Sleep Quality in Shift Workers of Offshore Petroleum Industries

  • Khosro Sadeghniiat-Haghighi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Omid Aminian Center for Research on Occupational Diseases (CROD), Tehran University of Medical Sciences, Tehran, Iran
  • Areza Najafi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Ania Rahimi-Golkhandan Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Alireza Zahabi OccupationalOccupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran AND Department of Research and Technology, National Iranian Drilling Company, Ahvaz, Iran


Background and Objective: Shift work, especially at nights, has negative health outcomes for the workers, their families, and affiliated organizations. Working at night is associated with shortened and disturbed sleep, daytime sleepiness, fatigue, impaired performance, and increased risk of accidents. In this study, we aimed to evaluate sleep quality in different shift schedules of Iranian workers of offshore drilling rigs. Materials and Methods: One hundred and ninety two offshore workers of two oil rigs were enrolled in this crosssectional study. They were asked to fill out the validated and reliable Persian version of Pittsburg Sleep Quality Index (PSQI). Data regarding age, marital status, education level, smoking, shift work schedule, and body mass index (BMI) were recorded as well. Results: Mean age and mean work experience of the participants were 37.0 ± 9.3 and 10.0 ± 8.6 years, respectively. Fifty six participants (29.2%) were fixed day shift workers, 111 (57.8%) were swing shift workers (7 days/7 nights), 6 (3.1%) were fixed night shift workers, and 19 (9.9%) were standby shift workers. Mean PSQI score of all workers was 6.73 ± 3.61, and in 69% of the subjects, total score of PSQI was ≥ 5. Night shift workers had greater score of PSQI than other three groups of shift workers. Conclusion: This study showed that more than half of oil rig workers had poor sleep quality with the highest score among fixed night shift workers. This warrants comprehensive evaluation of the studied participants in terms of sleep disorders and related risk factors. Investigation of contributing occupational and environmental risk factors is also recommended.


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How to Cite
Sadeghniiat-Haghighi K, Aminian O, Najafi A, Rahimi-Golkhandan A, Zahabi A. Sleep Quality in Shift Workers of Offshore Petroleum Industries. JSS. 3(1-2):36-0.
Original Article(s)