Managing Carbon Monoxide Pollution in Meteorological and Topographical Problem Areas

This executive summary is provided by the National Academies as part of their mission to educate the world on issues of science, engineering, and health. The regulation of carbon monoxide has been one of the great success stories in air pollution control. While more than 90 percent of the locations with carbon monoxide monitors were in violation in 1971, today the number of monitors showing violations has fallen to only a few, on a small number of days and mainly in areas with unique meteorological and topographical conditions. The publication describes how a primary objective of air quality management in the United States has been to reduce human exposure to carbon monoxide (CO) and other pollutants produced from incomplete combustion. Elevated ambient CO concentrations are due mainly to incomplete combustion of gasoline by light-duty vehicles, such as passenger cars and pickup trucks. CO controls are working. Problems with ambient CO were widespread when automobile emissions regulations began in the 1960s. When the health-based National Ambient Air Quality Standards (NAAQS) for CO were promulgated in 1971, more than 90% of ambient monitors indicated violations. Since then, motor-vehicle emissions controls have greatly reduced ambient CO concentrations. Over the last 5 years, the number of monitors showing CO violations has fallen to only a few, and the monitors that continue to show violations do so much less frequently. For example, Denver, Colorado, which had a persistent CO problem and registered as many as 200 days with violations in the 1960s, has not had a violation since 1995. Fairbanks, Alaska, reduced the number of days with violations from well over 100 per year in the early 1970s to zero over the last 2 years. Thus, CO regulation has been one of the greatest success stories in air pollution control, reducing the problem, once widespread, to a few difficult areas. As a result, the focus of U.S. air quality management has shifted to characterizing and controlling other pollutants, such as tropospheric ozone, fine particulate matter (PM2.5), and air toxics.


  • English

Media Info

  • Media Type: Print
  • Features: Appendices; Figures; Maps; References; Tables;
  • Pagination: 196p

Subject/Index Terms

Filing Info

  • Accession Number: 01139817
  • Record Type: Publication
  • ISBN: 9780309089234
  • Files: TRIS
  • Created Date: Sep 15 2009 4:58PM