Study Finds Lack of Safety Restraint in a Semi-Truck Increases Risk of Injury Regardless of Seating Position

LEXINGTON, Ky. (March 11, 2013) – Semi-truck drivers and sleeper berth passengers who were not using safety restraints, significantly increased the odds of injuries in moving collisions compared to those semi-truck occupants who were using occupant safety restraints, according to a recent study by the Kentucky Injury Prevention and Research Center (KIPRC) at the University of Kentucky College of Public Health.

The study reviewed 708 semi-truck collisions that included a passenger in the sleeper berth in Kentucky between 2000 and 2010.  This study was undertaken to determine if passengers in the sleeper berth were at higher risk of injury in a semi-truck collision compared to semi-truck drivers. 

Results of the study indicated that seating position was not a significant factor associated with an injury in a moving truck collision.  Rather, the lack of restraint use by both types of occupants was the main determining factor related to injury severity.  The other risk factor found to increase the odds of an injury was the area of first contact in the collision -- front or side of the semi-truck.

Dr. Terry Bunn, director of KIPRC and an author of the study, suggests that commercial vehicle carriers should implement and enforce a workplace policy that requires all vehicle occupants (drivers and sleeper berth passengers) to use occupant safety restraints while the semi-truck is moving.  Federal laws require all drivers, including commercial vehicle drivers, to wear seat belts while operating a motor vehicle.  There are no known laws requiring the use of occupant safety restraints in the sleeper berth, according to the authors.  Occupant restraints in the sleeper berth have been required since 1971 but they are not widely used. 

An informal survey of 20 commercial vehicle drivers revealed that the primary reason sleeper berth occupant restraints are not used is because they encumber sleep.  With that in mind, Bunn further suggests that commercial vehicle manufacturers should consider the redesign of sleeper berth restraint systems to allow for adequate protection of the occupant while not interfering with sleep.  A system so redesigned might improve use by sleeper berth passengers.

Dr. Bunn's study can be found at