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TRB's National Cooperative Highway Research Program (NCHRP) Web-Only Document 246: Volume 1: TRAQS User Guide provides guidance for using the TRansportation Air Quality System (TRAQS). TRAQS is an open source software designed to conduct mobile air quality assessments for three primary purposes:

  1. Project-Level Conformity (Hot-Spot Analyses)
  2. National Environmental Policy Act (NEPA)
  3. General Transportation Planning

TRAQS is designed to streamline the model process and minimize any limitations of standalone software packages by integrating individual models and databases into a user-friendly, intuitive Graphical User Interface. It provides access to advanced modeling tools and mapping features. Overall, TRAQS offers the capabilities necessary to complete a Project-Level air quality analysis with increased accuracy and efficiencies.

Download the open source software as well as NCHRP Web-Only Document 246: Volume 2, TRAQS: A Combined Interface for Project-Level Air Quality Analysis, which accompany the Users Guide.

Note: TRAQS functions with versions of air quality models current as of December 2016: MOVES2014a and EMFAC2014.

TRAQS is written in Python, an open-source programming language. Developers or users who wish to customize or enhance TRAQS may download the source code from the project web page.

This software is offered as is, without warranty or promise of support of any kind either expressed or implied. Under no circumstance will the National Academy of Sciences or the Transportation Research Board (collectively "TRB") be liable for any loss or damage caused by the installation or operation of this product. TRB makes no representation or warranty of any kind, expressed or implied, in fact or in law, including without limitation, the warranty of merchantability or the warranty of fitness for a particular purpose, and shall not in any case be liable for any consequential or special damages.


Suggested Citation

National Academies of Sciences, Engineering, and Medicine. 2018. Volume 1: TRAQS User Guide. Washington, DC: The National Academies Press.

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Publication Info

153 pages |  8.5 x 11 |  DOI:

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