Dust Emissions From Urban Roads Using The Ap-42 And Traker Methods: A Case Study

Silt loading (sL) is an important parameter used to calculate fugitive road dust emission inventories and to reflect emission characteristics. The AP-42 method is commonly used to obtain sL values, but is time consuming, unsafe and can only be used on a limited number of roads. We propose a method combining the AP-42 and Testing Reentrained Aerosol Kinetic Emissions from Roads (TRAKER) methods to accurately measure sL values. By analyzing sL values and the emission potentials (theta) of 12 typical urban roads in Baoding, China during spring, we found that the sL values have a strong correlation with theta (Pearson correlation coefficient 0.94; p = 0.01). We investigated the distribution of sL over a large number of urban areas, including 93 urban roads in Baoding, based on the close relationship between sL values and theta. Our results show that the average sL values are influenced by the size of the sampling area-for example, if the AP-42 method is only used to sample a few typical roads, then this might lead to high uncertainties in the emission inventories for road dust. Hence using a rapid detection system and expanding the detection range are both important if we are to acquire more accurate sL values. Our methods and results provide a unique perspective with which to acquire the emission characteristics of road dust.