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Air Emissions Modeling


SPECIATE is the EPA's repository of volatile 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) and toxic air pollutant (TAP) emissions from PM and organic gas primary 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).

The SPECIATE 4.5 replaces SPECIATE 4.4, SPECIATE 4.3, SPECIATE 4.2 and SPECIATE 4.0. It includes 5,728 profiles for PM, volatile organic gas, and other gases profiles.

SPECIATE Data Browser

SPECIATE Documentation