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NONROAD2008a installation and updates

"NONROAD2008" is the overall version designation for the set of modeling files including the core model, default data files, graphical user interface (GUI), and reporting utility, released in April 2009. NONROAD2008a is essentially the same model, but with one small correction to the NOx emission factor data file which decreases the NOx emissions from land-based diesel engines by roughly 1 percent in 2007 (less in later years), which matches the emissions generated by NONROAD2005. The only change to the core model (nonroad.exe) is a change in the version number that gets included in the output files and reports generated by the reporting utility. The new version says: "Core Model ver 2008a, 07/06/09"

Known Issues:
Users who have MS-Office 2007 have reported problems getting the NONROAD reporting utility to work. This even includes users who install the runtime version of MS-Access 2002 that is provided with the NONROAD model. We have not been able to find a fix for this issue. But it is always possible to load the output file (e.g., .OUT or .BMX file) into spreadsheet software such as Excel, importing it as comma-delimited text. It may also be possible to use one of the multi-year postprocessor utilities to import the .OUT or .BMX files into MS-Access and create whatever queries you want, rather than relying on the queries built into the reporting utility.

Complete installation instructions, which must be read and followed carefully for successful model operation, are contained in the file:


Information about what has changed in this version of NONROAD is available in the Frequently Asked Questions (FAQ) document:

NOTE: You will need Adobe Acrobat Reader, available as a free download, to view some of the files on this page. See EPA's PDF page to learn more about PDF, and for a link to the free Acrobat Reader.

420f09021.pdf (5 pp, 190K, EPA420-F-09-021, April 2009)

Information about the changes in emission inventories estimated by NONROAD2008 relative to NONROAD2005 is presented in:

420f09020.pdf (29 pp, 100K, EPA420-F-09-020, April 2009)

Information specifically about the Graphic User Interface (GUI) updates are in the document:

nrgui08.zip (110K)

Basic instructions for the operation of the NONROAD model are contained in the NONROAD2005 User's Guide, which has not been updated for NONROAD2008. Detailed explanations of the default inputs are contained in the technical reports that are provided on the NONROAD Model web page along with this version of the model. These technical reports have not been updated from their NONROAD2005 versions, but much of the basic information is still valid.


Policy questions concerning use of the model for emission inventory preparation should be directed to your EPA regional office. For your regional office see:


Technical modeling questions that arise that are not covered by the above documents may be addressed to the nonroad modeling team by one of the following methods.

Email: nonroad@epa.gov
Fax: 734-214-4939

US Mail:
Nonroad Modeling Team
Assessment and Standards Division
Office of Transportation and Air Quality
US Environmental Protection Agency
2000 Traverwood Drive
Ann Arbor, MI 48105

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