Enhanced seat belt reminders are an effective means of increasing seat belt use. It is important to optimize the design of these systems so that they increase belt use and are acceptable to vehicle occupants. This study examined the effects of duty cycle and duration on seat belt reminder effectiveness and annoyance. It also evaluated the European New Car Assessment Programme (Euro NCAP) duration requirement. Eighty part-time belt users experienced one of four seat belt reminders during a simulated drive and rated its effectiveness and annoyance every 45 seconds. Overall, enhanced reminders were rated as more effective than a basic reminder that complied with but did not exceed the U.S. federal requirements. Ratings of reminder effectiveness did not change significantly as reminder duration increased. Increasing the duty cycle of the chime and flashing icon in a reminder cycle did not influence system effectiveness, but it did make the system more annoying. Reducing the duty cycle of enhanced reminders would be one method of increasing user acceptance while retaining overall system effectiveness. Lastly, the variation in duration and duty cycle permitted under Euro NCAP requirements for seat belt reminders did not affect their perceived effectiveness. (Author/publisher)
Abstract