Orange C9/A141273646266
Port Arthur West C28/A128/A228170665764
Beaumont-Downtown C2/A112/C2002 268655964
Audubon C38170636365
Austin North Hills Drive C3/A3222726346 **60
Seabrook Friendship Park C45182646470
Houston Westhollow C410169736669
Hou.DeerPrk2 C35/235/1001/AFH139FP239185767378
Houston North Wayside C405166676164
Houston Monroe C406168716267
Conroe Relocated C78/A321175747574
Houston East C1/G316282706773
Channelview C15/AH115 379676269
Lake Jackson C1016 167636565
Baytown Garth C1017181696672
Park Place C416177727073
Houston Croquet C409270756670
Houston Aldine C8/AF108/X150 288816879
Houston Bayland Park C53/A146 177807376
Clinton C403/C304/AH113 368737170
Northwest Harris Co. C26/A110/X154277737173
Manvel Croix Park C84171797073
Lang C408274756972
Galveston 99th St. C1034/A320/X183176796874
Lynchburg Ferry C1015/A165 174686167
San Antonio
Camp Bullis C58 173697472
Calaveras Lake C59171636666
San Antonio Northwest C23272756972
Corpus Christi-Victoria
Victoria C87166626062
Corpus Christi West C4261626161
Corpus Christi Tuloso C21160586460
Lower Rio Grande Valley
Brownsville C80/AGP1801  *   
Mission C43/AP143159535555
Harlingen Teege C1023159595357
Laredo Vidaurri C44/AFGP144/P244158596059
* 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 2020 (248 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.