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Air Emissions Modeling

2017 National Emissions Inventory (NEI) Modeling Files

The files linked below are the 2017 National Emissions Inventory (NEI) sector inventories in air quality modeling input format (flat file format). Downloadable sector flat files include biogenics, nonpoint, nonroad, onroad, point, and fires. These files are not a full modeling platform and do not include ancillary data or spatial surrogates. Documentation for the 2017 NEI is also linked below.

For additional information about the 2017 NEI or for data at alternative resolutions, visit: 2017 National Emissions Inventory (NEI) Data