ATSSA: Improving Driver Behavior with Infrastructure Safety Countermeasures

2 Improving Driver Behavior with Infrastructure Safety Countermeasures Overview and Acknowlegements R oadway crashes are a result of three primary contributing factors: human behavior, the roadway itself, and the vehicle. A combination of any or all of these factors may lead to a crash or increase the severity of a crash. However, research proves that the greatest potential to improve roadway safety is by a comprehensive approach that includes enforcement, education, emergency response, and engineering infrastructure safety countermeasures. Engineering countermeasures are roadway and infra- structure improvements implemented directly to the roadway network. Countermeasures (also known as strategies) include rumble strips, highly reflective signs and pavement markings, roadside hardware devices (guardrail and cable median barrier), traffic control devices, and other geometric improvements. These strategies can actually mitigate against behavior-related crashes by alerting drivers of an upcoming change in the driving environment that requires action or by providing positive guidance to prevent a collision. Countermeasures can minimize the consequences of a driver action that causes a vehicle to depart the roadway or collide with another conflicting vehicle. The following case studies illustrate how infrastructure safety countermeasures can impact driver behavior to improve roadway safety. They are grouped according to their ability to alert a driver, provide positive guidance that prevents a collision, or minimize the consequences once a vehicle has left the roadway. This document serves as a resource for understanding treatments and countermeasures that may reduce the number and severity of crashes due to driver error. ■ T he American Traffic Safety Services Association (ATSSA) and CH2M Hill, a global leader in consulting, design, design-build, operations, and program management, developed this report. The team examined a synthesis of previously completed ATSSA roadway safety case studies and with CH2M Hill fine- tuned those studies and developed new material for additional case studies contained in this publication. A wide variety of resources were used to develop this publication. A full list of references can be obtained upon request by emailing Communications@atssa.com with “References” in the subject line. The following individuals helped create this booklet: James S. Baron Project Manager Director of Communications American Traffic Safety Services Association Jacqueline Dowds-Bennett, P.E. CH2M Hill Colorado Springs, Colo. Michael K. Curtit, P.E. Traffic Liaison Engineer Missouri Department of Transportation Kimberly Kolody Silverman, P.E. Project Manager CH2M Hill Chicago Stephen Read, P.E. Highway Safety Improvement Program Manager Virginia Department of Transportation Nathan Smith Director of Government Relations American Traffic Safety Services Association Priscilla A. Tobias, P.E. State Safety Engineer Illinois Department of Transportation Roger A. Wentz President and CEO American Traffic Safety Services Association Allen Zeyher Copy Editor