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Air Emissions Modeling


SPECIATE 5.1 Documentation

These documents describe the SPECIATE database, EPA’s repository of organic gas and particulate matter (PM) speciation profiles for air pollution sources. 

Documentation is provided for the SPECIATE 5.1, which is an addendum to the documentation for SPECIATE 5.0. These two versions are the most recent versions of SPECIATE. The addendum summarizes the SPECIATE program and provides the changes to the database since SPECIATE 5.0. The SPECIATE 5.0 final report provides a full history of the SPECIATE program. 

Documentation for earlier versions of SPECIATE including SPECIATE 4.5, SPECIATE 4.4, SPECIATE 4.3, SPECIATE 4.2, and SPECIATE 4.0 can be found in the SPECIATE Documentation Archive linked below.

Supporting Documents

Development of Mercury Speciation Factors for EPA's Air Emissions Modeling Programs - describes and serves as documentation for the mercury profiles added to SPECIATE 5.1.

Supporting information for "Emissions Inventory of PM2.5 Trace Elements across the United States" - describes the development of 168 PM profiles (added to version 4.3) Exit

EPA Publications on SPECIATE

The development and uses of EPAs SPECIATE database, as published in Atmospheric Pollution Research, 2010

An assessment of important SPECIATE profiles in the EPA emissions modeling platform and current data gaps, Atmospheric Environment, 2019Exit