Skip to main content

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, 2019, 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 C1051162636764
Rockwall Heath C69164646363
Kaufman C71/A304/X071163656363
Dallas Executive Airport C402167677068
Parker County C76168686767
Granbury C73/C681166626564
Grapevine Fairway C70/A301/X182171777574
Dallas North No.2 C63/C679173697371
Pilot Point C1032173718576
Dallas Hinton St. C401/C60/AH161 365647467
Denton Airport South C56/A163/X157171718174
Ft. Worth Northwest C13/AH302 267757672
Midlothian OFW C52/A137163616462
Frisco C31/C680176708175
Italy C1044/A323159606461
Cleburne Airport C77/C682173677571
Arlington Municipal Airport C61164687167
Keller C17271717472
Greenville C1006/A198161616562
Eagle Mountain Lake C75 175767675
Longview C19/A127/C644267556462
Tyler Airport Relocated C82167606564
Karnack C85/AFHP303162556159
El Paso-Juarez
Ivanhoe C414/F514170686467
El Paso UTEP C12/A125/X151/G125275797375
Socorro Hueco C49/F312167747170
Ojo De Agua C1021/FG121/FG2211  71 
Skyline Park C72172716870
Chamizal C41/AH126 173726971
Ascarate Park SE C37/A332/A172/X159164695663
Waco Mazanec C1037163636764
Temple Georgia C1045163646764
Killeen Skylark Field C1047167637066
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643174606666
Nederland High School C1035 163576461
SETRPC 40 Sabine Pass C640/C1654167626063
Hamshire C64/C654165626263
West Orange C9/A141264626162
Port Arthur West C28/A128/A228166576562
Beaumont-Downtown C2/A112/C2002 265596563
Audubon C38163636563
Austin North Hills Drive C3/A32226346 *6658
Seabrook Friendship Park C45164646062
Houston Westhollow C410/C3003173667170
Hou.DeerPrk2 C35/235/1001/AFH139FP239176737474
Houston Harvard Street C4171  79 
Houston North Wayside C405/C1033167616564
Houston Monroe C406171626867
Conroe Relocated C78/A321174757073
Houston East C1/G316270677671
Channelview C15/AH115 367626865
Lake Jackson C1016 163656965
Baytown Garth C1017169667168
Park Place C416172707873
Houston Croquet C409275668374
Houston Aldine C8/AF108/X150 281687574
Houston Bayland Park C53/A146 180737877
Clinton C403/C304/AH113 373717071
Northwest Harris Co. C26/A110/X154273716971
Manvel Croix Park C84179707775
Lang C408275697171
Galveston 99th St. C1034/A320/X183179686972
Lynchburg Ferry C1015/A165 168616564
San Antonio
Camp Bullis C58 169747873
Calaveras Lake C59163666665
San Antonio Northwest C23275697071
Corpus Christi-Victoria
Victoria C87162606161
Corpus Christi West C4262616562
Corpus Christi Tuloso C21158646462
Lower Rio Grande Valley
Mission C43/AP143153556256
Harlingen Teege C1023159535656
Laredo Vidaurri C44/AFGP144/P244 (Deactivated Jul 28, 2021)1596060 **59
* 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 2021 (221 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.