Quantification of Dust Entrainment from Paved Roadways.

摘要

This report presents the results of a field testing program to develop emission factors for fugitive dust entrainment from paved urban roads. Substantial evidence has been compiled which indicates that dust emissions from city streets are a major cause of nonattainment of national air quality standards for total suspended particulates (TSP). Therefore,the quantification of this source is necessary to the development of effective attainment and maintenance strategies. Field testing was conducted at representative sites in the Kansas City area. At one location,controlled amounts of pulverized top soil and gravel fines were applied to the road surface. The basic measurements consisted of isokinetic exposure and concentration profiles of airborne dust,particle size distributions,dust deposition profiles,surface dust loading,and traffic characteristics. In addition,conventional high-volume samplers were used to determine attenuation of TSP concentration with distance from the source. Emissions are found to vary directly with traffic volume and surface loading of silt (fines). The dust emission factor for normally loaded urban streets ranges from 1to 15 g/vehicle-km,depending on land use. Approximately 90% of the emissions (by weight) is less than 30micrometers in diameter and 50% less than 5micrometers in diameter.