Module 3 - Fatigue and the seafarer

  1. Module 3 contains practical information intended for the seafarer (master, officers, ratings and all other shipboard personnel) working on ships. Prior to reviewing this module, it is strongly recommended that all seafarers become familiar with module 1 (Fatigue) first. Management-level seafarers (master and officers) should also become familiar with module 2 (Fatigue and the company).

  2. Although the company is primarily responsible for creating a work and living environment that minimizes fatigue-related risks, seafarers are responsible for ensuring that time available for rest and sleep is used appropriately and that their behaviour does not create or increase risk.

  3. The maritime industry operates a variety of work schedules in a wide range of operational environments, which means that at some point seafarers are likely to experience fatigue. Fatigue affects all individuals, regardless of skill, rank, knowledge or training.

    How to recognize fatigue (signs/symptoms)?

  4. Fatigued individuals are poor judges of their own level of fatigue and performance because fatigue affects their ability to make judgements or solve complex problems.

  5. Fatigue-related signs and symptoms are often divided into three categories: cognitive, physical and behavioural (see table 1 in module 1). Seafarers may recognize some of these in others and, with time, lessons can be learnt to identify some within themselves. These signs and symptoms of fatigue may be used to identify an individual's level of alertness.

  6. Some of the more apparent signs and symptoms include:

    .1 cognitive:
         .1 focuses on a trivial problem, neglecting more important ones;
         .2 slow or no response to normal, abnormal or emergency situations;
         .3 lapses of attention;
         .4 poor judgement of distance, speed, time, etc.;
         .5 forgets to complete a task or part of a task; and
         .6 difficulty in concentrating and thinking clearly.

    .2 physical:
         .1 inability to stay awake (an example is head nodding or falling asleep  involuntarily);
         .2 difficulty with hand-eye coordination skills (such as switch selection);
         .3 speech difficulties (it may be slurred, slowed or garbled);
         .4 increased frequency of dropping objects like tools or parts; and
         .5 digestion problems;

    .3 behavioural:
         .1 decreased tolerance and/or anti-social behaviour;
         .2 irregular/atypical mood changes (examples are irritability, tiredness and/or depression)
         .3 ignores normal checks and/or procedures; and
         .4 increasing omissions, mistakes, and/or carelessness.

  7. Long-term effects of sleep loss may lead to cardiovascular diseases, gastrointestinal diseases, mental health problems and stress.

  8. The more signs and symptoms seafarers observe in others and/or experience themselves, the more likely it is that alertness is significantly reduced. Fatigue is not the only cause of such symptoms, but when several occur together, it is likely to indicate fatigue-related impairment. It is important that seafarers notify crewmates and supervisors when they recognize that they or other crew members are fatigued. It is important to have open communication between seafarers, their crewmates and their supervisors regarding fatigue prevention and detection. The company's fatigue risk mitigation strategy should allow for open communication and reporting between seafarers, their supervisors and management levels regarding fatigue prevention and detection, and should prohibit any action directed against a seafarer for such communications or reports.

    What can seafarers do to help reduce and manage the risk of fatigue on ships?

  9. Obtain adequate sleep: The most effective strategy to fight fatigue is to obtain adequate quality, quantity and continuity of sleep. As indicated in module 2, the company should provide seafarers with an adequate sleep opportunity for recovery. Insufficient sleep over several consecutive days will impair alertness; only sleep can maintain or restore performance levels.

  10. Sleep is most valuable if obtained in a single block. While a short sleep or nap can provide a powerful boost in alertness, it does not eliminate the need for longer periods of sleep.

  11. There may be instances when seafarers may not obtain adequate sleep, even though they are provided with adequate sleep opportunity. The items mentioned below can all affect the quantity and quality of sleep obtained:

    .1 seafarers are working during the night and may simply be unable to sleep during the day;

    .2 seafarers' sleep may have been interrupted by colleagues, unexpected events or operational demands;

    .3 seafarers may suffer from a sleep disorder, or other medical or physical problem that keeps them awake;

    .4 emotional stress due to personal circumstances including family problems at home;

    .5 inability to get to sleep due to concerns about work or other worries;

    .6 the sleeping environment (comfort, noise, darkness, ship motion, privacy) may not allow for adequate sleep;

    .7 the type of food consumed;

    .8 medication or use of prescribed/over-the-counter/natural remedies;

    .9 consumption of stimulants, i.e. caffeine, amphetamines, energy drinks;

    .10 consumption of alcohol;

    .11 use of electronic devices which emit blue light (e.g. smartphones, tablets, computer screens) have been shown to adversely affect the onset of sleep;

    .12 adjusting to a new watch schedule and recovering from jet lag; and

    .13 social activities or high excitement just before sleep period.

  12. Regardless of the circumstances causing insufficient or poor quality sleep, these should preferably be identified through proactive measures and treated as a potential shipboard hazard.

  13. The company should have processes in place to provide seafarers with the opportunity to report situations when they have been unable to obtain adequate sleep or feel at risk of making fatigue-related errors, specifically if conducting safety critical tasks, without fear of reprisal. This can be as simple as verbally reporting to supervisors, management levels and/or the ship's safety committee.

  14. Some general guidance on developing good sleep habits is given below:

    .1 if possible, develop consistent sleep times, i.e. try to go to bed at the same time every day;

    .2 develop and follow a pre-sleep routine to promote sleep at bedtime, e.g. a warm shower, reading calming material or just making a ritual of pre-bed preparation;

    .3 get sufficient sleep, especially before a period when time for adequate sleep may not be available;

    .4 avoid stimulating activities prior to sleep such as exercise, television and movies;

    .5 make the sleep environment conducive to sleep (a dark, quiet and cool environment and a comfortable bed encourages sleep); a white noise generator or earplugs can be of use if you find them helpful; block out as much light as possible; this might involve the use of blackout curtains, roller shutters, heavy blinds or an inexpensive option such as black plastic; a sleep mask can also be used;

    .6 as much as possible, ensure there will be no interruption during your period of sleep;

    .7 avoid alcohol, caffeine and other stimulants prior to sleep (keep in mind that coffee, tea, colas, chocolate and some medications, including cold remedies and aspirin, contain alcohol and/or caffeine); avoid caffeine at least four hours before bedtime

    .8 relaxation techniques, such as meditation, may help;

    .9 do not nap if you have difficulty sleeping during your normal sleep period;

    .10 avoid eating right before sleeping; and

    .11 limit the use of electronic devices that emit blue light prior to bedtime.

    Maintain fitness for duty

  15. Ensuring that seafarers are fit for duty and able to maintain safe levels of alertness and performance is important. Taking responsibility for seafarers' duty schedules and rest periods and providing feedback to their supervisors, management levels and the company is important to ensure that seafarers are provided with the best possible opportunity to maintain fitness for duty.

  16. In some cases, monitoring and assessing seafarers' level of fatigue prior to their duty schedule can be helpful in ensuring they are able to perform tasks safely. There are a number of tools that can be used to assess how seafarers feel prior to and during their duty period, such as self-monitoring or fatigue assessment tools. It is important to report (to seafarers' supervisors and/or management levels) any instances in which seafarers feel that safety could have been or will be compromised due to fatigue impairment in either themselves or their peers.

  17. Some general guidance that may help seafarers maintain fitness for duty is given below:

    .1 take strategic naps (the most effective length of time for a nap is about 20 minutes);

    .2 take advantage of scheduled breaks;

    .3 whenever possible, monitor and effectively manage sleep;

    .4 whenever possible, maintain and monitor fitness for duty including medical fitness;

    .5 report any fatigue impairment in yourself and in others that may have the potential of affecting ship safety;

    .6 record and report actual hours of work and rest as required by the MLC and the STCW Convention;

    .7 eat regular, well-balanced meals;

    .8 exercise regularly; and

    .9 limit the use of medications that may affect levels of alertness and performance, including seasickness medications (if such medications are used, shipboard supervisor should be informed accordingly).

  18. A number of countermeasures have been identified as potentially providing some relief in managing fatigue. It must be emphasized that these countermeasures will not restore an individual's state of alertness; they only provide short-term relief and may, in fact, simply mask the symptoms temporarily. At some stage, sleep must be obtained for physical and mental recovery to occur. The following list captures some of these short-term countermeasures:

    .1 Short rest breaks within duty periods
    Rest, apart from sleep, can be provided in the form of short breaks or changes in activities during the duty period. Rest breaks may be helpful if performance is to be maintained over long periods of time. Factors influencing the need for rest are the length and intensity of the activities prior to a break or a change in activity, the length of the break, or the nature or change of the new activity. It is recognized that in a shipboard environment this may not always be feasible; however, short breaks should be planned into the duty period as much as possible.

    .2 Strategic napping
    A short sleep or nap can provide a powerful boost to alertness. Research has identified strategic napping as a short-term relief technique to help maintain performance levels during long periods of wakefulness. Naps as short as 10 to 15 minutes are known to deliver measurable benefits. Naps are helpful in maintaining performance if sufficient longer sleep is occasionally missed. The most effective length of time for a nap is about 20 minutes. It is recommended that seafarers take naps in the way that they believe best suits them. Napping should be encouraged to be a planned activity of fatigue management and prevention. This means that if seafarers have the opportunity to nap they should take it. However, there are some drawbacks associated with napping. One potential drawback is that naps longer than 30 minutes will cause sleep inertia, where situational awareness is impaired (grogginess and/or disorientation for up to 20 minutes after waking). A second potential drawback is that the nap may disrupt later sleeping periods (a person may not be tired when the time comes for an extended period of sleep).

    .3 Caffeine
    Another popular fatigue countermeasure is the strategic use of caffeine (encountered in coffee and tea, and to a lesser extent in colas and chocolate) as a stimulant. Caffeine can improve alertness temporarily but it is not a substitute for adequate sleep and rest. It takes caffeine 15 to 30 minutes to take effect and caffeine levels drop by half every five or six hours. Its effects can last long after consumption and may interfere with needed sleep. It is important to consider, however, that there are individual differences in terms of how the effects of caffeine, tolerance and withdrawal develop. Caffeine should be avoided before bedtime. In addition, regular usage over time reduces its value as a stimulant and may increase tiredness and reduce ability to sleep. Caffeine consumption can also cause other side effects such as hypertension, headaches, mood swings and anxiety.

    .4 Nutrition and hydration
    Adequate nutrition and hydration is important for managing and preventing fatigue. Ideally, one should have a balanced diet, eat regularly, have healthy snacks, plan meals, drink water regularly and avoid meals just before bedtime (as eating just before bedtime results in slower digestion). The recommended daily intake of water is two litres or eight glasses. Monitoring one's fluid intake helps to optimize alertness and wakefulness.

    .5 Environment (light, temperature, humidity and sound)
    Bright lights, cool dry air, obtrusive or loud music or other annoying irregular sounds may temporarily increase alertness.

    .6 Physical activity
    Physical well-being has a number of key components, notably exercise, diet, hydration and sleep. Any type of physical activity helps to maintain alertness; running, walking, stretching or even chewing gum can stimulate the level of alertness. Exercise can also improve sleep. Proper physical self-care results in a range of positive outcomes including reserves of energy during the duty period, consistent and restful sleep patterns, proper concentration spans and a satisfying sense of feeling healthy. The benefits of regular exercise include improved mood, better stress coping, and enhanced self-esteem and well-being.

    .7 Social interaction
    Social interaction (conversation) can help one stay awake. However, the conversation should be interactive to be effective.

    .8 Job rotation when practicable
    Changing the order of activities can be beneficial in breaking up job monotony. Mixing tasks requiring high physical or mental work with low-demand tasks can be beneficial.

  19. When feeling fatigued, seafarers may engage in individual fatigue countermeasures, such as walking around, using caffeine or stimulants, to reduce the likelihood of fatigue-related errors. However, there may be instances when high levels of fatigue cannot be mitigated by individual countermeasures. Hence, prompt, consistent and appropriate action is required (by the management-level seafarers through company support) whenever a seafarer is potentially not fit for duty. This may include the need for additional actions, such as task rotation and additional supporting resources, for managing fatigue-related risks. The aim should be to maintain and promote safety.

    What are the seafarer's responsibilities in fatigue risk management on ships?

  20. The particular nature of fatigue as a safety hazard makes managing shipboard fatigue and associated risks the shared responsibility of the company and the seafarer. As highlighted in other sections, there are a number of measures that can be taken to mitigate the risk of fatigue. Many of the measures are unfortunately beyond a single person's ability to influence, such as voyage scheduling, ship design and work scheduling.

  21. Seafarer responsibilities include:

    .1 doing their best to commence duty schedule in a fit state to work the expected duty length and perform assigned shipboard work safely;

    .2 monitoring and effectively managing hours of sleep;

    .3 reporting fatigue-related hazards that affect safety;

    .4 maintaining appropriate communication about safety;

    .5 being aware of fatigue and how to counter its effects; and

    .6 using available rest periods appropriately, in addition to using personal fatigue mitigation strategies.

  22. Seafarers are responsible for monitoring and seeking appropriate treatments for any health concerns that may impact their fitness for duty. Seafarers' well-being can be affected by a variety of factors including health conditions, genetic predispositions, nutrition, hydration and sleep difficulties. A wide range of sleep difficulties can affect fatigue, circadian rhythm, sleep duration and sleep quality. This includes a diversity of sleep disorders as indicated in module 1.

  23. Module 2 provides recommended strategies for the company to manage the risks of fatigue at sea. Some important aspects related to company responsibility include:

    .1 developing policies and practices within the ship's safety management system to manage fatigue-related risks;

    .2 developing work schedules that prevent high levels of fatigue during duty periods;

    .3 developing work schedules that allow for adequate rest and recovery periods between duty schedules (if possible allow for an anchor sleep period of seven to eight hours);

    .4 implementing appropriate and safe duty/watch periods taking into account circadian rhythms;

    .5 providing an adequate sleep environment on the ship;

    .6 ensuring all seafarers are trained and aware of the causes and consequences of fatigue;

    .7 promoting a safety reporting culture with open communication and no fear of reprisal; and

    .8 continuously assessing, controlling, monitoring and evaluating fatigue-related hazards.

    What can management-level seafarers do to reduce and manage the risk of seafarer fatigue on ships?

  24. The following provides a recommended list of important fatigue management strategies in controlling and reducing the risk of fatigue on board ships, and are within the management-level seafarer's ability to influence and/or implement:

    .1 ensuring, as a minimum, compliance with minimum hours of rest and/or maximum hours of work;

    .2 using rested personnel to cover for those travelling long hours to join the ship, e.g. allowing proper time to overcome fatigue and become familiarized with the ship;

    .3 managing the amount of time seafarers need to spend performing physically and mentally demanding work for a sustained period of time (e.g. tank cleaning, navigation through congested waters);

    .4 ensuring nutritious food options are served on board and seafarers have continuous access to drinking water;

    .5 providing night-time personnel with appropriate meal choices;

    .6 maintaining interaction between shore management and ship management with respect to fatigue awareness and preventive measures on board the ships;

    .7 creating an open communication environment, by making it clear to the crew members that it is important to inform supervisors when fatigue is impairing their performance or that of others and ensuring that there will be no recriminations for such reports;

    .8 ensuring that selected seafarers can do the job for which they are assigned to prevent the potential for fatigue in other crew members;

    .9 improving shipboard conditions to ensure that when there is an opportunity to sleep, crew members can take advantage of it without interruptions, e.g. by scheduling drills and routine maintenance functions in a manner that minimizes the disturbance of rest/sleep periods; all relevant seafarers should be aware of these protected sleep opportunities;

    .10 establishing onboard management techniques when scheduling shipboard work and rest periods and when scheduling work practices and assignment of duties in a more efficient manner;

    .11 if practicable, assigning work by mixing up tasks to break monotony and to combine work requiring high physical or mental demand with low-demand tasks (job rotation);

    .12 avoiding scheduling potentially hazardous tasks during the circadian lows of the seafarers involved, when practicable;

    .13 providing support for seafarers to recognize and deal with the effects of fatigue including onboard training, if provided;

    .14 emphasizing the seafarer's responsibility to sleep during rest periods to ensure that adequate sleep is obtained;

    .15 taking time to monitor that all personnel are getting adequate sleep;

    .16 ensuring that shipboard conditions, within the seafarer's ability to influence, are maintained in a good state, e.g. maintaining the heating, ventilation and air conditioning on schedule, light bulbs are replaced and sources of unusual noise are taken care of at the first opportunity;

    .17 reappraising work patterns and areas of responsibility on board to establish the most efficient utilization of resources (such as sharing the long cargo operations between all the deck officers instead of the traditional pattern and utilizing rested personnel to cover for those who have travelled long hours to join the ship);

    .18 promoting supportive relationships on board (good morale) and dealing with interpersonal conflict between seafarers;

    .19 establishing shipboard practices for dealing with fatigue incidents and learning from them, e.g. as part of the safety meeting;

    .20 increasing awareness of the benefits of a healthy lifestyle, e.g. exercise, relaxation, proper nutrition;

    .21 timely coordination of scheduled activities between the company, management-level seafarers and other stakeholders; and

    .22 allowing time for communication at watch/work handovers.

    What rules and regulations are in place to help manage fatigue?

  25. Reference is made to the instruments mentioned in module 1.

  26. In addition to the international standards, company and flag Administration policies, which may be more stringent in some cases, should be followed on board all ships.


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