CLEAN AIR ACT SUCCESS STORY: CONTINUING REDUCTIONS IN TRANSPORTATION EMISSIONS

The Clean Air Act and related legislation and regulations have played a major role in improving air quality through reduced on-road motor vehicle emissions, despite increases in population and in personal and freight travel. Technological innovations, cleaner fuels, and highway and transit programs have reduced emissions significantly in the past 20 years, and this trend is projected to continue. New measures taking effect in the next few years will intensify the clean air trends. This article looks closely at some of these trends, such as the following: from 1990 to 1999, only 9% of metropolitan areas had an upward trend in 1-hr ozone concentrations, only 1% of metropolitan areas had an upward trend of PM10 (particulate matter 10 micrometers in diameter or smaller) concentrations, and no metropolitan areas had an upward trend of carbon monoxide concentrations.

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    • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
  • Corporate Authors:

    Transportation Research Board

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  • Authors:
    • Jensen, G
  • Publication Date: 2003-7

Language

  • English

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 4-9
  • Serial:
    • TR News
    • Issue Number: 227
    • Publisher: Transportation Research Board
    • ISSN: 0738-6826
  • Publication flags:

    Open Access (libre)

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Filing Info

  • Accession Number: 00962801
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Sep 8 2003 12:00AM