Fatigue onboard vessels

Safety

Published: 29 August 2025

Image credit to: Kardasov Films / Shutterstock.com

Purpose

This advice aims to raise awareness about the risks associated with fatigue onboard vessels and outline preventive measures to safeguard crew health, operational safety, and vessel integrity.

Fatigue – A critical safety concern

Fatigue is a physical and mental condition resulting from prolonged exertion, sleep loss, or disruption of circadian rhythms. It significantly affects performance, decision-making, and alertness and increases the likelihood of accidents.

Common causes onboard include

  • Long working hours without adequate rest
  • Irregular sleep schedules
  • High workloads or understaffing
  • Stress from isolation or demanding conditions
  • Poor sleeping environments

Consequences of fatigue

  • Diminished concentration and reaction time
  • Impaired judgment and decision-making
  • Health problems such as insomnia, anxiety, and chronic fatigue
  • Higher likelihood of marine incidents and near-misses

Preventive measures

To promote a safe and healthy working environment, consider implementing the following:

  • Ensure adherence to IMO and flag state rest hour requirements. Schedule duties to avoid exceeding regulatory limits and allow compensatory rest when exceptions occur.
  • Fatigue awareness training: Educate crew on recognising fatigue symptoms and reporting concerns.
  • Encourage open communication: Foster a culture where crew members feel safe to report fatigue without fear of reprisal.
  • Improve sleeping conditions: Maintain quiet, well-ventilated cabins with comfortable bedding.
  • Workload management: Distribute tasks evenly and avoid excessive overtime.
  • Electronic monitoring: Use digital systems to log rest hours and detect non-compliance.
  • Fatigue risk management systems (FRMS): Integrate medical, psychological, and operational factors.

Regulatory framework

TCW Convention (2010 Amendments)

  • Minimum rest hours: 10 hours in any 24-hour period; 77 hours in any 7-day period.
  • Rest periods: Must be divided into no more than two periods, one of which must be at least 6 hours.
  • Recordkeeping: Accurate work/rest hours logs must be maintained and available for inspection.

Maritime Labour Convention (MLC, 2006)

  • Maximum work hours: 14 hours in any 24-hour period any 24 hours; 72 hours in any 7-day period.
  • Rest requirements: Align with STCW but emphasise transparency and documentation.
  • Compliance tools: Ships must carry a Maritime Labour Certificate and Declaration of Maritime Labour Compliance (DMLC).

International Safety Management (ISM) Code

  • Safety Management Systems (SMS): Must include fatigue risk management procedures.
  • Leadership Responsibility: Masters and the company management are accountable for monitoring fatigue and ensuring compliance.
  • ISM Audits: Non-compliance with fatigue protocols may result in deficiencies during audits or Port State Control inspections.

Leadership and accountability

Shipowners, operators, and masters must:

  • Actively monitor crew wellbeing, respect rest hours, and intervene when fatigue is suspected. Proactive leadership ensures compliance and cultivates a culture of care.
  • Ensure compliance with STCW, MLC, and ISM fatigue provisions.
  • Maintain transparent records and support crew in reporting violations.
  • Foster a safety culture that prioritises rest and wellbeing.