Seafarer fatigue: a review of risk factors, consequences for seafarers' health and safety and options for mitigation

Background: The consequences of fatigue for the health and safety of seafarers has caused concern in the industry and among academics, and indicates the importance of further research into risk factors and preventive interventions at sea. This review gives an overview of the key issues relating to seafarer fatigue. Materials and methods: A literature study was conducted aiming to collect publications that address risk factors for fatigue, short-term and long-term consequences for health and safety, and options for fatigue mitigation at sea. Due to the limited number of publications that deals with seafarers, experiences from other populations sharing the same exposures (e.g. shift work) were also included when appropriate. Results: Work at sea involves multiple risk factors for fatigue, which in addition to acute effects (e.g., impaired cognition, accidents) contributes through autonomic, immunologic and metabolic pathways to the development of chronic diseases that are particularly prevalent in seafarers. Conclusions: Taking into account the frequency of seafarer fatigue and the severity of its consequences, one should look into the efficacy of the current legislative framework and the industry's compliance, the manning of the international merchant fleet, and optimised working, living and sleeping conditions at sea. Considering circumstances at sea, e.g. working in shifts and crossing time zones, that cannot be altered, further assessment of the potentials of preventive interventions including fatigue prediction tools and individual fatigue mitigation management systems is recommended.