A study evaluating the impacts of work shifts on driver alertness has been published by the National Transport Commission (NTC) and the Cooperative Research Centre for Alertness, Safety and Productivity (Alertness CRC).
Described by the researchers as a “world-first”, the study into heavy vehicle driver fatigue analysed shift start time, the number of consecutive shifts, shift length, shift rotation, rest breaks and their likely impact on driver drowsiness and fatigue.
“We found that slow eye and eyelid movements, longer blink duration and prolonged eye closure are reliable predictors of drowsiness and fatigue,” said Spokesperson and Theme Leader for Alertness CRC, Associate Professor Mark Howard.
The study looked at more than 300 heavy vehicle driver shifts both in-vehicle and in a laboratory, as well as 150,000 samples of retrospective data. It confirmed a scientific link between alertness and drowsiness patterns associated with specific work shifts for heavy vehicle driving.
- Greatest alertness levels can be achieved under current standard driving hours for shifts starting between 6 a.m. – 8 a.m., including all rest breaks.
- Greatest risk of an increase in drowsiness occurs:
- After 15 hours of day driving (when a driver starts a shift before 9 a.m.)
- After 6–8 hours of night driving (when a driver starts a shift in the afternoon or evening)
- After five consecutive shifts when driving again for over 13 hours
- When driving an early shift that starts after midnight and before 6 a.m.
- During the first 1–2 night shifts a driver undertakes and during long night shift sequences
- When a driver undertakes a backward shift rotation (from an evening, back to afternoon, or an afternoon back to a morning start)
- After long shift sequences of more than seven shifts
- During nose-to-tail shifts where a seven-hour break only enables five hours of sleep
“This is critical new evidence that will ultimately help to decrease heavy vehicle fatigue risk at a time when the nation’s freight task is expected to double by 2030,” said NTC Chief Executive Officer Dr Gillian Miles.
Alertness CRC conducted the research as part of a wider collaboration including the NTC, the Australian Government, Transport for NSW, Austin Health, Monash University, the Institute for Breathing and Sleep and the heavy vehicle industry.