The report gives results of a study to derive size-specific particulate emission factors for industrial paved and unpaved roads and for rural unpaved roads from an existing field testing data base. Regression analysis was used to develop predictive emission factor equations which relate emission quantities to road and traffic parameters. Separate equations were developed for each road type and for three aerodynamic particle size fractions: < or = 15, < or = 10, and < or = 2.5 micrometers. Recommendations are made for including the resulting emission factors in EPA document AP-42. Over the past few years, traffic-generated dust emissions from unpaved and paved industrial roads have become recognized as a significant source of atmospheric particulate emissions, especially within industries involved in mining and processing mineral aggregates. Although a considerable amount of field testing of industrial roads has been performed, most studies have focused on total suspended particulate (TSP) emissions, because the current national ambient air quality standards (NAAQS) for particulate matter are based on TSP. Only recently, in anticipation of a NAAQS for particulate matter based on particle size, has the emphasis shifted to the development of size-specific emission factors.

"October 1985." Includes bibliographical references. Final report. Microfiche. EPA contract no.