An exploratory study of hours of service and its safety impact on motorists

There were an estimated 438,000 truck crashes in 2014 that led to approximately 110,000 injuries and 3903 deaths (HTSA and DoT, 2014). Truck driver fatigue has been cited as a major reason for these accidents Federal Motor Carrier Safety & Administration, 2015 (). In July 2013, the Federal Motor Carrier Safety Association (FMCSA) revised its hours of service (HOS) regulatory policy, which restricts the number of duty and driving hours a truck driver can operate in order to reduce the fatigue related accidents involving trucks. The revision changed the unlimited restart (allows truck drivers to reset their duty time log back to zero) provision by restricting it to 1 restart per 168 h (1 week) and added that the restart must span two consecutive 1 a.m. to 5 a.m. periods. Lawmakers suspended these two aspects of the restart provision in the Consolidated and Further Continuing Appropriations act on December 16, 2014 until more analysis was completed on the efficacy of these regulations due to unintended consequences that allegedly negatively affected motorist's safety. Countering truck driver fatigue is an important issue and an extremely difficult task because of the many confounding aspects that can cause fatigue. The new regulation set forth in July 2013, was supposed to lessen fatigue and thus reduce accidents caused by truck drivers. The current HOS regulation was in place for approximately 16 months, producing enough data for a statistical analysis of its effects on truck driver safety. This research found that by comparing truck driving safety data prior to the change in July of 2013 (the unlimited restart provision) to truck driving safety data during the enactment of the 1 restart per 168-h restriction and 1 a.m. to 5 a.m. provision that the percent of accidents caused by truck drivers did not decrease. Furthermore, this research found that the HOS changes implemented on July 1, 2013 have not led to a significant change in accidents involved and caused by truck drivers. These results suggest that other factors appear to be linked to motorists' safety, rather than the updated HOS regulation.