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 2014 NEI Final Version 1. You can choose from the following:

2014 NEI Final Version 1
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. Filters

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, hold down the CTRL key while clicking on options you would like to include in your query. To select multiple items in the order listed, click on your first selection, then hold down the SHIFT key and click on the last selection; this will highlight the two selections and every item between them. To unselect options, you can use the same method that was used when selecting.

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://19january2021snapshot.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:

Biogenics
Chemical and Allied Product Mfg
Fuel Comb. Elec. Util.
Fuel Comb. Industrial
Fuel Comb. Other
Highway Vehicles
Metals Processing
Miscellaneous
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 gray 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
PDF
Print

The user can navigate results, select the number of entries to be shown, and enter text in a search box to refine results. These tools are located at the top and bottom of the search results tables. The table columns can by sorted by clicking the column headings.

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:

Sector
State
Pollutant
Pollutant Type
Emissions
Unit of Measure

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

Sector
State
County
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:

Tier
State
Pollutant
Pollutant Type
Emissions
Unit of Measure

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

Tier
State
County
Pollutant
Pollutant Type
Emissions
Unit of Measure

4.3 Facility Summaries Search Results

The Facility Summary National Level table contains the following columns:

State
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Facility Summary State Level table contains the following columns:

State
Pollutant
Pollutant Type
Emissions
Unit of Measure

The Facility Summary Facility Level table contains the following columns:

State
County
Facility
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 pop-up that provides facility and National Emissions Inventory Data.

5. Usage Constraints

Information in the Envirofacts database can be freely accessed through the use of the searches. While the complexity of a search is determined by the user, searches that return a large volume of data may terminate prematurely due to system limitations. The constraints established for the enviro user account (the search uses this to connect to the Oracle database) are:

Each search is limited to 2.5 minutes of Central Processing Unit (CPU) time.
A single session can be 15 minutes in duration.
A session may stay idle for 7.5 minutes, at which time it will be terminated.
Develop searches that return small batches of data and terminate the session as soon as the searches have been executed, so others can access the database.

If the user selected report options that will result in a large amount of data to display within a browser, the system will provide a link to create a comma-separated value (CSV) file with the results that can be opened in Excel. The system will also provide individual state links if you would like to view the data in interactive reports.