Development of Crash Reduction Factors for Bicycle-Related Safety Countermeasures

Developing quality California-specific crash modification factors (CMFs) for bicycle-related safety countermeasures will support practitioners in making more informed decisions about infrastructure improvement projects. The researchers identified a comprehensive list of countermeasures, identified existing CMFs and reviewed their quality and applicability to California, determined key bicycle injury and fatality crash patterns in the state, prioritized potential bicycle safety countermeasures for study, and identified potential study sites. The results show there is limited availability of relevant and high quality CMFs. Analysis of severe and fatal bicycle crashes point to the need for study of segment bicycle safety treatments, like Class IV bicycle lanes, because of the prevalence of segment parallel path and overtaking crashes, especially among fatal crashes. The researchers compiled a data set of existing and planned Class IV bicycle lanes, which are increasingly common throughout California, and identified existing bicycle count data collected on those facilities.