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Air Quality and Monitoring

Featuring the latest information regarding the Texas air monitoring network, monitoring data, and air quality forecast conditions for Texas' metropolitan areas.

Hurricane Update Due to the impending threat of forecasted hurricane force conditions, TCEQ-owned air monitoring sites in the Corpus Christi area have been temporarily shut down. Please  view the status of our sites for more information.

Ambient Air Monitoring

The Federal Clean Air Act provides for establishing national ambient air quality standards (NAAQS) for six commonly occurring air pollutants, or “criteria pollutants”, that can be harmful to public health and the environment.

The TCEQ monitors ambient air concentrations of these and other pollutants at stationary monitoring sites across the state. Near real-time monitoring data can be found using the links in the right and left menus.

The TCEQ also maintains the Texas Air Monitoring Information System (TAMIS) that allows users to generate and download ambient air quality data collected at these monitoring stations.

In addition to the six criteria pollutants, the TCEQ’s monitoring network also measures a variety of air toxics that include hydrogen sulfide, volatile organic compounds, metals, carbonyls, and semi-volatile organic compounds. The specific pollutants measured at each monitoring station can be identified using the GeoTAM viewer.

Placement of air monitors is determined consistent with federal air monitoring rules using population trends, reported emissions inventory data, local meteorological data, and, if available, existing air monitoring data for a given area. In addition, the TCEQ may prioritize monitor placement in areas with potential air quality issues, or to address local air quality concerns. The TCEQ strives to strategically balance meeting federal monitoring requirements and state and local needs with available funding and staffing resources.

Each specific monitor location must meet strict siting criteria that include minimum spacing from trees or other obstructions, free of influences from specific sources, and logistical considerations, such as available space, power, and level terrain. Final site selection is contingent on the TCEQ receiving proper access authorization from property owners for properties that meet these siting criteria.

The TCEQ uses a variety of measures to ensure its air monitoring data is of the utmost quality. Air monitors are assessed daily to verify their operations remain within proper specifications. TCEQ personnel physically visit each monitoring station on a weekly basis to conduct various quality control checks and preventive maintenance activities. The monitoring instruments themselves must meet rigorous sampling and analytical requirements prescribed by federal air monitoring rules and undergo daily, weekly, and quarterly quality control checks to verify the instrument’s calibration, accuracy, and precision. In addition, independently calibrated instruments are used to perform quarterly and annual audits of the air monitors and their operation.

Finally, a validation assessment is performed on all data to verify the TCEQ’s data quality objectives are met. The data are reviewed for outliers, regional comparability, quality assurance/quality control requirements, and other data quality assessment indicators. Data that do not meet these objectives completely are invalidated or denoted accordingly.

The TCEQ air monitoring network is designed to measure pollutant concentrations for assessing regional air quality representative of areas frequented by the public. Monitors can measure the impact on air quality from industrial sources present in an area, but do not measure the emissions from individual sources or determine a source’s compliance with permitted emission limits. Data from the ambient air monitoring network is used to determine compliance with the national ambient air quality standards (NAAQS), evaluate pollutant trends, forecast daily air quality conditions, perform air quality and human health impact studies, and inform regulatory decisions. Finally, while stationary air monitors may provide useful data during disasters or emergency events, they are not specifically intended for those purposes.

Important:
Timeline for Near Real-time Ambient Air Quality Data: The time it takes for near real-time monitoring data to reach our webpages. TCEQ strives to bring you the latest monitoring information data as quickly as possible, The data that we collect is displayed in local standard time (LST) as per EPA standards.

Get e-mail or text updates on your choice of topics Air Quality Forecast and Ozone Action Day E-Mail Alerts (sign up to receive email alerts for several metropolitan areas throughout Texas)

Related Content

Modeling and Studies

For questions about the following studies, please contact the Air Quality Division.

Air Pollutant Watch List and Toxicology

The APWL includes cities or counties that have elevated concentrations of air pollutants. The TCEQ’s Toxicology program oversees the APWL.