Driver fatigue, recognized as a major safety problem in the transportation industry, is strongly influenced by employee work and sleep schedules. The work and rest hours of truck drivers have been regulated by Hours-of-Service (HoS) rules in the U.S since 1938, but it has become increasingly apparent these rules are inconsistent with the science of sleep and fatigue.The authors present and assess an innovative alternative safety management system, which takes a pro-active, science-based complimentary approach. This Risk-Informed Performance-Based (RIPB) safety system for sleep and fatigue management was implemented at one major trucking company, and involved the training of managers and dispatchers on scientific aspects of work assignments and a regular feedback system that assessed the fatigue risk of the work schedules. Driver fatigue was assessed using the Circadian Alertness Simulator (CAS) software system for simulating sleep and alertness based on work-rest patterns (Moore-Ede et al., 2004). Each driver was assigned a cumulative fatigue risk score based on logbook data processed for multiple one-month periods before and after the implementation of the safetymanagement system. The implementation of the RIPB safety management system resulted in a significant reduction of fatigue risk scores, a reduction of the rate and costs of accidents, and improvement of other operational parameters. The success of the RIPB system was sustained over an extended time period of more than three years, and thus could permit the relaxation of overly prescriptive HoS regulations.
Abstract