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Air Emissions Modeling




SPECIATE is the EPA's repository of organic gas and particulate matter (PM) speciation profiles of air pollution sources.  Among the many uses of speciation data, these emission source profiles are used to:

  • create speciated emissions inventories for regional haze, PM, greenhouse gas (GHG), and photochemical air quality modeling;
  • estimate hazardous air pollutant (HAP) emissions from PM and organic gas emissions;
  • provide input to the Chemical Mass Balance (CMB) receptor model; and,
  • verify profiles derived from ambient measurements by multivariate receptor models (e.g., factor analysis and positive matrix factorization).

SPECIATE 5.1 replaces all previous versions of SPECIATE. It includes 6,746 PM, gas, and other profiles.