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Air Emissions Inventories

2008 National Emissions Inventory (NEI) Documentation (Draft)

The 2008 NEI Technical Support Document is a draft and using an improved format from past documents.  Although in draft form, this version provides all of the documentation available in past 2008 NEI releases as well as additional analysis about the sources of data used the NEI.  Placeholder sections are included so that major section numbers will not change in future versions.  This draft document will be replaced with updated versions as they become available.  Requests for updated sections can be made to the to the Info CHIEF Help Desk at

  • 2008 NEI Technical Support Document, Draft (updated 9/2013)
  • Supporting Data and Summaries (updated 9/2013) - See Section 8 of the Technical Support Document for a list of supporting files and their contents. The contents are accurate and not draft, though more supporting data may be added later. 
  • References (ZIP) (36.6MB) (updated 9/2013) - Throughout the documentation, references are made to EPA documents developed as part of the 2008 NEI effort. These are available in this zipped file. See also Section 8 of the Technical Support Document. 

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