Safety evaluation of intersection conflict warning systems (ICWS), TechBrief

2016PDFTech ReportFHWA-HRT-15-076;HRDS-20/02-16(200)EIntersectionsTraffic conflictsTraffic safetyHighway safetyWarning devicesIntersection conflict warningsSafety evaluationsEmpirical BayesianUnited StatesUnited States. Federal Highway Administration. Office of Research, Development, and TechnologyHimes, ScottGross, Frank B.Persaud, BhagwantEccles, Kimberly A.VHB/Vanasse Hangen Brustlin, Inc.United States. Federal Highway Administration. Office of Research, Development, and TechnologyFederal Highway AdministrationThe Federal Highway Administration (FHWA) organized 40 States to participate in the FHWA Evaluation of LowCost Safety Improvements Pooled Fund Study (ELCSI-PFS) as part of its strategic highway safety plan support effort. The goal of the ELCSI-PFS research is to identify new safety strategies that effectively reduce crashes and promote them for nationwide installation by providing measures of their safety effectiveness and benefit to costratios through research. One of the strategies selected by member States to be evaluated for this study is intersection conflict warning systems (ICWS). This strategy isintended to reduce the frequency of crashes by alerting drivers of conflicting vehicles on adjacent approaches at unsignalized intersections, particularly those with one-wayor two-way stop control. Few studies have explored the safety effectiveness ofICWS; the effectiveness has not been shown for four-legged intersections. This study sought to fill this knowledge gap