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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, 2017, 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
7:10 pm CDT
Dallas-Fort Worth
Corsicana Airport C1051165676264
Rockwall Heath C69167765867
Kaufman C71/A304/X071162656363
Dallas Executive Airport C402163756567
Parker County C76165756267
Granbury C73/C681166716266
Grapevine Fairway C70/A301/X182173826071
Dallas North No.2 C63/C679177816674
Pilot Point C1032168747070
Dallas Hinton St. C401/C60/AH161 375806172
Denton Airport South C56/A163/X157173766571
Ft. Worth Northwest C13/AH302 273766069
Midlothian OFW C52/A137167686366
Frisco C31/C680172817174
Italy C1044/A323166696065
Cleburne Airport C77/C682175817276
Arlington Municipal Airport C61171766069
Keller C17275786171
Greenville C1006/A198166736066
Eagle Mountain Lake C75 170756670
Longview C19/A127/C644262686364
Tyler Airport Relocated C82163696565
Karnack C85/AFHP303163616061
El Paso-Juarez
Ivanhoe C414/F514163746366
El Paso UTEP C12/A125/X151/G125274766270
Socorro Hueco C49/F312162706164
Skyline Park C72175776472
Chamizal C41/AH126 172786270
Ascarate Park SE C37/A332/A172/X159167755967
Waco Mazanec C1037164 *685963
Temple Georgia C1045172696368
Killeen Skylark Field C1047168726769
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643164726868
Nederland High School C1035 165676064
SETRPC 40 Sabine Pass C640/C1654167716768
Hamshire C64/C654163696465
West Orange C9/A141261736365
Port Arthur West C28/A128/A228164706466
Beaumont-Downtown C2/A112/C2002 267686466
Audubon C38167706266
Austin Northwest C3/A322270726268
Seabrook Friendship Park C45167826370
Houston Westhollow C410171697070
Hou.DeerPrk2 C35/235/1001/AFH139FP239166857374
Houston North Wayside C405168666265
Houston Monroe C406159686764
Conroe Relocated C78/A321179757476
Houston East C1/G316270826773
Channelview C15/AH115 365797071
Lake Jackson C1016 165676264
Baytown Garth C1017173816874
Park Place C416172777273
Houston Croquet C409267707069
Houston Aldine C8/AF108/X150 274887378
Houston Bayland Park C53/A146 174778077
Clinton C403/C304/AH113 377686269
Northwest Harris Co. C26/A110/X154274776772
Manvel Croix Park C84177717574
Lang C408270746569
Galveston 99th St. C1034/A320/X183173767374
Lynchburg Ferry C1015/A165 146 *746662
San Antonio
Camp Bullis C58 172736369
Calaveras Lake C59165716165
San Antonio Northwest C23273726068
Corpus Christi-Victoria
Victoria C87163665962
Corpus Christi West C4260616261
Corpus Christi Tuloso C21161605157
Lower Rio Grande Valley
Brownsville C80/AGP180158  *  
Mission C43/AP143155595155
Harlingen Teege C1023159595959
Laredo Vidaurri C44/AFGP144/P244153 *585254
* The value shown for this site does not represent an entire year's worth of data (274 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.