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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
4:10 pm CDT
Dallas-Fort Worth
Corsicana Airport C1051167626364
Rockwall Heath C69176646468
Kaufman C71/A304/X071165636564
Dallas Executive Airport C4021756764 **68
Parker County C76175686368
Granbury C73/C681171666266
Grapevine Fairway C70/A301/X182182717174
Dallas North No.2 C63/C679181736874
Pilot Point C1032174736871
Dallas Hinton St. C401/C60/AH161 380656369
Denton Airport South C56/A163/X157176716972
Ft. Worth Northwest C13/AH302 276676870
Midlothian OFW C52/A137168636063
Frisco C31/C680181766574
Italy C1044/A323169596062
Cleburne Airport C77/C682181736874
Arlington Municipal Airport C611766464 **68
Keller C17278716370
Greenville C1006/A198173616165
Eagle Mountain Lake C75 175757073
Longview C19/A127/C644268675563
Tyler Airport Relocated C82169676065
Karnack C85/AFHP303161625559
El Paso-Juarez
Ivanhoe C414/F514174706469
El Paso UTEP C12/A125/X151/G125276756973
Socorro Hueco C49/F312170676366
Skyline Park C72177726671
Chamizal C41/AH126 178736471
Ascarate Park SE C37/A332/A172/X159175646367
Waco Mazanec C1037168636264
Temple Georgia C1045169636064
Killeen Skylark Field C1047172676066
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643172745868
Nederland High School C1035 167635662
SETRPC 40 Sabine Pass C640/C1654171675965
Hamshire C64/C654169655864
West Orange C9/A141273645965
Port Arthur West C28/A128/A228170665764
Beaumont-Downtown C2/A112/C2002 268655863
Audubon C38170636164
Austin Northwest C3/A3222726341 **58
Seabrook Friendship Park C45182645767
Houston Westhollow C410169736167
Hou.DeerPrk2 C35/235/1001/AFH139FP239185766274
Houston North Wayside C405166675863
Houston Monroe C406168715564
Conroe Relocated C78/A321175746972
Houston East C1/G316282706271
Channelview C15/AH115 379675767
Lake Jackson C1016 167636364
Baytown Garth C1017181696270
Park Place C416177725668
Houston Croquet C409270756068
Houston Aldine C8/AF108/X150 288816477
Houston Bayland Park C53/A146 177806574
Clinton C403/C304/AH113 368735966
Northwest Harris Co. C26/A110/X154277737073
Manvel Croix Park C84171796571
Lang C408274756671
Galveston 99th St. C1034/A320/X183176796272
Lynchburg Ferry C1015/A165 174685565
San Antonio
Camp Bullis C58 173697070
Calaveras Lake C59171636365
San Antonio Northwest C23272756570
Corpus Christi-Victoria
Victoria C87166626062
Corpus Christi West C4261625860
Corpus Christi Tuloso C21160586460
Lower Rio Grande Valley
Brownsville C80/AGP1801  *   
Mission C43/AP143159535555
Harlingen Teege C1023159595056
Laredo Vidaurri C44/AFGP144/P244158595958
* 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 (139 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.