Air Emissions Inventories

2011 National Emissions Inventory (NEI) Documentation

Documentation for the 2011 NEI is ongoing at this time. Updates will be posted as available.  Requests for additional information can be made to the Info CHIEF Help Desk at

  • Nonpoint Emissions Tool and Methods

    • Nonpoint Categories (xlsx)(1 pg, 18 K) that EPA is developing emission estimates for or planning to pull forward the 2008 estimates for use in 2011, if not provided by Agencies. (Updated September 2012)
    • Data and documentation:  MS Excel spreadsheets with emission factors, activities and county level allocation factors, and MS Word documents that describe the methodology used to estimate emissions
    • Oil & Gas Emission Estimation Tool: (ZIP 6.5 MB) Includes the Access database tool, Supporting Materials, Documentation and Instructions for version 2. (Updated November 2014)
  • Onroad Mobile Resources

    • Example run specification file:  Sample county run specification file for 2011 NEI.
    • Generic CDB Creator (ZIP)(13 pp, 2 MB) XML template for creating CDBs for submission to the NEI
    • QA Tools:  Tools to QA CDBs and to create the required QA Reports for EIS CDB submission
    • CDB Sampler Header (xml)(1 pg, 2 K) file that can be edited for EIS submittal as an alternative to creating it via Bridge Tool Staging Tables
    • National County Checklist (xlsx)(1 pg, 101 K) : checklist that indicates which tables the agency has revised from EPA's defaults for each county's CDB