NEI Search User Guide

The National Emissions Inventory (NEI) is a comprehensive and detailed estimate of air emissions of criteria pollutants, criteria precursors, and hazardous air pollutants from air emissions sources. The NEI is released every three years based primarily upon data provided by State, Local, and Tribal air agencies for sources in their jurisdictions and supplemented by data developed by the US EPA. The NEI is built using the Emissions Inventory System (EIS), first to collect the data from State, Local, and Tribal air agencies and then to blend that data with other data sources.

This is a brief user guide to the National Emissions Inventory Data search. The Search enables users to retrieve data from the NEI database in Envirofacts. To start, select an Inventory Year and one of the Summaries options. Based on your selections, additional filters will be available that can be used to define the search criteria and results.

1. Inventory Year Options

The Inventory Year is a required selection. The default is 2020 NEI. You can choose from the following:

2020 NEI
2017 NEI
2014 NEI Final Version 2
2011 NEI Version 2
2008 NEI Version 3

2. Summaries Options

Select from the following summaries options:

Sector Summaries
Tier 1 Summaries
Facility Summaries

2.1 Sector Summaries

Sector Summaries provide National, State, and County and Tribal summaries grouped by major source sectors by Criteria Air Pollutants (CAP) and Hazardous Air Pollutants (HAP).

2.2 Tier 1 Summaries

Tier 1 Summaries provide National, State, and County and Tribal summaries by Tier 1 by CAP pollutant(s). Tier 1 includes combustion, industrial, onroad/nonroad, and miscellaneous sectors. Tiers are used in plotting trends.

2.3 Facility Summaries

Facility Summaries provide National, State, and County and Tribal Facility totals by pollutant(s).

3. Filter Options

3.1 Level

The Level filter is available for every type of summary report. Select from:

Nation
State
County or Tribe
Facility – this option replaces the “County or Tribe” option when Facility Summaries has been selected.

3.2 Additional Filters

The additional filters available will vary based on the Summary report and Level chosen.

Additional filters include:

State
Counties/Tribes
Pollutant
Sector
Tier

In each of these filters, you can select one or more options. To use the multiple-selection boxes, click on options you would like to include in your query. To unselect options, click the item’s “x” button or expand the dropdown list and click in the item’s box to remove the checkmark.

3.2.1 State

Select a state or states. States are grouped by EPA Region. Federal (Fed) Waters and Tribal options are under “NA” at the end of the list.

3.2.2 Counties/Tribes

The Counties/Tribes filter will appear after the user has selected Facility Summaries and Facility Level. The filter will be populated with options after the user has selected from the State options (i.e., state, Tribal, or Fed Waters). Options in the Counties/Tribes list depend on which State options have been selected.

3.2.3 Pollutant

Select a pollutant or pollutants.

For Tier 1 Summaries, the Pollutant filter will contain the options of the following CAPs:

Ammonia – NH3 – (CAP)
Carbon Monoxide – CO – (CAP)
Lead – 7439921 – (CAP)
Nitrogen Oxides – NOX – (CAP)
PM10 Primary (Filt + Cond) – PM10-PRI – (CAP)
PM2.5 Primary (Filt + Cond) – PM25-PRI – (CAP)
Sulfur Dioxide – SO2 – (CAP)
Volatile Organic Compounds – VOC – (CAP)

For Sector summaries and Facility summaries, the Pollutant filter will contain the CAPs listed above, plus Elemental Carbon (EC) and Organic Carbon (OC). The list will also contain other pollutants (OTH), greenhouse gases (GHG), and the HAP chemical list. See https://www.epa.gov/haps/initial-list-hazardous-air-pollutants-modifications for the HAPs list.

3.2.4 Sector

The Sector filter will be available when Sector Summaries is selected. Select a sector or sectors.

3.2.5 Tier

The Tier filter will be available when Tier 1 Summaries is selected. Select a tier or tiers from the following:

Chemical and Allied Product Mfg
Fuel Comb. Elec. Util.
Fuel Comb. Industrial
Fuel Comb. Other
Highway Vehicles
Metals Processing
Miscellaneous
Natural Resources
Off Highway
Other Industrial Processes
Petroleum and Related Industries
Solvent Utilization
Storage and Transport
Waste Disposal and Recycling

4. Search Results

Search results will display after the Search button at the bottom of the screen is clicked. All search results show the dataset selected and search criteria, along with a table containing the search results. Buttons for the following actions and file formats are located in the upper left hand corner of each results table:

Copy
CSV
Excel
Print
JSON

On the results page, you can view pages using the navigation buttons below the table. The default number of records displayed on each page is 10, and you can adjust this using the dropdown to the right of the navigation buttons. A keyword search is available by clicking the filter icon in each column header, allowing you to filter the displayed results dynamically. Each column header also contains an arrow that can be clicked to sort the results in ascending or descending order.

4.1 Sector Summaries Search Results

The Sector Summary National Level table contains the following columns:

Sector
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Sector Summary State Level table contains the following columns:

State
State FIPS
Sector
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Sector Summary County or Tribe Level table contains the following columns:

State
State FIPS
County
Sector
County FIPS
Pollutant
Pollutant Type
Emissions
Unit of Measure

4.2 Tier 1 Summaries Search Results

The Tier 1 Summary National Level table contains the following columns:

Tier
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Tier 1 Summary State Level table contains the following columns:

State
State FIPS
Tier
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Tier 1 Summary County or Tribe Level table contains the following columns:

State
State FIPS
County
Tier
County FIPS
Pollutant
Pollutant Type
Emissions
Unit of Measure

4.3 Facility Summaries Search Results

The Facility Summary National Level table contains the following columns:

State
State FIPS
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Facility Summary State Level table contains the following columns:

State
State FIPS
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Facility Summary Facility Level table contains the following columns:

State
State FIPS
County
County FIPS
Facility
EIS ID
Address
City
ZIP Code
Pollutant
Pollutant Type
Emissions
Unit of Measure
Facility Type
NAICS Code
NAICS Description

The Facility Summary Facility Level report also returns a map of the facilities that match your search criteria. You can click on the points on the map to see a popup that provides facility and National Emissions Inventory Data.