Work-leave rotation pattern and incidence of offshore workplace injury

Studies on work-leave rotation pattern and work place injuries among offshore oil and gas workers have been few and limited to a 2- or 3-week rotation schedule.

To examine incidence of workplace injury in relation to the duration of time into work rotation for extended work schedules up to 24 weeks.

Six-year injury data on four offshore installations were extracted. Data were analysed for incidence of injury over time and relative risk using linear trend lines and regression.

In total, 311 injuries for 1302 workers were analysed, 39% with rotation schedule of 4 weeks work and 4 weeks rest, 27% 8 weeks work and 4 weeks rest, 23% 16 weeks work and 4 weeks rest and 10% 24 weeks work and 4 weeks rest. Incidence of injury decreased as duration of time into the work rotation increased, corrected for exposure, and this was statistically significant for all rotations in first 4 weeks (P < 0.01). Negative correlation between time offshore and injury was observed in all schedules and consistent for age groups, categories of work, shifts and severity of injury. There was no difference in relative risk of injuries between the four schedules, when corrected for exposure and occupational risk of injury.

These results are at variance with previous studies, although no prior study has looked beyond 3-week rotation schedule. Longer offshore schedules are safely possible and this could help decrease manpower and logistics costs for oil and gas companies coping with unprecedented low oil prices.