6-4 Index of Key Air Pollutant Emissions from U.S. Transportation: 1990-2007

6-4 Index of Key Air Pollutant Emissions from U.S. Transportation: 1990-2007

Index: 1990 = 1.0

Excel | CSV | Table Version

Figure 6-4 - Index of Key Air Pollutant Emissions from U.S. Transportation: 1990-2007. If you are a user with disability and cannot view this image, use the table version. If you need further assistance, call 800-853-1351.

Key: R = revised, PM-10 = airborne particulates of less than 10 microns, PM-2.5 = airborne particulates of less than 2.5 microns.

Notes: The indexes are calculated using data on emissions from highway vehicles only. Particle matters include PM without condensibles.

Source: U.S. Environmental Protection Agency, Clearinghouse for Inventories and Emissions Factors (CHIEF), Current Emission Trends Summaries, available at http://www.epa.gov/ttn/chief/trends/index.html as of October 2008.