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Air Emissions Factors and Quantification

  • What is an emission factor?

    An emissions factor is a representative value that attempts to relate the quantity of a pollutant emitted with an industrial activity.

Emissions factors are tools for building emissions inventories, guiding air quality management decisions and developing emissions control strategies.  

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Air Emissions Factors / AP-42

  •  Basic Information About Air Emissions Factors and Quantification
  •  AP-42 Compilation of Air Pollutant Emissions Factors

Web Factor and Information Retrieval System (WebFIRE)

  •  WebFIRE

Emissions Estimation Tools

  • Spreadsheets and Methodology Documents
  • Software:  TANKS, SPECIATE, LandGEM, WATER9

See also Clearinghouse for Inventories and Emissions Factors (CHIEF)

Contact Us about Air Emissions Factors to ask a question, provide feedback, or report a problem.
Last updated on July 9, 2026
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