Shifts, duration of work and accident risk of bus drivers

Abstract This paper contains the results of a repetitive and comprehensive analysis of accidents of bus drivers, highlighting different aspects of the aetiology of bus drivers' accidents. The results presented in this paper indicate a strong effect of the type of shift on accident risk. Shifts starting in the morning appeared to have a higher risk than shifts starting in the afternoon. Furthermore a certain association could be detected within each type of shift, with the starting hour of the service reflecting the influence of the starting condition of the worker. The paper continues with the analyses of the pattern of accident risk during the course of various types of shift. A characteristic pattern can be demonstrated, namely that accident risk during the early shift is relatively low at the beginning of task operation, reaches a peak at about the third or fourth hour of service, followed by a decline and then another increase during the last hours of task operation. Accident risk during the late shift is relatively high at the beginning of service and then declines towards the end of service. In the first, morning part of the split shift a less clear picture can be detected, while in the second, afternoon part an inverted U-shape can be demonstrated. On the basis of the results of this study and a discussion about the role of time of day and time on task in influencing accident risk, it is concluded that, while allowance must be made for certain variations related to the time of day, in accident research one should take full account of the effects of the structure of the work together with the duration of the work, i.e. time on task. Keywords: Accident riskShift workBus driversTask effectsDuration of workDiurnal variation