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Airborne Particulates

Particle pollution (also called particulate matter or PM) is the term for a mixture of solid particles and liquid droplets found in the air. Some particles, such as dust, dirt, soot, or smoke, are large or dark enough to be seen with the naked eye. Others are so small, they can only be detected using an electron microscope. Particle pollution includes inhalable coarse particles, with diameters larger than 2.5 micrometers and smaller than 10 micrometers and fine particles, with diameters that are 2.5 micrometers and smaller. How small is 2.5 micrometers? Think about a single hair from your head. The average human hair is about 70 micrometers in diameter -- making it 30 times larger than the largest fine particle. These particles come in many sizes and shapes and can be made up of hundreds of different chemicals. Some particles, known as primary particles, are emitted directly from a source, such as construction sites, unpaved roads, fields, smokestacks or fires. Others form in complicated reactions in the atmosphere of chemicals such as sulfur dioxides and nitrogen oxides that are emitted from power plants, industries and automobiles. These particles, known as secondary particles, make up most of the fine particle pollution in the country.

This information is updated hourly. All times shown are Local Standard Time.

Click here for a map showing the current PM-2.5 (Local Conditions) levels.

Click here for a map showing the current PM-2.5 (Local Conditions) Acceptable levels.

Click here for a map showing the current PM-10 (Standard Conditions) levels.

Click here for the current Air Quality Index.

PM-2.5 (Local Conditions)

Fine particulates (PM-2.5) are generally emitted from activities such as industrial and residential combustion and from vehicle exhaust. Fine particles are also formed in the atmosphere when gases such as sulfur dioxide, nitrogen oxides, and volatile organic compounds, emitted by combustion activities, are transformed by chemical reactions in the air. Large-scale agricultural burning or sand storms can produce huge volumes of fine particulates. PM-2.5 data is the near real-time measurement of particulate matter 2.5 microns or less in size from the surrounding air. This measurement is made at local conditions, and is not corrected for temperature or pressure.

The table below contains hourly averages for PM-2.5 (Local Conditions) on Thursday, September 20, 2018.

JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember   12345678910111213141516171819202122232425262728293031   19961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018   
Select a Region: All Active Regions Region 1 -- Amarillo Region 2 -- Lubbock Region 3 -- Abilene Region 4 -- DFW Region 5 -- Tyler Region 6 -- El Paso Region 7 -- Midland Region 8 -- San Angelo Region 9 -- Waco Region 10 -- Beaumont Region 11 -- Austin Region 12 -- Houston Region 13 -- San Antonio Region 14 -- Corpus Christi Region 15 -- Harlingen Region 16 -- Laredo Region 20 -- PM-2.5 Speciation Region 88 -- TCEQ Mobile Monitoring

There is no PM-2.5 (Local Conditions) measured in the region you selected.

PM-2.5 (Local Conditions) Acceptable

Fine particulates (PM-2.5) are generally emitted from activities such as industrial and residential combustion and from vehicle exhaust. Fine particles are also formed in the atmosphere when gases such as sulfur dioxide, nitrogen oxides, and volatile organic compounds, emitted by combustion activities, are transformed by chemical reactions in the air. Large-scale agricultural burning or sand storms can produce huge volumes of fine particulates. PM-2.5 data is the near real-time measurement of particulate matter 2.5 microns or less in size from the surrounding air. This measurement is made at local conditions, and is not corrected for temperature or pressure.

The table below contains hourly averages for PM-2.5 (Local Conditions) Acceptable on Thursday, September 20, 2018.

JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember   12345678910111213141516171819202122232425262728293031   19961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018   
Select a Region: All Active Regions Region 1 -- Amarillo Region 2 -- Lubbock Region 3 -- Abilene Region 4 -- DFW Region 5 -- Tyler Region 6 -- El Paso Region 7 -- Midland Region 8 -- San Angelo Region 9 -- Waco Region 10 -- Beaumont Region 11 -- Austin Region 12 -- Houston Region 13 -- San Antonio Region 14 -- Corpus Christi Region 15 -- Harlingen Region 16 -- Laredo Region 20 -- PM-2.5 Speciation Region 88 -- TCEQ Mobile Monitoring

There is no PM-2.5 (Local Conditions) Acceptable measured in the region you selected.

PM-10 (Standard Conditions)

Coarse particulates (PM-10) come from sources such as windblown dust from the desert or agricultural fields (sand storms) and dust kicked up on unpaved roads by vehicle traffic. PM-10 data is the near real-time measurement of particulate matter 10 microns or less in size from the surrounding air. This measurement is made at standard conditions, meaning it is corrected for local temperature and pressure.

The table below contains hourly averages for PM-10 (Standard Conditions) on Thursday, September 20, 2018.

JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember   12345678910111213141516171819202122232425262728293031   19961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018   
Select a Region: All Active Regions Region 1 -- Amarillo Region 2 -- Lubbock Region 3 -- Abilene Region 4 -- DFW Region 5 -- Tyler Region 6 -- El Paso Region 7 -- Midland Region 8 -- San Angelo Region 9 -- Waco Region 10 -- Beaumont Region 11 -- Austin Region 12 -- Houston Region 13 -- San Antonio Region 14 -- Corpus Christi Region 15 -- Harlingen Region 16 -- Laredo Region 20 -- PM-2.5 Speciation Region 88 -- TCEQ Mobile Monitoring

There is no PM-10 (Standard Conditions) measured in the region you selected.

There were no sites monitoring any parameters for the region you selected.

Try selecting a different date, a different Region, or All Regions.

JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember   12345678910111213141516171819202122232425262728293031   19961997199819992000200120022003200420052006200720082009201020112012201320142015201620172018   
Select a Region: All Active Regions Region 1 -- Amarillo Region 2 -- Lubbock Region 3 -- Abilene Region 4 -- DFW Region 5 -- Tyler Region 6 -- El Paso Region 7 -- Midland Region 8 -- San Angelo Region 9 -- Waco Region 10 -- Beaumont Region 11 -- Austin Region 12 -- Houston Region 13 -- San Antonio Region 14 -- Corpus Christi Region 15 -- Harlingen Region 16 -- Laredo Region 20 -- PM-2.5 Speciation Region 88 -- TCEQ Mobile Monitoring

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.