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Clearinghouse for Inventories and Emissions Factors (CHIEF)

Air Emissions Inventories

Learn about the amount and type of pollutants released by humans and natural sources. 

Air Emissions Modeling

Find emissions model input based on National Emission Inventory databases.

Air Emissions Factors and Quantification

  • Basic Information about Air Emissions Factors
  • AP-42
  • Emissions Factors Estimation Tools
  • Web Factor Information Retrieval System (WebFIRE)

Electronic Reporting of Air Emissions

  • Basic Information about Electronic Reporting
  • Compliance and Emissions Data Reporting Interface (CEDRI)
  • Electronic Reporting Tool (ERT)
  • WebFIRE

Emissions Monitoring Knowledge Base

Basic information about monitoring techniques by industry type and control technique.

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Last updated on November 16, 2021
United States Environmental Protection Agency

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