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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

  • Policy Guidance on the Use of the November 1, 2006, Update to AP-42 for Re-entrained Road Dust for SIP Development and Transportation Conformity (PDF 255K) This memo provides additional details about the changes made to the AP-42 methods for road dust and how and when to use them in PM2.5 SIPs and transportation plan and transportation improvement program (TIP) conformity determinations. It also reaffirms that PM10 road dust estimates are unchanged from the previous version. This guidance supersedes the AP-42 portions of EPA's February 24, 2004, guidance, which addressed both MOBILE6.2 and AP-42. August 2, 2007.
  • Analysis of the Fine Fraction of Particulate Matter in Fugitive Dust. (PDF 1.3M) 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.
    Wrap Phase 1 (XLS 270K)
    Wrap Phase 2 (XLS 330K)
  • This 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.
    r13s0202_dec03.xls - December 2003 (XLS 18K)
  • This 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.
    r13s0202sample.wk4 - October 1998 (WK4 5M)
    r13s0202sample.xls - October 1998 (XLS 1.25M)

AP 42 Emissions Factors by Chapter

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