May 15, 2009

The Public Release (Version 2) of Surrogate Safety Assessment Model (SSAM)

The Public Release (Version 2) of Surrogate Safety Assessment Model (SSAM) is now available for free downloading at . The SSAM is a software application designed to conduct conflict analysis and to perform statistical analysis of vehicle trajectory data output from microscopic traffic simulation models including VISSIM, AIMSUN, Paramics, and TEXAS. The software computes a number of surrogate measures of safety for each conflict that is identified in the trajectory data and then computes summaries (mean, max, etc.) of each surrogate measure. This approach circumvents the need to wait for "abnormally high" crashes to actually occur, allows assessments of hypothetical designs and control alternatives, and is applicable to facilities where traditional, volume-base crash-prediction model have not been established.

In addition, following lists some useful resources and contact information for your reference:

For program information: contact Clayton Chen, FHWA HRDS Project Manager at 202-493-3054,

For additional SSAM information -- SSAM website:

SSAM Technical Support: contact Steve Shelby (Siemens) by e-mail or phone (520) 290-8006 ext. 115

To download the Version 2 of SSAM software (free-of-charge): and look for "download registration"

SSAM Software User Manual:

SSAM and Validation -- Final Report:

May 6, 2009

Traffic Calming on Main Roads Through Rural Communities

Speed management is a significant challenge for most communities in the United States. It is particularly true for small, rural communities where the main roadway through the town serves a dual role.This TechBrief summarizes an evaluation of the effects on speed of low-cost, traffic-calming treatments on main rural highways passing through small, rural communities in Iowa. Read more at

March 13, 2008

Read the latest Hot Topics

The March issue of Minnesota LTAP Hot Topics is available now.

Read about:

-Mini paver video rolls on LTAP Web site
-Guidelines help agencies with ADA-required transition plans
-Tool kit offers ADA best practices for state, local government
-Manual geared to make bicycling safe, attractive option
-Cultural factors seen as crucial to improving rural safety

and more...