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, 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 C1051167624257
Rockwall Heath C69176644060
Kaufman C71/A304/X071165634256
Dallas Executive Airport C402175674261
Parker County C76175684362
Granbury C73/C681171664059
Grapevine Fairway C70/A301/X182182713863
Dallas North No.2 C63/C679181734165
Pilot Point C1032174734363
Dallas Hinton St. C401/C60/AH161 380653861
Denton Airport South C56/A163/X157176714263
Ft. Worth Northwest C13/AH302 276674061
Midlothian OFW C52/A137168634057
Frisco C31/C680181764166
Italy C1044/A323169594156
Cleburne Airport C77/C682181734165
Arlington Municipal Airport C61176643759
Keller C17278713862
Greenville C1006/A198173614158
Eagle Mountain Lake C75 175754264
Longview C19/A127/C644268674158
Tyler Airport Relocated C82169674359
Karnack C85/AFHP303161624255
El Paso-Juarez
Ivanhoe C414/F514174704262
El Paso UTEP C12/A125/X151/G125276753963
Socorro Hueco C49/F312170674159
Skyline Park C72177724364
Chamizal C41/AH126 178734465
Ascarate Park SE C37/A332/A172/X159175643859
Waco Mazanec C1037168634257
Temple Georgia C1045169634157
Killeen Skylark Field C1047172674260
Beaumont-Port Arthur
SETRPC 43 Jefferson Co Airport C643172744463
Nederland High School C1035 167634257
SETRPC 40 Sabine Pass C640/C1654171674260
Hamshire C64/C654169654359
West Orange C9/A141273644159
Port Arthur West C28/A128/A228170664259
Beaumont-Downtown C2/A112/C2002 268654358
Audubon C38170634158
Austin Northwest C3/A322272634158
Seabrook Friendship Park C45182644162
Houston Westhollow C410169734261
Hou.DeerPrk2 C35/235/1001/AFH139FP239185764267
Houston North Wayside C405166673455
Houston Monroe C406168713959
Conroe Relocated C78/A321175744364
Houston East C1/G316282704365
Channelview C15/AH115 379673961
Lake Jackson C1016 167634558
Baytown Garth C1017181694163
Park Place C416177723862
Houston Croquet C409270754162
Houston Aldine C8/AF108/X150 288814270
Houston Bayland Park C53/A146 177804667
Clinton C403/C304/AH113 368733859
Northwest Harris Co. C26/A110/X154277734565
Manvel Croix Park C84171794364
Lang C408274754063
Galveston 99th St. C1034/A320/X183176794767
Lynchburg Ferry C1015/A165 174684060
San Antonio
Camp Bullis C58 173694462
Calaveras Lake C59171634660
San Antonio Northwest C23272754363
Corpus Christi-Victoria
Victoria C87166624557
Corpus Christi West C4261624154
Corpus Christi Tuloso C21160584052
Lower Rio Grande Valley
Brownsville C80/AGP1801  *   
Mission C43/AP143159533850
Harlingen Teege C1023159593952
Laredo Vidaurri C44/AFGP144/P244158593952
* 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.