Exposure to Carbon Monoxide
Managing Carbon Monoxide Pollution in Meteorological and Topographical Problem Areas
. The report concluded: “CO control has been one of the greatest success stories in air-pollution control. As a result, the focus of United States air quality management has shifted to characterizing and controlling other pollutants, such as tropospheric ozone, fine particulate matter (PM
), and air toxics.” (NRC 2003, p. 149) As evidence for this conclusion, the NRC acknowledged that the number of monitoring stations showing violations of the National Ambient Air Quality Standards (NAAQS) for CO had fallen significantly from the early 1970s when CO monitoring became widespread. Many of the remaining violations occur in areas with meteorological or topographical handicaps. For example, CO violations in Fairbanks, Alaska, have been attributed to stagnant air masses during winter. The atmosphere is more likely to be stable during winter, because there is less solar heating and more frequent ground-level temperature inversions. Other contributing factors are low wind speeds and mountains that hinder dispersion of air pollutants. However, violations are occurring less frequently even in areas with these natural handicaps (NRC 2003).