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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
0:11 am CDT
Dallas-Fort Worth
Corsicana Airport C1051165676264
Rockwall Heath C69167766469
Kaufman C71/A304/X071162656363
Dallas Executive Airport C402163756768
Parker County C76165756869
Granbury C73/C681166716667
Grapevine Fairway C70/A301/X182173827175
Dallas North No.2 C63/C679177817377
Pilot Point C1032168747371
Dallas Hinton St. C401/C60/AH161 375806573
Denton Airport South C56/A163/X157173767173
Ft. Worth Northwest C13/AH302 273766772
Midlothian OFW C52/A137167686366
Frisco C31/C680172817676
Italy C1044/A323166695964
Cleburne Airport C77/C682175817376
Arlington Municipal Airport C61171766470
Keller C17275787174
Greenville C1006/A198166736166
Eagle Mountain Lake C75 170757573
Longview C19/A127/C644262686765
Tyler Airport Relocated C82163696766
Karnack C85/AFHP303163616262
El Paso-Juarez
Ivanhoe C414/F514163747069
El Paso UTEP C12/A125/X151/G125274767575
Socorro Hueco C49/F312162706766
Skyline Park C72175777274
Chamizal C41/AH126 172787374
Ascarate Park SE C37/A332/A172/X159167756468
Waco Mazanec C1037164 *686365
Temple Georgia C1045172696368
Killeen Skylark Field C1047168726769
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643164727470
Nederland High School C1035 165676365
SETRPC 40 Sabine Pass C640/C1654167716768
Hamshire C64/C654163696565
West Orange C9/A141261736466
Port Arthur West C28/A128/A228164706666
Beaumont-Downtown C2/A112/C2002 267686566
Audubon C38167706366
Austin Northwest C3/A322270726368
Seabrook Friendship Park C45167826471
Houston Westhollow C410171697371
Hou.DeerPrk2 C35/235/1001/AFH139FP239166857675
Houston North Wayside C405168666767
Houston Monroe C406159687166
Conroe Relocated C78/A321179757476
Houston East C1/G316270827074
Channelview C15/AH115 365796770
Lake Jackson C1016 165676365
Baytown Garth C1017173816974
Park Place C416172777273
Houston Croquet C409267707570
Houston Aldine C8/AF108/X150 274888181
Houston Bayland Park C53/A146 174778077
Clinton C403/C304/AH113 377687372
Northwest Harris Co. C26/A110/X154274777475
Manvel Croix Park C84177717975
Lang C408270747573
Galveston 99th St. C1034/A320/X183173767976
Lynchburg Ferry C1015/A165 146 *746862
San Antonio
Camp Bullis C58 172736971
Calaveras Lake C59165716366
San Antonio Northwest C23273727573
Corpus Christi-Victoria
Victoria C87163666263
Corpus Christi West C4260616261
Corpus Christi Tuloso C21161605859
Lower Rio Grande Valley
Brownsville C80/AGP180158  *  
Mission C43/AP143155595355
Harlingen Teege C1023159595959
Laredo Vidaurri C44/AFGP144/P244153 *585956
* 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.