Bus drivers often have irregular working hours and their work involve high levels of stress. These factors can lead to severe fatigue and the purpose of this study is to highlight how the working hours affect sleep, stress, fatigue and driving performance. The project includes four studies which all, in different ways, contributed to the understanding of bus drivers' working hours and the relation to fatigue. The hypotheses were that early morning shift, split shifts, long working hours and short hours of rest between shifts contribute to sleepiness, stress, fatigue and impaired driving performance, which together can result in increased safety. The overall results support these hypotheses. Generally speaking, sleepiness and fatigue while driving is perceived as a problem because drivers consider that this means impaired driving performance, which increases the risk of incidents and accidents. The following circumstances are considered to cause such problems: - A majority of drivers, 68 percent, believe that shifts longer than 10 hours is a major problem. - A majority, 62 percent, believe that varying the starting time of shifts is a major problem. - A majority, 56 percent, believe that rest periods shorter than 11 hours is a major problem. - 36 percent of drivers believe that split shift is a major problem. - 19 percent of drivers believe that early morning shift is a major problem. The above conditions contribute to the following: - 45 percent of drivers had trouble staying awake while driving at least twice a month. - 19 percent had over the past decade been involved in an incident due fatigue. - 17 percent had at some time during the past six months wanted to stop driving due to fatigue, but was not able to and 4 percent had stopped. - 7 percent had been involved in an accident caused by their own fatigue. The report concludes with a list of suggestions. (Author/publisher)
Abstract