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The Health Effects of Rotating Shiftwork in the Oil Sector


Despite the improvements in safety since the advent of Process Safety Management regulations in 1992, human factors still play a large role in catastrophic accidents. Worker fatigue is a significant risk in the petroleum industry, where rotating shiftwork is relied upon to staff round the clock production. Using reports of work organization factors that contributed to fatigue from the listening sessions hosted by the California Interagency Taskforce on Refinery Safety in 2013, we developed a survey for rotating shiftworkers in the refining industry. We administered the survey among hourly shift workers in the oil sector represented by the United Steelworkers union. Collecting self-reported data on sleep, mental health, job stress, quality of life, and certain health outcomes associated with shift work, we explored associations between these outcomes and participants’ work history, current work schedules and staffing allocations. Our findings revealed that the 12-hour shift, initially intended as a compressed work week, currently provides limited recovery when rest breaks are interrupted with one or more overtime shifts per week. Sleep durations were also shortest on the 12-hour shift, and averaged more than an hour shorter than previous research on 8-hour rotating shift workers. Recent work schedules reported tended to comply with the American Petroleum Institute’s (API) recommended hours of service guidelines, but despite this, more than one half of our study participants reported having trouble staying awake during engaged activities (24% monthly and 27% weekly or more), and sleep disorder prevalence approached 80% in the study population. Those who exceeded the API hours of service guidelines reported greater job demands, shorter sleep durations, and more frequent drowsiness, indicating that they were at greatest risk for fatigue. Mandatory overtime was a stressor, associated with higher job stress, lower staffing coverage, and anxiety (but not additional hours worked). The impacts of mandatory overtime and on-call work were described further in the quality of life data, where participants described the difficulty of keeping personal commitments, resulting in family conflict, social isolation and neglected personal interests; and they expressed a desire for greater control over their time.

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