The level of safety for motorists on U.S. roads varies widely. Controlled-access freeways, with no at-grade intersections or driveways, provide the highest level of safety among road types. Other safety enhancing features of roadways include medians, roadside clear zones, guardrails, median barriers, and intersection turn lanes. Highway agencies have limited funds for improving the safety features of roadways, so it is important that their investment decisions are made in a way that provides maximum benefits to motorists and to the public at large. Roadway and roadside improvements will have a key role in improving the overall safety performance of the highway system. However, a key to understanding the nature of safety on the highway system is to recognize that, while every crash occurs on some road segment, this does not imply that the design or operational characteristics of that road segment are necessarily the cause of those crashes. While driver and vehicle factors contribute to the causation of many more crashes than road factors, risk maps of the road system can help to identify roadways where there are opportunities to improve safety. Currently, there is no systematic road assessment program in North America to inform motorists of the level of safety on the roads they travel or to help auto clubs and others provide informed advice to highway agencies on needs for safety improvement. Systematic road assessment programs have begun in Europe and Australia. The European Road Assessment Program (EuroRAP) was started in 2000 and the Australian Road Assessment Program (AusRAP) was started in 2003 to develop and implement systematic road assessment protocols. The AAA Foundation for Traffic Safety (AAAFTS) is completing a pilot program to test the technological and political feasibility of instituting a U.S. Road Assessment Program (usRAP). This work has been funded by AAAFTS, with support from FIA Foundation for the Automobile and Society and the International Road Assessment Program (iRAP), and the Midwest Transportation Consortium (MTC) at Iowa State University. The pilot program is examining the various technological barriers—are appropriate data available and how should those data be aggregated? The pilot test is also examining political barriers—will highway agencies cooperate with such a program and can liability concerns be overcome? This pilot program is focusing attention on the need for highway safety improvement and starting a national dialogue on the issue. There is concern that crash investigations and existing road safety data in many jurisdictions are not adequate to support comprehensive analyses of road safety features. It is envisioned that the national dialogue would help create public support for higher funding to upgrade data systems and make road safety improvements. This report is organized as follows. Section 2 presents a review of existing road assessment programs and related initiatives. Section 3 presents the results of the usRAP pilot studies conducted in Iowa and Michigan. Section 4 discusses key issues for usRAP implementation and Section 5 presents specific recommendations for usRAP implementation resulting from this pilot program. Section 6 discusses potential next steps in the usRAP program. Appendix A presents the preliminary usRAP Road Protection Score (RPS) criteria used in the pilot studies. (Author/publisher)
Samenvatting