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Air Emissions Factors and Quantification

AP 42 Section 13.2.2 Unpaved Roads - Related Information

Paved Roads, Unpaved Roads, Aggregate Handling and Storage, and Industrial Wind Erosion - November 2006

  • Analysis of the Fine Fraction of Particulate Matter in Fugitive Dust. (PDF) (54 pp, 1 MB) Final Report for Western Governors' Association Western Regional Air Partnership (WRAP). October 12, 2005. Posted as supporting documentation for the draft AP42 sections 13.2.1 Paved Roads, 13.2.2 Unpaved Roads, 13.2.4 Aggregate Handling and Storage Piles, and 13.2.5 Industrial Wind Erosion. March 22, 2006.
  • MS Excel spreadsheets that show all of the data for the wind tunnel tests that support the proposed PM2.5/PM-10 ratios.
  • This MS Excel spreadsheet contains a list of Surface Material Silt Content by state. EPA has used these values in the preparation of the National Emission Inventory. In the absence of locally derived surface material silt content, users may choose to use the values in this table as default values.
  • This MS Excel spreadsheet program is for calculating emissions factors which are temporally and spatially resolved. Information required for use of the spreadsheet program includes monthly Class A pan evaporation values, hourly meteorological data for precipitation, humidity and snow cover, vehicle traffic information, and road surface material information.

AP 42 Emissions Factors by Chapter