O055 Fatigue risk in Search and Rescue operations: The challenge of sleep inertia and on-call work

Abstract Introduction Offshore Oil and Gas operations are normally supported by 24/7 Search and Rescue (SAR) services, which often involve fly-in-fly-out (FIFO) rosters. The current study followed SAR crew during two 21-day FIFO rosters to identify operational features that may increase fatigue risk. Methods Actigraphy was used to measure periods of sleep. At the start and end of each shift crew completed a 3-minute Psychomotor Vigilance Task and recorded ratings of fatigue and sleepiness. At the end of shifts workload ratings were made. Mixed model ANCOVAs were used to identify workplace factors associated with changes in fatigue, sleepiness and performance. Results Eighteen crew participated across 546 shifts. At the start of a shift, less prior sleep (p<.01) and less time awake (p<.001) were associated with greater fatigue and sleepiness. Fatigue and sleepiness were higher for shifts starting after 1500 (p<.01), whereas reaction time performance was slower for shifts starting before 0800 (p<.05). At the end of a shift, fatigue and sleepiness ratings were higher for longer shifts (p<.001), shifts with higher workload (p<.05), when crew had been awake longer (p<.05), or had been on-call the night prior (p<.05). Discussion A range of possible fatigue risks were identified. These included sleep inertia at the start of shifts, indicated by greater fatigue when time between waking and starting work was short. Being on call the night prior increased fatigue risk at the end of the next day’s shift. Through understanding where the fatigue risks are, an organization can ensure mitigations are appropriate.