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Due to a lapse in appropriations, EPA websites will not be regularly updated. In the event of an environmental emergency imminently threatening the safety of human life or where necessary to protect certain property, the EPA website will be updated with appropriate information. Please note that all information on the EPA website may not be up to date, and transactions and inquiries submitted to the EPA website may not be processed or responded to until appropriations are enacted.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Air Emissions Inventories

Emissions Development Tools

These air emission inventory tools are used to develop the National Emissions Inventory (NEI).  The PM Augmentation Tool is software developed by EPA to help ensure complete PM inventories by correcting inconsistencies in submitted data and filling gaps where possible.  WebFIRE is EPA's online emissions factor repository, retrieval, and development tool.  The SCC Tool is a searchable data base of the source classification codes that are used to characterize emissions in the NEI.

PM Augmentation


SCC Search Tool and Web Service