Access the latest NEI data set. Under 'Sector Summaries - Criteria and Hazardous Air Pollutants by 60 EIS emission sectors', > choose National > for Pollutant, choose PM10 Primary and/ or PM2.5-PRI > Sector, choose all sectors >Submit Query to see results at bottom of page. Open the results in Excel, and then calculate the national sum of pollutant emissions and the percent contribution to total by the 'dust' sectors, i.e., dust from activities on unpaved road, paved road, construction, and agriculture crops and livestock. Please see attached file for result. The PM10 is a coarser fraction of particulate matter than the PM2.5 (fine) and, so represents a larger portion of the particulate from dust activities. The estimation method is described in the technical support document. For example, pg 4-73 for unpaved road dust PM emissions. Browse the TSD table of contents for other fugitive dust emission categories.