Consumer acceptance of enhanced seat belt reminders, a gearshift interlock, or different speed-limiting interlocks to encourage seat belt use following a brief hands-on experience

August 2019

Seat belt interlock systems that restrict the use of the vehicle or a vehicle feature when an occupant is unbelted are more effective for increasing seat belt use than auditory tones and visual icons that cue belt use; however, the public has found, and may still may find, seat belt interlock systems unacceptable. The current study collected driver opinions about whether 3 seat belt reminder systems and 3 interlock systems would increase seat belt use and whether the technologies were acceptable. The interlock systems either restricted speed or prevented the vehicle from being shifted into gear. Twenty-eight volunteers, 22 who did not always use a belt and 6 who routinely did, drove 6 vehicles equipped with a seat belt reminder, speed-limiting interlock system, or gearshift interlock system on a closed course while unbelted or while completing tasks that presented opportunities for driving unbelted. Participants indicated their level of agreement from 1 (strongly disagree) to 5 (strongly agree) with 5 statements after driving each vehicle. Participants more strongly agreed that each interlock system would make them buckle up more frequently than 2 of the 3 seat belt reminder systems. A similar pattern of results was observed when participants rank ordered each technology from most to least effective for increasing belt use. Agreement about finding the various technologies acceptable in a personal vehicle, requiring them in a personal vehicle, avoiding purchasing a vehicle with them, or finding ways to circumvent them was not significantly different by technology. When asked to circumvent each of the 3 seat belt interlock systems, participants most commonly buckled the belt and sat on it, routed the seat belt behind their back after sitting in the seat, or performed various sequences of buckling and unbuckling to defeat each system. In a poststudy interview, most participants raised safety concerns about the seat belt interlock systems they experienced, particularly the speed-limiting interlock systems. Hence, although the findings indicate that seat belt interlocks are perceived as more effective for increasing seat belt use than reminders and are no more or less acceptable following a brief hands-on experience, the technology created safety concerns that were not expressed for seat belt reminders and may impede acceptance.