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Air Emissions Inventories

2020 National Emissions Inventory (NEI) Documentation

The NEI database includes air emissions sources of both criteria of both criteria and hazardous air pollutants. Data are available for many facilities and as county totals. The 2020 NEI is the next inventory on the three-year cycle and the EPA will create it using data provided by State, Local and Tribal air agencies. The Emissions Inventory System (EIS) helps the EPA to build the NEI.

2020 NEI Development Documentation

2020 NEI Plan