2002 National Emissions Inventory Data & 

Documentation

Inventory Documentation

Inventory Data

Explanation of File Formats

General Inventory Information

2002 National Emission Inventory (NEI) Preparation Plan - Final August 2004 (PDF 230K)

2002 National Emission Inventory (NEI) Briefing - March 2004 (PDF 1.15M) 

Inventory Documentation

Point

Documentation for the Final 2002 Point Source National Emissions Inventory - July 2006 (PDF 270K) 

Emission Inventory Quality Assurance and Data Augmentation for Point Sources - updated July 2006 

(PDF 250K)

Documentation for the 2002 Electric Generating Unit (EGU) National Emissions Inventory (NEI) -

September 2004 (PDF 125K)

Describes how EPA created emission estimates for EGUs for the draft 2002 NEI. These estimates remain 

in the Final 2002 point source file wherever State, Local, or Tribal submittals did not replace them.

Revision of the PM emissions from natural gas combustion in the final version of the 2002 NEI. -

August 2005 (PDF 68K)

Point Source Augmentation Support Files (cited in Augmentation Report)

 EIS Code Look up tables Updated October 6, 2008 

 Mercury Speciation (ZIP 30K) Updated December 19, 2006. Profiles were updated for 2002 

NEI source categories including new data for mobile sources. 

 NEI2005 Look up tables other than those included in EIS Code Look up Tables Updated April 4, 

2009 

 Toxicity weighting factors (MDB 290K) Updated January 10, 2007. 

 Ratios to adjust PM (XLS 37K) 

 Stack parameter defaults (MDB 1M) 

 NEI Pollutant Codes with Chemical Identification Standard - Readme file (PDF 13K) 

 NEI Pollutant Codes with Chemical Identification Standard (MDB 520K) January 2007 

 CAP source category crosswalk (MDB 2.7M) 

 HAP source category crosswalk (MDB 8M) 

 PM augmentation ratios (ZIP 90MB) - Updated June 2007 

 SCC emission release point crosswalk (MDB 188K) 

 SIC/NAICS 3km ERP acceptable (MDB 130K) 

 ZIP code tables (MDB 10M) 

Nonpoint

Documentation For The Final 2002 Nonpoint Sector (Feb 06 Version) National Emission Inventory For 

Criteria And Hazardous Air Pollutants, including Appendix A: Criteria and HAP Emissions Estimation 

Methodology - Final, July 2006. (PDF 2.3M)

Appendix B: Electronic Appendix Containing Data Sets Used to Spatially Allocate National Activity Data 
and Emissions to Counties (MDB 7.5M)

Appendix C: Emission Factors and County-Level Activity Data Used to Calculate 2002 Emissions by 

Category (ZIP 4.4M)

Appendix D: Electronic Appendix Summary of Changes Made to State, Local, and Tribal (S/L/T) 

Inventory Data to Prepare the Draft 2002 and the Final Nonpoint Source NEI (XLS 1M)

Review of Wood Heater and Fireplace Emissions Factors - December 2006 (PDF 135K)

National Emission Inventory: Ammonia Emissions from Animal Agricultural Operations, Revised Draft 

Report - April 2005 (PDF 9K)

Solvent Mass Balance Approach For Estimating VOC Emissions From Eleven Nonpoint Solvent Source 

Categories - Draft March 28, 2005. (PDF 3.5M)

Mobile

Documentation Updates for 2002 Version 4 - November 2008. 

Documentation For The Final 2002 Mobile National Emissions Inventory - Version 3 - September 2007. 

(PDF 986K)

Documentation For The Onroad National Emissions Inventory for Base Years 1970-2002 - January 

2004. (PDF 265K)

Documentation For Aircraft, Commercial Marine Vessel, Locomotive, And Other Nonroad Components 

Of The National Emissions Inventory, Volume I - Methodology - September 2005. (PDF 700K)

Documentation For Aircraft, Commercial Marine Vessel, Locomotive, And Other Nonroad Components 

Of The National Emissions Inventory, Volume II - Supporting Documentation (PDF 17K)

General Aircraft References (PDF 11M)

General Commercial Marine Vessel References (PDF 6.5M)

General Locomotive References (PDF 4.7M)

General Other Nonroad References (PDF 20M)

Inventory Data

Point Sector Data - Version 3 of the 2002 NEI - The following zipped Access summary files were 

created in September 2007 and contain annual emissions in tons per year. if you have any questions, 

please contact Roy Huntley or (919) 541-1060. Questions on Hazardous Air Pollutants (HAPs) and the 

ALLNEI CAP file should be directed to Anne Pope or (919) 541-5373.

Point Facility Summary - For both CAPs and HAPs (18 MB)

SCC Summary - For both CAPs and HAPs at county, state and national level. (31 MB) 

ALLNEI_HAP_Annual_01232008 - Point stack summary data for HAPs only (129 MB)

ALLNEICAP_Annual_11302007 - Point stack summary data for CAPs only (174 MB)

NEI_2002_Point_Facility_ID_History_01182008 - Facility identifiers, names and locations for sites in 

current and previous version of the NEI (Created 1/2008) (22 MB) If you have any questions, please 

contact Anne Pope or (919) 541-5373. 

Nonpoint Sector Data - Version 3 of the 2002 NEI - The following zipped Access summary file was 

created in September 2007 and contain annual emissions in tons per year. If you have any questions, 

please contact Roy Huntley or (919) 541-1060. 

SCC Summary - For both CAPs and HAPs at the national, state, and county level. (73 MB)

All Sector Data - Version 3 of the 2002 NEI - The following zipped Access file was created in October 

2007 and contains Tier 1, Tier 2, and Tier 3 summaries for criteria polluntants only. Annual emissions 

are in tons per year. If you have any questions, please contact Roy Huntley or (919) 541-1060.

Tier Summary - County, State and National Level (52 MB)
Mobile Sector Data - Version 4 of the 2002 NEI - The following zipped Access files were created in 

September 2008. Annual emissions are in tons per year with zero emission values removed. Nonroad 

files include aircraft, locomotive, and commerical marine vessels. No code description are added to 

these files to limit the file size. SCC and pollutant descriptions are provided at EIS Code Tables. Point of 

contact for the Mobile Section is Laurel Driver or (919) 541-2859.

SCC Summary

Nonroad County 9 of 9 (354.53 MB)

Nonroad State and National (12.97 MB)

Onroad County 5 of 5 (209.38 MB)

Onroad National and State (17.98 MB)

Auxillary Files - NMIM National County Database (NCD) Files - The following files were created in July 

2007. The zipped file contains the MySQL NCD tables and external files used to develop the 2002 NEI 

Version 3 emissions estimates. 

NCD Files (181 MB)

2002 Nonroad Supplement GIS Data - For nonroad source categories, activity or fuel use data are 

not readily available for all counties in the U.S. Therefore, emissions often are calculated at the national 

level and allocated to individual counties based on appropriated surrogates. Often the surrogate data 

are available as Geographic Information System (GIS) data sets. Three sets of files are provided here 

which contain the GIS data used to spatially allocate emissions for aircraft, commerical marine vessels 

(CMV), and locomotives. All of the 2002 data used in this inventory effort were obtained from the 

Department of Transportation's Bureau of Transportation Statistics (BTS) or the FAA's Emissions 

Dispersion and Modeling System (EDMS)

2002 Nonroad Supplement GIS Data

Biogenic Sector Data

Biogenic Sector Data and Readme for biogenic data - The biogenic emissions data has not been updated 

since it was originally posted in March 2004. It has been moved to the Final 2002 NEI FTP site for your 

convenience. 

National Emissions Inventory Input Format

NEI Code Tables 

Posted Updates to Data

If you would like to submit comments or recommendations, please send an email to the Info Chief 

Help Desk at info.chief@epa.gov. The subject should be "2002 final NEI comment." As time and 

resources permit the 2002 inventory will be updated and corrected. This information is also posted in 

the folder General_Inventory_Information on the FTP site. 

 February 23, 2006: Files related to the following areas of the 

NEI are not included in this release but will be available 

shortly:

Emission estimates and documentation for CAP and HAP 

emissions from Wildfires and Managed Burns. 

Nonpoint sector documentation. 

Point sector documentation and QA augmentation report. 

 March 1, 2006: 

Readmes were added to national ASCII text files and 

reposted. 
SCC, SIC, and facility summary files for point sources were 

posted. CAP only. 

SCC summary files for nonroad and onroad mobile sources 

were posted. CAP only. 

SCC summary files for nonpoint sources were posted. CAP 

only. 

All sector (sources) Tier 1, 2 and 3 summary files were 

posted (all_sector_summary_data folder). CAP only. 

 March 9, 2006: 

The nonroad national ASCII zip file was reposted. The EM 

table was too large and was divided into two tables. 

The onroad and nonroad county summary files were 

reposted. Files containing the individual County-SCCPollutant Emissions values in tons per year for 2002 are 

being provided in a set of five tab-delimited ASCII format 

files, because a single file for the entire US is too large to be 

readable in most systems. 

The CAP nonroad and onroad SCC summary files were 

updated. 

The CAP point SCC and SIC summary files were updated. 

The CAP nonpoint SCC summary file was updated. 

The Tier 1 through Tier 3 CAP all sector files were updated. 

 March 15, 2006: 

Biogenic data from March 2004 was moved to 2002 NEI 

final FTP site. No changes were made to the data. 

A point source facility file was added to the 

point_sector_data which includes facility IDs and history 

from 1999 to 2002. A readme file is included with the 

zipped MS Access file. 

The augmentation report, NEI Quality Assurance and Data 

Augmentation for Point Sources, dated February 2005, was 

added to the inventory_documentation folder. 

Links to the NIF code tables and NOF structure 

specifications were added to this webpage in the table 

above. 

 March 22, 2006: 

The following point sector files were updated:

nei2002_point_state_summary.zip

nei2002_point_national_summary.zip

nei2002_point_county_summary.zip

nei2002_cap_sicsummary.zip

nei2002_cap_point_sccsummary.zip

nei2002_cap_facilitysummary.zip 

The following all sector files were updated:

nei2002_cap_all_sector_tier3annual_summary.zip

nei2002_cap_all_sector_tier2annual_summary.zip

nei2002_cap_all_sector_tier1annual_summary.zip 

 April 12, 2006: 

The following file was updated:

nei2002_point_detailed_data_040506.zip. Detailed national 

ASCII files prepared in NEI Output Format (NOF) - Data 

updated. 

 May 31, 2006: 

The following regional MS Access files prepared in NEI 

Output Format (NOF) were posted:

nofv3_msaccess2002_jan05_pointregion1.zip

nofv3_msaccess2002_jan05_pointregion2.zip

nofv3_msaccess2002_jan05_pointregion3.zip
nofv3_msaccess2002_jan05_pointregion4.zip

nofv3_msaccess2002_jan05_pointregion5.zip

nofv3_msaccess2002_jan05_pointregion6.zip

nofv3_msaccess2002_jan05_pointregion7.zip

nofv3_msaccess2002_jan05_pointregion8.zip

nofv3_msaccess2002_jan05_pointregion9.zip

nofv3_msaccess2002_jan05_pointregion10.zip 

 Oct 20, 2006:

Summaries of changes between version 1 and version 2.

 August 2, 2007

2002 Aircraft emission estimates have been revised for 

lead, arsenic, and mercury and to place all airports at 

latitude/longitude (point source) locations. Please see the 

README file posted with the data. 

 October 15, 2007

Point Facility Summary file for both CAPS and HAPs was 

posted 

Point SCC Summary file for both CAPs and HAPs at the 

county, state, and national level was posted 

Nonpoint SCC Summary file for both CAPs and HAPs at the 

county, state, and national level was posted 

Tier Summary file for CAP was posted 

Onroad/nonroad SCC summaries for CAP and HAP were 

posted. 

 October 22, 2008

2002 Lead emissions at airports have been revised. The 

Technical Support Document (TSD) posted here provides 

the methodology used to estimate airport-specific lead 

emissions. The airport-specific lead estimates for 2002 are 

also provided in this TSD. The 2002 NEI does not include 

these updates. Subsequent NEI base years will incorporate 

the methods documented here. 

 November 18, 2008

Onroad and Nonroad documentation updates for 2002 V4 

were added. 

SCC Summaries for 2002 V4 replaced V3 Onroad and 

Nonroad