Shift schedules on North Sea oil/gas installations: A systematic review of their impact on performance, safety and health

Continuous production processes on North Sea installations necessitate extended work schedules; 2-week offshore tours (alternating with shore breaks), 12 h shifts and rapid day/night shift changes are inherent features of offshore work. These intensive rosters, worked in a demanding physical and psychosocial environment, are potential sources of fatigue and impaired performance among offshore personnel. This article focuses on offshore working time arrangements, and presents a systematic review of studies which examine offshore day/night shift patterns in relation to operational safety and individual health risks. Of the 53 studies retrieved, 24 met the review criteria.Field study findings are generally consistent in showing that sleep, alertness and performance are relatively stable across day-shift tours; initial night shifts are adversely affected by circadian disruption, but full physiological and psychological adaptation occurs within 5–6 days; re-adaptation to day shifts is slower, and varies widely across individuals; the offshore environment is conducive to night-shift adaptation, but interventions to facilitate re-adaptation have proved only modestly effective. Analyses of survey data and accident/sickness records identify offshore night work as a risk factor for impaired sleep, health problems, and injuries, but little is known about the long-term health effects of different offshore shift rotations.In conclusion, research methodology and findings, and working time issues of current concern to the offshore oil/gas industry, are discussed. Aspects of offshore work schedules that have been not been widely studied (e.g. overtime, irregular work patterns) are also highlighted, and research areas that would merit further attention are noted.

► Offshore rosters (14 days/12 h shifts/day–night work) impact on safety/health risks.
► Day-shift tours: stable sleep/alertness/performance, no cumulative fatigue effects.
► Full circadian adaptation offshore takes 5–6 days; high risks of initial night shifts.
► Mid-tour day/night shift changes disrupt adaptation, impair sleep, increase risks.
► Alternate 14-day/14-night tours reduce health/safety risks but disliked by workers.