Module 2 - Fatigue and the company

  1. Module 2 contains guidance for the company in assessing, mitigating and managing the risk of fatigue in operational environments.

    Is fatigue an important issue in shipboard operations?

  2. Fatigue has been recognized as an important occupational health and safety issue for seafarers. Fatigue has the potential to greatly increase the risk of incidents and injuries in the work place. It disrupts circadian rhythms and results in digestive problems, confusion, lethargy, respiratory problems, depression and irritability. Fatigue adversely affects seafarer performance. It diminishes attentiveness and concentration, slows physical and mental reflexes and impairs rational decision-making capability.

  3. Research has established a clear link between fatigue and accidents at sea. Clearly, addressing the issue of fatigue should have a positive effect on personnel safety and has the potential to cut costs for the company by reducing injury and physical damage to high-value assets and the environment.

  4. Fatigue poses a risk to any position on board, but especially those that have critical safety and security responsibilities. Should an individual fail to carry out an allotted task due to fatigue, the crew runs the risk of a safety or security incident. Any risk management strategy must focus on mitigating the potential for such hazards to arise by addressing the causes of fatigue. Systems and work procedures should be critically examined to engineer out design deficiencies that could contribute to fatigue. The company should provide an adequate level of support for managing the risks of fatigue at both the organizational and operational levels.

    What elements of fatigue can the company influence?

  5. While it is not possible for the company to regulate and oversee the sleeping habits of every seafarer on every ship, it is within its capability to mitigate the risks of fatigue through ship design, operational and manning policies. The Principles of minimum safe manning (resolution A.1047(27)) provides for an assessment of the tasks, duties and responsibilities of the ship's complement to ensure that manning levels are adequate at all times to meet all conditions and requirements including meeting peak workload situations and emergency conditions. Hours of rest are presently controlled by a prescriptive formula set out in chapter VIII of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) 1978, as amended. Managers should be aware (when applying these hours of rest) that considering the effects of circadian rhythm and sleep debt is important for ensuring that rest periods are of high quality. It also cannot be too highly stressed that rest means rest, not substituting a different form of work. This should be supported by appropriate manning, resources, processes and policies, so that fatigue risks can be managed in a way that supports safe, compliant and productive operations. Importantly, fatigue risk control measures forming part of the company support should:

    .1 identify and assess fatigue risks;

    .2 assess operational workload requirements in accordance with the Principles of minimum safe manning (resolution A.1047(27));

    .3 ensure that manning and resources are adequate and available for assessed workload requirements and to conduct all ship operations safely;

    .4 ensure company-wide awareness of the risk of fatigue; and

    .5 ensure a healthy shipboard environment.

  6. Figure 1 below provides a framework to assess the hazards associated with fatigue and different strategies to mitigate the risk of fatigue.

    Figur 1 Framework to mitigate the risk of fatigue                Figur 1: Framework to mitigate the risk of fatigue

  7. Companies' records of hours of work and rest are generally assessed against regulatory requirements. Planning tools are available that take into account the circadian rhythm. The use of such planning tools may assist companies in doing the following:

    .1 Analyse planned work routines to ascertain the risk of fatigue.

    .2 Monitor work hours on board the ship to determine whether or not the risk of fatigue is increasing as a result of the work arrangements or from any variations that may have occurred.

    .3 Analyse and compare information related to hours of work to determine the effectiveness of employed routines, compared to other alternatives.

  8. It is important that companies adopt a fatigue mitigation and control strategy that is tailored to the individual operational requirements.

    How can the company ensure that fatigue prevention is practised on board?

  9. The company should consider the following:

    .1 ISM Code requirements for clear, concise guidance on operational procedures on board;

    .2 ensure adequate resources, including manning levels;

    .3 promote a safety reporting culture with open communication and no fear of reprisal;

    .4 the need for joining seafarers to be adequately rested before assuming duties;

    .5 schedule time for proper handover on crew change;

    .6 voyage length, time in port, length of service and leave ratios;

    .7 multicultural issues; language barriers, social, cultural and religious isolation;

    .8 interpersonal relationships, stress, loneliness, boredom, social deprivation and increased workload as a result of small crew numbers;

    .9 provision for shore leave and onboard recreation, family communication;

    .10 watchkeeping arrangements;

    .11 job rotation, if practicable;

    .12 adequate sleeping berths and accommodation;

    .13 adequate quality and quantity of food for proper nutrition;

    .14 read other modules of these guidelines for additional potential managerial mitigation tools; and

    .15 modification of present ship design or future designs, if necessary.

  10. Fatigue training and awareness are essential components. The company should ensure all personnel have appropriate training. This includes shore-based personnel whose decisions may impact on the management of fatigue (such as those involved in resource planning, including ship manning levels, and duty scheduling decisions) and fatigue-related processes. This is important, as their decisions potentially affect fatigue levels of seafarers and consequently shipboard safety.

  11. Initial fatigue-related training should establish a common level of understanding among seafarers and shore-based personnel about the dynamics of sleep loss and recovery, the effects of the body clock on circadian rhythms, the influence of workload, and the ways in which these factors interact with operational demands to produce fatigue (covered in module 1). In addition, it is useful for all seafarers to have information on how to manage their personal fatigue and sleep issues (covered in module 3).

  12. This process, as with any other training, should be ongoing in nature. Hence, training should be conducted on an initial and recurrent basis. The interval between training should be determined by the company, given their operational characteristics and training needs analysis.

  13. Promoting a safety reporting culture is necessary. The company should ensure that processes are in place to provide seafarers with the opportunity to report situations when the seafarer has been unable to obtain adequate sleep or feels at risk of making fatigue-related errors, specifically if conducting safety critical tasks. This process should allow for open communication and reporting between seafarers, their supervisors and the company, and should prohibit any action directed against a seafarer for such communications or reports.

    Adequate resources (including ship manning levels)

  14. Adequate resources, including manning, is one of the primary determinants of seafarers' duty hours, workload, duty scheduling, average time off duty, and other key factors that can have an influence or elevate fatigue. The company should ensure that adequate resources are available with a need to proportionally balance varying work and task demands and deal with unexpected surge to reduce the risk of fatigue across shipboard operations.

  15. Manning levels should match the operational workload on board the ships and this workload should be managed efficiently. Operational workload is determined through an assessment by the company.

  16. Although the master is responsible for managing the ship and its crew, the company should ensure that the master is adequately supported and resourced to conduct shipboard duties and operations safely and effectively.

  17. Effective operational planning is critical to ensuring adequate resources, including manning, are available at all times so that operational and other demands placed on the ship and its crew can be managed safely and effectively. Planning should account for:

    .1 varying work and task demands within and across days, e.g. amount of time the ship is travelling through confined and congested waters and less confined open waters;

    .2 trading patterns, i.e. number of port calls – the more port calls the higher the workload;

    .3 planning for disturbances, such as weather, ship movement in port, port entry and exit delays and port surveys and inspections;

    .4 ensuring adequate manning is available to cover planned and unplanned aspects such as training, illnesses, injuries and sickness; and

    .5 ensuring company commercial obligations or interests do not impinge on or affect safety in any way.

  18. The company should consider strategies to deal with periods of high workload and to manage this accordingly. Appropriate strategies may include the following:

    .1 The allocation of crew numbers to peak times and demands is a fundamental factor in minimizing the exposure to risks associated with extended duty hours. Numbers and types of seafarers should be scheduled based on predictable operational demands to account for daily, weekly and monthly operational trends.

    .2 Ensure the master is well resourced and supported to carry out all shipboard tasks safely and to allow for unexpected surge and overriding operational conditions.

    .3 Ensure there are adequate resources, including manning, available to complete shipboard tasks safely without placing excessive demands on seafarers.

    .4 Augment with shore-based support or additional rest when the ship is in port, such as during loading and unloading and port inspections, to ensure shipboard crew obtain adequate time off for rest and sleep and are fit for duty when the ship leaves port.

    .5 Provide shipboard administrative support or a means for relieving the burden associated with paperwork and related administrative tasks.

    .6 Where practicable, provide remote support to shipboard crew in areas such as paperwork, loading/unloading calculations.

    .7 Utilize other crewing concepts, such as the use of port captains and/or shore-based crew.

    .8 Plan arrival and departures (tides in ports, delays due to weather, pilotage boarding, etc.) to take into account adequate sleep and rest.

  19. An important aspect that needs to be mentioned is that of "overriding operational conditions". In accordance with section B-VIII/1 of the STCW Code "overriding operational conditions" should be construed to mean only essential shipboard work which cannot be delayed for safety, security or environmental reasons or which could not reasonably have been anticipated at the commencement of the voyage. This means that they should not be occurring on a regular basis. Planning, using risk assessment tools and operational experience, can foresee these potential disruptions or delays, e.g. weather, port inspections, traffic congestion during departure/arrivals and illness of seafarers.

    Healthy shipboard environment

  20. Seafarers are required not only to work but also to live on board a ship. Hence, ensuring a healthy shipboard environment is crucial to minimizing the risks of fatigue. The most important aspects should include:

    .1 Healthy eating: healthy nutritious food is available and served on board and crew afforded unlimited access to drinking water.

    .2 Healthy sleep: the shipboard sleeping environment should provide for comfortable and good quality sleep (bedding, pillows, mattresses, adequate light management, etc.).

    .3 Exercise: adequate exercise facilities are provided (such as well-designed and equipped training facilities and outside spaces), to ensure seafarers can maintain a healthy lifestyle on board.

    .4 Stress: adequate shipboard measures are in place to recognize and ensure adequate support to seafarers suffering from stress.

  21. Furthermore, initial ship design plays a part in ensuring a healthy operational environment (see module 5).

    Adequate sleep opportunity

  22. Effective fatigue management is predominantly about ensuring that seafarers are provided with adequate sleep opportunity.

  23. It is not correct to assume that a given rest period from duty will provide a given level of sleep and hence recovery. The length of the rest period is only one key factor. The relationship between the recovery value of off-duty periods and the actual amount of sleep obtained in a shipboard environment is increasingly complex. As highlighted in module 1, sleep quantity and quality (and its restorative value) depends on going through uninterrupted sleep. The more sleep is fragmented by waking up, the less restorative value sleep has in terms of how seafarers feel and function when they are on duty.

  24. Shipboard-related factors that affect sleep include the design of duty schedules, i.e. length and timing of duty periods, length and timing of breaks within and between a duty period, and the environment, e.g. heat, humidity, noise, vibration, lighting levels, ship routines, diet. These can all have negative effects on the amount of time seafarers are allocated for sleep in a 24-hour period.

    Duty scheduling and planning

  25. Duty scheduling and planning is a key factor in managing fatigue. Hence, the company should be responsible for ensuring duty schedules provide adequate opportunity for sleep.

  26. Companies must, at the very least, be in compliance with STCW regulation VIII/1.

  27. From a practical perspective, it is important to determine whether a given duty schedule, on average, enables adequate sleep opportunity. There are seven primary duty schedule considerations that should be taken into account when scheduling. They are:

    .1 Work hours (work periods): as indicated in module 1, as the length of a given period of work increases, the subsequent sleep opportunity decreases. Research has demonstrated that, apart from a reduction in performance, extended hours of work are also associated with reduced individual well-being, reduced organizational commitment and poor health outcomes. Administrative work, shipboard drills, training, ship loading and unloading tasks are all tasks that may affect seafarers' opportunities to gain adequate sleep. These factors in turn have been linked to declining levels of productivity and safety.

    .2 Rest hours (rest periods) between work periods: this is the length of time off between work periods and should reflect the fact that seafarers do not simply fall asleep as soon as they are off duty and wake just before they go back on duty. Seafarers, like shore-based workers, have many activities and responsibilities to manage between work periods such as eating, showering, socializing with other crew, relaxing, studying and writing to and communicating with family members and friends back home. Fatigue increases as the number of rest hours decrease; therefore rest hours should provide for adequate sleep opportunity, time to complete those other tasks noted above, be adaptable to the individual circadian rhythm and account for the effects of sleep inertia after waking. Hence, the interval between two successive work periods should allow sufficient time to obtain adequate sleep before the start of the next work period.

    .3 Night watches or work: as indicated in module 1, seafarers working during night-time, specifically during the circadian low, can experience severe performance degradation initially. If the seafarer maintains a regular schedule they may adapt over time. However, it is important to provide those seafarers working during night-time with a good sleeping opportunity and environment during the day.

    .4 Short rest breaks within work periods: short rest breaks benefit performance and help maintain alertness. As indicated in module 1, one of the most important determinants of fatigue is "time on task". Frequent short breaks are associated with performance benefits and result in better fatigue management when the timing of rest is at the discretion of the individual. While it is recognized that this may not always be feasible in a shipboard environment, it should be noted that the "time on task" effect can also be reduced during the work period by task rotations/substitutions.

    .5 Naps: naps are an effective countermeasure to fatigue, exhaustion from long work hours and restricted sleep. Whether before an anticipated short night's sleep or after, brief naps improve performance and alertness, and delay fatigue-induced performance degradation. Overall, research has shown that the benefits of controlled napping outweigh the potential risks associated with sleep inertia.

    .6 Recovery sleep: the provision for sufficient recovery time following periods of sleep debt is important. It should be noted that provision of minimum rest periods may not sufficiently acknowledge the critical role that the circadian rhythm plays in the rate at which fatigue accumulates and the rate at which people recover. To work safely across a given duty and to then return to the next work period sufficiently recovered requires that the seafarer obtains sufficient quantity and quality of sleep between work periods. Sleep opportunities during the circadian low are preferable because sleep that occurs during the circadian low provides the most recuperative value.

    .7 Reset breaks: as the risk of fatigue increases over successive work days of sleep debt, it seems logical that some "recovery" must take place over spans of rest days. This is typically an issue at sea as seafarers are exposed to potentially arduous duty schedules over a long period of time (in excess of seven days, sometimes months on end) without the possibility of a reset break. It is recognized that in a shipboard environment this is likely not practical; however, this may be a factor to consider when determining crew rotation.

  28. Companies should consider napping and short break policies to manage fatigue if practicable.

  29. Companies should also acknowledge impairment through sleep inertia when planning tasks and activities, giving adequate time for seafarers to be alert before performing critical tasks, when possible.

    Tools to assess fatigue in scheduling

  30. The planning of duty schedules based on fatigue science as well as operational requirements permits predictive identification of fatigue hazards. This assists in allocating adequate rest periods that provide sufficient sleep opportunity.

  31. There are useful additional tools for the mitigation and control of fatigue such as:

    .1 fatigue risk assessment tools: the risk level of a specific duty schedule may be assessed via a fatigue risk score; and

    .2 fatigue predictive software tools: models and related software to predict fatigue levels for specific operations can be useful additional tools for the management of fatigue risks, as mentioned in paragraph 7.

  32. Such tools should not be used in isolation nor be the main driver for duty scheduling decisions, as they are not sufficient to determine the full extent of fatigue-related risk. They should always be supported by other operational data. Their main purpose should be limited to identifying potentially fatigue-inducing duty schedules or scheduling hot spots and allow for better decisions in the selection of duty schedules. This is because numerous unforeseen circumstances can cause changes to planned schedules, e.g. weather conditions, unexpected technical problems or seafarers' illnesses. Seafarer fatigue is the result of what is actually worked, not what is planned. Thus another proactive approach for identifying fatigue hazards is to analyse actual duty schedules in operation.

    Workload management

  33. As discussed in module 1, mental and physical demands of work can contribute to a seafarer becoming impaired by fatigue in a number of ways. Concentrating for extended periods of time, performing repetitious or monotonous work, and performing work that requires continued physical effort can increase the risk of fatigue. Mental fatigue and physical fatigue are different and a seafarer can experience them at the same time. It is important to be aware of a seafarer's optimal level of workload and stress, and to have realistic attitudes towards these. Understanding that different people react differently to stressful situations (such as emergencies, family problems at home, job-related) is critical for effective interventions. Hence, the use of effective communication with seafarers and monitoring and observing any behaviours that may indicate a change to a seafarer's fatigue as a result of workload is important (see fatigue signs and symptoms in module 1) .

  34. Typical techniques for managing workload while on duty include prioritization of tasks, task delegation, task rotation, crew rotation and task shedding. A list of risk mitigation strategies that should be used in managing workload may include:

    .1 Carefully considering task design according to the workload and the available resources, including manning.

    .2 Reducing the amount of time seafarers need to spend performing sustained physically and mentally demanding work (e.g. tank cleaning, navigation through congested waters).

    .3 Managing workload and work-pace change caused by machinery breakdowns and planned and unplanned sicknesses and illnesses.

    .4 Where practicable, minimizing routine and administrative tasks or redesigning them to ensure seafarers can focus on core duties in their working time.

    .5 Minimize repetitive or monotonous tasks by using task rotation, where practicable.

    .6 Where practicable, defer non-urgent work to allow appropriate rest and recovery if necessary.

    Work and living environment

  35. The work and living environment is important for ensuring adequate opportunity for sleep and should be considered. Because good quality sleep is critical, companies should develop procedures to minimize interruptions to seafarers' sleep. Opportunities for implementing countermeasures in this area vary from shipboard environmental, procedural to operational changes. For example, most environmental aspects such as noise can be better addressed during ship design (see module 5). However, there are control measures that the company can implement to assist in reducing noise levels in the sleeping environment.

  36. Environmental, procedural and operational measures may also range from low-cost solutions, such as porthole blinds and door baffles, to high-cost solutions, such as refitting the ship exhaust or air conditioning systems.

  37. Operational and procedural changes may include developing napping policies or defining blocks of time (sleep opportunities) during which seafarers are not contacted except in emergencies. These protected sleep opportunities need to be known to all relevant personnel. Depending on the situation, changes should be made to those areas that will have the most impact, and following evaluation, consideration to other changes can then be made.

  38. Environmental control measures may include, but are not limited to:

    .1 adequate facilities for rest, sleep and meal breaks and other essential requirements, such as bathroom facilities and personal storage;

    .2 making sleeping areas darker, quieter and more comfortable and increasing lighting in certain areas of the ship, such as:

         .1 providing a dark sleeping atmosphere using blackout blinds for portholes or berths in sleeping spaces;
         .2 installing insulation baffles over cabin door louvres;
         .3 improving air conditioning (ambient temperature) and air flow; and
         .4 supplying good quality and comfortable bedding such as mattresses and pillows;

    .3 making sleeping spaces, including their location, a priority in retrofitting and new ship construction; and

    .4 ensuring adequate personal storage space is available for seafarers' personal effects.

  39. Procedural and operational control measures may include, but are not limited to:

    .1 increasing access to healthier food choices by ensuring nutritious food is served on board;

    .2 providing information and advice on healthy eating and physical well-being;

    .3 making exercise equipment and facilities available to seafarers;

    .4 providing and maintaining a quiet atmosphere for sleep; develop a "do not disturb" policy for sleeping seafarers;

    .5 where practicable, calls for drills should be conducted in a manner that minimizes the disturbance of rest periods as they can be extremely disruptive;

    .6 putting in place short breaks within duty periods, including napping policies;

    .7 ensuring ship routines such as meal times are commensurate with seafarer working schedules; this includes providing personnel working at night with appropriate meal choices;

    .8 providing access to counselling services to assist in any issues arising from the disruption to individual, family or social patterns and shipboard-related aspects; implement a consistent stress management programme;

    .9 have a policy in place to support seafarers experiencing elevated levels of workload;

    .10 if possible, avoid assigning seasick and ill seafarers shipboard work;

    .11 if possible, provide all seafarers with shipboard phone, internet and email access; and

    .12 if possible, ensure that maintenance work does not disrupt personnel sleeping.

    Adequate sleep obtained

  40. Given that sleep loss is a primary contributor to fatigue, the company should determine whether adequate sleep is obtained.

  41. Situations may arise where a seafarer is provided with an adequate sleep opportunity, but they may not get adequate sleep. Hence, while an adequate sleep opportunity provides an indication of the quantity of sleep likely to be obtained, it is important to know whether adequate sleep has actually been obtained. Seafarers should be provided with the opportunity to report situations when they have been unable to obtain adequate sleep or feel at risk of making fatigue-related errors without repercussions.

  42. In general, seafarers are responsible for using adequate sleep opportunity appropriately, so they are alert and capable of performing assigned shipboard work safely. However, there are a number of reasons why seafarers may not obtain adequate sleep. The aspects mentioned below can all affect the amount and quality of sleep obtained:

    .1 a seafarer working during the night may have difficulty getting quality sleep;

    .2 a seafarer upon joining the ship may experience difficulty adjusting to the sleep schedule;

    .3 a seafarer travelling for an extended time to the ship should not be required to report to work until adequate rest is obtained;

    .4 undiagnosed and untreated sleep disorders as highlighted in module 1;

    .5 emotional stress;

    .6 the sleeping environment (comfort, noise, darkness, ship motion, privacy, room location) 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 such as caffeine and amphetamines; and

    .10 use of personal electronic devices before sleep, which may delay the onset of sleep and not allow adequate sleep to be obtained.

  43. 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.

    What rules and regulations are in place to prevent and deal with fatigue (international, national and company)?

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


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