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Air Trends

Particulate Matter

National Trends in Particulate Matter Levels
Regional Trends in Particulate Matter Levels
Local Trends in Particulate Matter Levels

National Trends in Particulate Matter Levels

Using a nationwide network of monitoring sites, EPA has developed ambient air quality trends for particle pollution, also called Particulate Matter (PM). Under the Clean Air Act, EPA sets and reviews national air quality standards for PM. Air quality monitors measure concentrations of PM throughout the country. EPA, state, tribal and local agencies use that data to ensure that PM in the air is at levels that protect public health and the environment. Nationally, average PM concentrations have decreased over the years. For information on PM standards, sources, health effects, and programs to reduce PM, please see www.epa.gov/airquality/particlepollution.

PM2.5 air quality between 2000 and 2012, based on the seasonally-weighted annual average.  Chart shows a range of concentrations in 570 monitoring sites nationwide, with the average decreasing 33% from 2000 to 2012.

How to Interpret the Graphs
View the chart data in Microsoft Excel  (Download Excel Viewer) Exit EPA Disclaimer
View the chart data in HTML  (New window opens)


PM10 air quality between 1990 and 2012, based on the seasonally-weighted annual average.  Chart shows a range of concentrations in 239 monitoring sites nationwide, with the average decreasing 39% from 1990 to 2012.

How to Interpret the Graphs
View the chart data in Microsoft Excel  (Download Excel Viewer) Exit EPA Disclaimer
View the chart data in HTML  (New window opens)


PM10 air quality between 2000 and 2012, based on the seasonally-weighted annual average.  Chart shows a range of concentrations in 511 monitoring sites nationwide, with the average decreasing 27% from 2000 to 2012.

How to Interpret the Graphs
View the chart data in Microsoft Excel  (Download Excel Viewer) Exit EPA Disclaimer
View the chart data in HTML  (New window opens)


Regional Trends in Particulate Matter Levels

Air quality trends can vary regionally. The following climatically consistent regions within the contiguous United States provide a relevant way to look at regional trends in air quality. [Need to work on this text.]


Source: NOAA National Climatic Data Center

Local Trends in Particulate Matter LevelsNote to users of screen readers:  The Local Trends information is available on the web only as graphical images.  Please call 919-541-5224 for assistance.

Air quality trends can vary from one area to another. Local trends can be viewed at individual monitoring locations in the maps below or in this PM10 KML file (KML, 1 MB) or this PM2.5 KML file (KML, 546 KB) using Google Earth or another KML browser. 

 PM10 monitors that meet mimimum trends completeness criteria
 PM10 monitors that have some data during the trend period but do not meet the mimimum trends completeness criteria



 PM2.5 monitors that meet mimimum trends completeness criteria
 PM2.5 monitors that have some data during the trend period but do not meet the mimimum trends completeness criteria

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