California Department of Transportation

Division of Environmental Analysis (DEA) LINKS

square icon

Adobe Acrobat Reader is required to view and print PDF files. Adobe Acrobat is required to edit online forms and save them to your computer.

Get Acrobat Reader Image


Last Updated: Wednesday, April 6, 2016 11:26 AM

Caltrans Air Quality Research


Caltrans carried out early research regarding air quality and modeling, including development of the CALINE series of line-source dispersion models and two versions of comprehensive project-level air quality analysis guidance. Most of these materials are available on the internet at the Caltrans Division of Research and Innovation (DRI) web site as part of their scanned-image collection of documents from the Transportation Laboratory (Translab) library. Unless otherwise noted, links on this page are to the documents at the DRI web site.

As with most materials at the Caltrans web site, materials here are Copyright © by the State of California. Please contact Caltrans for more information before republication or other reuse.

Translab was reorganized as primarily a material testing organization in 1997. Its environmental technical assistance and research functions were transferred to the Division of Environmental Analysis.

Caline4, which was originally a mainframe computer program, became available as a MS-DOS executable file in 1994. It was distributed on floppy disk by mail and bulletin board system (later by web site). The Caline4 model now available at the Caltrans Air Quality web site has been recompiled to work in 32-bit Windows, but is otherwise unchanged from the PC version distributed in 1994. A "CL4" user interface for Caline4 was developed in 1996-98 to support use of Appendix B (Detailed Analysis) of the CO Protocol, and was updated in 2012 to address compatibility with more recent Windows systems.

The Caltrans Research and Innovation Division (DRI) archive of past research reports is in the "Research Publications and Databases" section of the site. Some documents listed below were prepared by Caltrans District office staff rather than directly by Translab.


Return to Air Quality Research Home Page