Published in 1980
This report describes a method for estimating the probability that a highway facility will violate the eight hour National Ambient Air Quality Standard (NAAQS) for carbon monoxide (CO). The method is predicated on the assumption that overlapping eight-hour time periods which each yield average CO levels in excess of the NAAQS specified maximum level are counted as single rather than multiple pollution episodes. Air pollution levels are largely subject to the random influences of wind speed, wind direction, and atmospheric turbulence. Thus, with respect to an air quality standard, the acceptability of a proposed facility cannot be established deterministically. Since pollution levels seem best modeled as random variables, it is natural to address potential air quality impacts by estimating the probability of violating the relevant air quality standards.
Last updated: January 24, 2024