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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

Electronic Reporting of Air Emissions

Emissions Monitoring Knowledge Base

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