Introduction: Fatigue is prevalent among seafarers and is linked to an increased risk of accidents,
as well as adverse effects on both their mental and physical health. Previous studies
have identified significant differences in fatigue risk associated with varying work
schedules and roster patterns. However, most research has focused on shipping, tanker,
fishing, or naval vessels, leaving a gap in our understanding of how different shift
schedules and weekly roster patterns affect ferry operations. In the ferry industry,
shift patterns and rosters differ from those in other maritime sectors due to unique
operational requirements. This study explores the relationship between roster patterns,
work schedules, job roles, and fatigue among seafarers on board ferries in UK waters.
Methods: Sixty- three seafarers participated in this study during routine operations on ferry
routes in and out of the UK. This exploratory study employed a mixed design, which
enabled comparisons among participants with varying job roles, work schedules, and
roster patterns. Over a period of approximately four weeks, each participant maintained
a sleep/wake diary and wore a sleep and activity tracker to record sleep quantity,
quality, and timing. In addition, daily subjective sleepiness was measured using the
Karolinska Sleepiness Scale.
Results: Data from 914 working days were analyzed. Key findings indicated significant differences
in sleep duration based on schedules and rosters. Participants working 12 hour split
shift schedules had significantly shorter sleep durations than participants with other
schedules and participants working 1 week on/1 week off rosters had significantly
longer sleep durations than participants with other rosters. The average sleep duration
was 7.1 hour, and sleep durations ≤ 5h were found in 7% of all working days. There
were no significant differences between job roles, shifts, or rosters in sleep quality
or max KSS rating during work shifts. One third of participants reported having to
fight sleepiness monthly, and 14% reported this 2–3 times a week or more often. Approximately
24% of KSS ratings were 7 or higher, with 27% of work shifts having KSS≥7. Sleepiness
increased with longer work hours across all groups, suggesting time on task related
fatigue.
Conclusion: Most participants managed to have 6–8 hour of sleep per night and few suffered from
chronic sleep restriction. However, a substantial proportion of work shifts was associated
with high levels of fatigue. Split shifts were associated with short sleep durations
and daytime sleepiness. There were relatively small differences between groups and
the overall picture is that fatigue is a workplace hazard for all job roles, rosters
and schedules. To mitigate the risk of sleepiness on duty, seafarers should be afforded
sufficient time for sleep between work shifts and the opportunity for rest breaks
during long shifts to mitigate task related fatigue. Support: The UK Department for
Transport funded this research.
