When determining the causes of freight-related accidents, researchers need to disentangle the complex interactions among a range of causal and confounding factors, such as hours of service, time of day, traffic density, roadway type, environmental conditions, and driver behavior and characteristics. This study is seeking to uncover relationships between driver hours of service and a set of potential confounding factors related to time of day, including circadian rhythm and traffic density variation. Following the development of relationships between safety critical events (SCEs) and the above factors, the researchers are exploring opportunities for, and constraints to, the deployment of operational changes to reduce SCEs. Such operational strategies include actions that both the freight industry and transportation agencies could take, such as delivery schedule adjustments to avoid highest risk time of day and hours of service interactions. The results could lead to deeper insights into commercial motor vehicle crash risk and causation, with important safety implications and applications beyond hours of service regulations.
Principal Investigators:
Salavador Hernandez, Oregon State University
Eric Jessup, School of Economic Sciences, WSU
Sponsor: PacTrans
Scheduled completion: January 2018