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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
2:10 am CDT
Dallas-Fort Worth
Corsicana Airport C1051167624457
Rockwall Heath C69176644662
Kaufman C71/A304/X071165634758
Dallas Executive Airport C402175674763
Parker County C76175684863
Granbury C73/C681171664460
Grapevine Fairway C70/A301/X182182714566
Dallas North No.2 C63/C679181734767
Pilot Point C1032174734463
Dallas Hinton St. C401/C60/AH161 380654463
Denton Airport South C56/A163/X157176714664
Ft. Worth Northwest C13/AH302 276674261
Midlothian OFW C52/A137168635361
Frisco C31/C680181764667
Italy C1044/A323169594557
Cleburne Airport C77/C682181734666
Arlington Municipal Airport C61176644862
Keller C17278714464
Greenville C1006/A198173614660
Eagle Mountain Lake C75 175754765
Longview C19/A127/C644268674359
Tyler Airport Relocated C82169674761
Karnack C85/AFHP303161624756
El Paso-Juarez
Ivanhoe C414/F514174705064
El Paso UTEP C12/A125/X151/G125276754966
Socorro Hueco C49/F312170675062
Skyline Park C72177725166
Chamizal C41/AH126 178735568
Ascarate Park SE C37/A332/A172/X159175644461
Waco Mazanec C1037168634759
Temple Georgia C1045169634759
Killeen Skylark Field C1047172674862
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643172745165
Nederland High School C1035 167634759
SETRPC 40 Sabine Pass C640/C1654171674862
Hamshire C64/C654169654961
West Orange C9/A141273644661
Port Arthur West C28/A128/A228170664761
Beaumont-Downtown C2/A112/C2002 268654960
Audubon C38170634860
Austin Northwest C3/A3222726341 **58
Seabrook Friendship Park C45182644463
Houston Westhollow C410169734763
Hou.DeerPrk2 C35/235/1001/AFH139FP239185764869
Houston North Wayside C405166674057
Houston Monroe C406168714561
Conroe Relocated C78/A321175744865
Houston East C1/G316282704666
Channelview C15/AH115 379674664
Lake Jackson C1016 167635361
Baytown Garth C1017181694866
Park Place C416177724564
Houston Croquet C409270754663
Houston Aldine C8/AF108/X150 288814972
Houston Bayland Park C53/A146 177805169
Clinton C403/C304/AH113 368734461
Northwest Harris Co. C26/A110/X154277734765
Manvel Croix Park C84171795066
Lang C408274754765
Galveston 99th St. C1034/A320/X183176795269
Lynchburg Ferry C1015/A165 174684361
San Antonio
Camp Bullis C58 173695164
Calaveras Lake C59171634961
San Antonio Northwest C23272754965
Corpus Christi-Victoria
Victoria C87166625159
Corpus Christi West C4261624756
Corpus Christi Tuloso C21160585056
Lower Rio Grande Valley
Brownsville C80/AGP1801  *   
Mission C43/AP143159534351
Harlingen Teege C1023159594454
Laredo Vidaurri C44/AFGP144/P244158594754
* 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 (68 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.