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AP–42 Methods for Re-entrained Dust

Motor vehicle emissions inventories for PM10 and PM2.5 are comprised of four components: exhaust emissions, emissions from brake wear, emissions from tire wear, and re-entrained road dust. EPA's methodologies for estimating PM emissions from re-entrained road dust are found in Chapter 13 of Compilation of Air Pollutant Emission Factors, AP-42. The sections of AP-42 that address re-entrained road dust emissions are: Section 13.2.1 (Paved Roads) and Section 13.2.2 (Unpaved Roads).

State and local agencies currently use the latest versions of these sections of AP-42 for calculating re-entrained road dust in PM SIP development and regional conformity analyses, as applicable, unless EPA has approved an alternate method.

Policy & Guidance

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Updated: 3/20/2015
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