Original Article

Sleep Quality in Shift Workers of Offshore Petroleum Industries


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.

Akerstedt T. Shift work and disturbed sleep/wakefulness. Occupational Medicine. 2003; 53(2):89-94.

Torsvall L, Akerstedt T, Gillander K, et al. Sleep on the night shift: 24‐hour EEG monitoring of spontaneous sleep/wake behavior. Psychophysiology. 1989; 26(3):352-8.

Mitler MM, Miller JC, Lipsitz JJ, et al. The sleep of long-haul truck drivers. New England Journal of Medicine. 1997; 337(11):755-62.

Callister R, Suwarno NO, Seals DR. Sympathetic activity is influenced by task difficulty and stress perception during mental challenge in humans. The Journal of Physiology. 1992; 454(1):373-87.

Waage S, Moen BE, Pallesen S, et al. Shift work disorder among oil rig workers in the North Sea. Sleep. 2009; 32(4):558.

Harris A, Waage S, Ursin H, et al. Cortisol, reaction time test and health among offshore shift workers. Psychoneuroendocrinology. 2010; 35:1339–47.

Hope S, Øverland S, Brun W, et al. Associations between sleep, risk and safety climate: a study of offshore personnel on the Norwegian continental shelf. Saf Sci. 2010; 48: 469–77.

Parkes KR. Mental health in the oil industry: a comparative study of onshore and offshore employees. Psychol Med. 1992 ; 22: 997–1009.

Buysse DJ, Reynolds CF , Monk TH, et al. The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res.1989; 28(2):193-213.

Axelsson J, Akerstedt T, Kecklund G, et al. Tolerance to shift work—how does it relate to sleep and wakefulness? International archives of occupational and environmental health. 2004; 77(2):121-9.

Harrington JM. Health effects of shift work and extended hours of work. Occupational and Environmental medicine. 2001; 58(1):68-72.

Bjorvatn B, Stangenes K, Oyane N, et al. Subjective and objective measures of adaptation and readaptation to night work on an oil rig in the North Sea. Sleep. 2006;29(6):821-9.

Waage S, Harris A, Pallesen S, et al. Subjective and objective sleepiness among oil rig workers during three different shift schedules. Sleep Medicine. 2012; 13(1): 64-72.

Gibbs M, Hampton S, Morgan L, et al. Adaptation of the circadian rhythm of 6sulphatoxymelatonin to a shift schedule of seven nights followed by seven days in offshore oil installation workers. Neuroscience letters. 2002; 325(2):91-4.

Parkes KR. Age, smoking, and negative affectivity as predictors of sleep patterns among shift workers in two environments. Journal of Occupational Health Psychology 2002; 7(2):156-173.

Fossum IM, Bjorvatn B , et al. Effects of Shift and Night Work in the Offshore Petroleum Industry: A Systematic Review. Ind Health. 2013; 51(5): 530–544.

Zohreh Yazdi, Khosro Sadeghniiat-Haghighi, Ziba Loukzadeh, et al. Prevalence of Sleep Disorders and Their Impacts on Occupational Performance: A Comparison between Shift Workers and Nonshift Workers, Sleep Disorders, vol. 2014, Article ID 870320, 5 pages, 2014. doi:10.1155/2014/870320.

Ohayon MM, Chen MC, Bixler E, Dauvilliers Y, Gozal D, Plazzi G, Vitiello MV, Paskow M, Roach A, Hirshkowitz M. A provisional tool for the measurement of sleep satisfaction. Sleep health. 2018 Feb 1;4(1):6-12.

IssueVol 3 No 1-2 (2018): Winter-Spring QRcode
SectionOriginal Article(s)
Oil and gas industry Shift work schedule Sleep

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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. J Sleep Sci. 2019;3(1-2):36-40.