Black times: Temporal determinants of transport safety

doi:10.1016/S0001-4575(97)00021-3

Accident Analysis & Prevention

Volume 29, Issue 4, July 1997, Pages 417-430

https://doi.org/10.1016/S0001-4575(97)00021-3 Get rights and content

Abstract

This paper is concerned with whether transport accident risk tends to peak at particular times, in relation to both time of day and time on task, and with the underlying causes of such peaks. Macro-analyses confirmed the presence of a clear circadian (ca 24 hour) rhythm in road accident risk with a major peak at ca 03:00 but suggested that this rhythm could not be entirely accounted for in terms of drivers falling asleep at the wheel. Sleep propensity clearly shows a pronounced circadian rhythm and performance efficiency in wakeful subjects shows a similar trend implying that the 03:00 road accident peak may simply reflect lowered performance capabilities. However, there are ‘residual’ peaks in accidents at certain times of day that are difficult to account for in terms of circadian rhythmicity. It is suggested that these may reflect a time on task effect which shows a pronounced, but transient, 2–4 hour peak in risk. Only when individuals had been on duty for 12 hours or more did the risk exceed that found during the 2–4 hour peak. While an explanation for this transient peak is offered, the underlying reason for it is, as yet, uncertain and clearly warrants investigation in view of its practical implications. It is concluded that there are ‘black times’ when accidents are far more likely and that there is a strong need to investigate possible countermeasures.

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Fatigue and transportBlack times: Temporal determinants of transport safety

Abstract

Electroenceph-alography Clin. Neurophysiol.

Accid. Anal. Prev.

Shiftwork and rhythm

Acta Med. Scand.

Time of day effects on performance in a range of tasks

Psychon. Sci.

Temperament and time of day

The day and night performance of teleprinter switchboard operators

Occup. Psychol.

The original “twenty-four hour society”: issues of fatigue and accidents at sea

Diurnal variation

Effects on performance efficiency

Circadian variations in performance. Implications for abnormal work hours

Comparison of an eight-hour plant and a ten-hour plant

Fatigue and transport
Black times: Temporal determinants of transport safety