Safety Evaluation of Lane and Shoulder Width Combinations on Rural, Two-Lane, Undivided Roads [Tech Brief]

11358782009PDFBriefFHWA-HRT-09-032Rural highwaysRoad shouldersTwo lane highwaysHighway safetyDesignHighwaysPavementsSafety and Human FactorsI22: Design of PavementsRailways and GuidewaysI82: Accidents and Transport InfrastructureUnited StatesUnited States. Federal Highway Administration. Office of Research, Development, and TechnologyJovanis, Paul PChen, Ko-YuPennsylvania State UniversityUnited States. Federal Highway Administration. Office of Research, Development, and TechnologyAmjadi, RoyaFederal Highway AdministrationThe Federal Highway Administration (FHWA) organized a pooled fund study of 26 States to evaluate low-cost safety strategies as part of its strategic highway safety effort. The purpose of the FHWA Low-Cost Safety Improvements Pooled Fund Study is to evaluate the safety effectiveness of several low-cost safety strategies presented in the National Cooperative Highway Research Program (NCHRP) Report 500 Series. Although not identified in the NCHRP Report 500 Series, one of the strategies selected for evaluation in the pooled fund study was the allocation of lane and shoulder width for fixed pavement widths on rural, two-lane, undivided roads (i.e., given a fixed roadway width for a rural, two-lane, undivided road, is it safer to provide wider shoulders or wider lanes?). The safety effectiveness of various allocations of total paved width had not previously been thoroughly documented, and this study is an attempt to provide an evaluation through scientifically rigorous procedures.75