10. Work Unit No. (TRAIS) 9. Performing Organization Name and Address

Popular opinion has it that “road rage ” is increasingly prevalent and dangerous in the urban driving environment. Whether or not this opinion is true, driver frustration in congested conditions may lead to an increase in aggressive driving, a less intentionally malignant and more common subset of road rage. The potential for significant safety benefits might be realized if transportation professionals had a better understanding of some roadway factors and characteristics of the congested driving environment that induce irritation and perhaps contribute to the frequency of aggressive driving. This report documents the major first-year activities: literature review, focus groups, telephone survey, and development of potential traffic engineering mitigation measures. Researchers studied five focus groups consisting of six to ten individuals and a telephone survey of over 400 Dallas motorists to identify and quantify the pertinent factors increasing driver impatience, irritation, and stress in the congested driving environment. Based upon the survey responses, the research team developed reasonable and feasible traffic engineering mitigation measures (i.e., those factors related to the roadway itselfgeometrics, signs and markings, incident clearance activities, etc.) for furthe