Washington (State). Dept. of Transportation. Office of Research and Library Services
Abstract
A pilot routine in-service performance evaluation (ISPE) was undertaken for impact attenuatorsfollowing the process outlined in NCHP 22-33. Controlled stop, rollover, vehicle mix, and secondary impacts on the roadside and roadway were evaluated as performance measures using data sourced from the Crash Location & Analysis System (CLAS) database and the WSDOT Engineering Crash Data Mart for years 2016 through 2020. Four Performance Assessment Levels, ranging from no exclusions of crash data to exclusions of crash data limited to vehicle type and speed limit were assessed. For all five performance measures, the study found no measurable differences between the performance of the major types of impact attenuators in use on state highways within WSDOT jurisdiction
