Systematic Review: Measurement Methods and Concept of Resilience Among Seafarers.

Shipping is considered a demanding environment that can significantly impact seafarers' well-being and mental health. This review aims to examine existing literature on the resilience of seafarers, with a focus on the measurement methods used. Furthermore, this study intends to gain a comprehensive understanding of the current state of research in the field of seafarers' resilience, examining the variations in defining and conceptualizing resilience across different studies and contexts. The review identified 99 studies published between 2003 and 2023, with ten studies being included in the final analysis. These studies employed various measurement methods and provided definitions of resilience. Five questionnaires were identified, with the Dispositional Resilience Scale-15 (DRS-15) being the most commonly used. Two of the selected studies had a longitudinal follow-up, while eight were cross-sectional. Four studies related to tankers, and an additional four studies focused on naval vessels, while two studies did not specify the vessel type. The publications were distributed in the period between 2003 and 2013 (two papers) and between 2013 and 2023 (eight papers). The identified themes encompassed shipboard stressors (three papers), sleep problems (two papers), occupational groups or attitudes (two papers), experiences in war (two papers), and intervention measures (one paper), highlighting the multidimensional nature of resilience within the maritime field. This review suggests a research gap, as it reveals that the topic of resilience in seafaring has been sparsely represented. Despite an increasing interest in recent years, research remains limited, particularly in the civilian maritime sector. Therefore, this review highlights the importance of understanding and promoting resilience among seafarers. While the variety of questionnaires used was limited, achieving consensus and standardization in resilience measurement is essential for more comparable and consistent research findings. Recognizing resilience as a crucial resource can promote the development of targeted interventions and support systems, enhancing seafarers' well-being and mental health.

Are there differences between officers and ratings on merchant vessels concerning effort-reward imbalance: a cross-sectional maritime field study.

PURPOSE: Today, measures to economise in the operation of ships can cause either an effort-reward imbalance or health impairments. The goal of this study was to assess the risk of effort-reward imbalance including overcommitment among officers and ratings on merchant vessels during their assignments and to evaluate lifestyle factors of seafarers as well as the health-promoting conditions on board. METHODS: A study sample of 308 male seafarers was examined during a total of 20 sea voyages on German container ships (participation rate 91.9%). RESULTS: Only 11 seafarers were identified as having an increased health risk of an effort-reward imbalance (ER ratio > 1). Officers tended to have a higher risk of an elevated ratio than ratings (4.4% vs. 3.1%) and also showed a significantly higher risk of an ER ratio above the median (58.8% vs. 41.8%; p = 0.022). Compared to land-based populations, the average overcommitment score of seafarers was high (17.9)-particularly among officers (20.3 vs. 16.5; p = 0.031). This corresponded to an elevated risk of overcommitment among officers compared to ratings (OR 2.14; 95% CI 1.78-2.37). This elevated risk remained significant after adjustment for age (OR 2.11; 95% CI 1.76-2.35) and job-related stressors. CONCLUSION: Although an elevated risk of effort-reward imbalance was only observed in few seafarers, this study revealed a high prevalence of overcommitment particularly among officers. In the course of time, overcommitment can lead to mental exhaustion. Therefore, shipboard health-promoting conditions need to be optimised.

Online survey among maritime pilots: job-related stress and strain and the effects on their work ability.

BACKGROUND: Maritime pilots often navigate ships through challenging waterways. The required 24 h standby rotation system (ROS) poses a stressful working situation. This study aims to describe the current job-related stress and strain among maritime pilots and the effects on their work ability, taking into account the different rotation systems. METHODS: Within a cross-sectional survey, pilots of all German pilots' associations were asked to complete an online questionnaire. The 1-week ROS (port pilots) was compared with the 4-month ROS (sea and canal pilots). The pilots' subjective perception of stress and strain was assessed using an established ship-specific questionnaire. Daily sleepiness and work ability were examined respectively using the Epworth Sleepiness Scale (ESS) and the Work Ability Index (WAI). RESULTS: The study group consisted of 401 male German pilots with an average age of 48.5 years (participation rate 46.9%). More than 50% of the pilots evaluated irregular working hours as the main stressor in their job. 79.8% of the pilots (especially 4-month ROS) experienced high psychological demands in their workplace. 83.3% stated having regularly neglected their private obligations due to job assignments. Pilots from the 4-month ROS experienced insufficiently predictable free time and long operation times at a stretch as stressors (p < 0.001 and p = 0.037). Elevated daily sleepiness was found in 41.9% of the pilots. The overall evaluation of the WAI questionnaire showed good to very good work ability at 77.3%. Additionally, no significant differences in the daily sleepiness or the work ability were observed between the pilots of the different two ROS. CONCLUSIONS: Due to their subjectively higher job-related mental demands, their disturbed work-life balance, and their long operation times at a stretch, it is likely that pilots from the 4-month ROS have significantly higher job stress compared to those in the 1-week ROS. However, this does not lead to more sleepiness or reduced work ability, which suggests that the pilots of this ROS are highly adapted to their working situation. Nevertheless, intervention measures with shortened ROS amongst sea and canal pilots' associations should be tested in respect of benefit, practicability and acceptance by the pilots.

Systematic Review on Outbreaks of SARS-CoV-2 on Cruise, Navy and Cargo Ships.

The confined environment of a ship promotes the transmission of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) due to close contact among the population on board. The study aims to provide an overview of outbreaks of SARS-CoV-2 on board of cruise, navy or cargo ships, to identify relevant outbreak management techniques, related problems and to derive recommendations for prevention. Four databases were searched. The study selection included reports about seroprevalences or clinically/laboratory confirmed infections of SARS-CoV-2 on board ships between the first of January, 2020 and the end of July, 2020. A total of 37 studies were included of whom 33 reported outbreaks of SARS-CoV-2 on cruise ships (27 studies referred to the Diamond Princess). Two studies considered outbreaks on the Grand Princess, three studies informed about Nile River cruises and one study about the MS Westerdam (mention of multiple outbreaks possible in one study). Additionally, three studies reported outbreaks of SARS-CoV-2 on navy vessels and one study referred to a cargo ship. Problems in handling outbreaks resulted from a high number of asymptomatic infections, transportation issues, challenges in communication or limited access to health care. Responsible operators need to implement infection control measures which should be described in outbreak management plans for ships to prevent transmission risks, including, e.g., education, testing strategies, communication lines, social distancing and hygiene regulations.

Objective and subjective measures to assess stress among seafarers.

BACKGROUND: Working and living on board merchant vessels often constitute high psychophysical stress for the crews. In this study, the current stress of seafarers is examined by using observation-based and subjective measures. MATERIALS AND METHODS: The workplaces of 70 crew members on board 11 container ships were analysed and evaluated using the objective instrument for the situational screening of mental workload (SMW-S). In addition, standardised interviews were carried out with 198 seafarers about their subjectively experienced stress. RESULTS: According to SMW-S, nautical and technical officers experience psychological strain due to their limited decision latitude, risky work situations and the physical and psychosocial working conditions. Among the ratings, psychological distress is more likely due to the limited decision latitude, physical and psychosocial working conditions and low qualification requirements (and, for the engine room ratings, given the low complexity and variability in their work). The interview results show that the irregular work is stressful for 79% of seafarers, the long working periods for 77%, the long working hours per day for 69% and working under time pressure for 62%. Additional psychosocial burdens are present for 95% of seafarers due to family separation and for 65% due to existing social differences in a multicultural occupation. CONCLUSIONS: Considering the stressful work on board, particular attention must be paid to shipping-specific conditions such as long working times, family and socio-cultural separation and living together in a heterogeneous crew.

Training seafarers to deal with multicultural crew members and stress on board.

BACKGROUND: The present study describes the intercultural differences in the perception of stress and the preparation of seafarers. MATERIALS AND METHODS: Three hundred twenty-three seafarers (156 [48.3%] Europeans and 167 [51.7%] Southeast Asians) were interviewed about their subjective stress on board. RESULTS: According to the interviews with ship's officers, mostly represented by Europeans, mental stress was most often due to high responsibilities (82.0%), extensive administrative tasks (81.1%) and lack of qualification of seafarers (64.8%). Subjectively, the Europeans questioned were significantly more likely to experience mental stress on board than the Southeast Asians (74.2% vs. 56.3%), whereas the latter were more prone to being physically stressed. 43.1% of the Southeast Asian seafarers often felt lonely on board compared with 26.2% of the Europeans. Preparation for maritime-specific stress in the form of specific training units is only provided in 1 of the 5 universities surveyed. The most important reason for this is a lack of time. Intercultural leadership training was also only offered at one university. CONCLUSIONS: In view of the many psychophysical stressors in daily life on a ship and the lacking respective education, it is recommended to integrate stress management and diversity training in intercultural communication in the higher education of future superiors on board.

Physical influences on seafarers are different during their voyage episodes of port stay, river passage and sea passage: A maritime field study.

INTRODUCTION: During a sea voyage, crew members of vessels are permanently exposed to physical stress caused by noise, vibration and heat. This study aims to describe the extent of the physical influences on board container ships and the resulting stress. METHODS: Up to four scientific investigators accompanied six sea voyages on container ships under German management. Workplace and person-related measurements for noise, vibration and climatic parameters were carried out on the vessels during the three different voyage episodes (port stay, river passage and sea passage). RESULTS: The interviewed seafarers reported, in decreasing order, the level of psychological stress due to vibration (80.6%), noise (71.8%) and, much less, heat (45.7%) in the workplace. In terms of workplace-related physical measurements, the highest noise levels were found in the engine room (104 dB (A)), in the workshop (81 dB (A)) and on deck (77 dB (A)), irrespective of the voyage episode. Some noise measurements in the recreational area revealed levels above the threshold. All measured 180 vibration values were below the relevant threshold limits-with the highest values in the engine room (62 mm/s2), followed by the workshop (37 mm/s2) and the engine control room (34 mm/s2). In terms of thermal comfort, none of the measured climatic parameters differed significantly between the voyage episodes. According to the person-related physical measurements, the noise exposure was particularly pronounced among the engine room personnel with an average noise level of 96 dB (A) (often during cleaning, painting and repair work). In contrast, the deck crew and nautical officers were respectively exposed to an average level of 83 dB (A) and 77 dB (A) at work. DISCUSSION: A relevant stress level due to physical loads was detectable in the present study. As ship crews are exposed to the physical influences on board for 7 days a week over several months, further research is recommended to assess the long-term health effects for seafarers.

Reply to Comment on Oldenburg, M., Jensen, H.J. Stress and Strain among Seafarers Related to the Occupational Groups. Int. J. Environ. Res. Public Health 2019, doi:10.3390/ijerph16071153.

In respect of the above mentioned manuscript [...].

Work profile of maritime pilots in Germany.

Long and irregular shifts, unforeseeable operations and high responsibility are still prominent in the job of a pilot and pose high psycho-physical demands. Furthermore, there is a disturbed work-family balance. Working hours of pilots are highly variable and not bound by regulations due to irregularities of vessel traffic. The pilots have to work in a shifting rotation system. This paper demonstrates the stressors during their work routine and shows the usual working profile of a pilot during their service.

Needs and possibilities for ship's crews at high seas to communicate with their home.

OBJECTIVES: Good communication between seafarers and their families at home is essential to compensate for the work-related strain experienced on board ships. This paper presents the needs and possibilities for communication with home in seafaring. MATERIAL AND METHODS: In total, 323 seafarers were interviewed during their work assignments on board (the participation rate of 88.5%). The results were stratified by cultural background, family ties, rank groups and shipping routes. RESULTS: The average stay of the officers on board the current vessels lasted 4 months and that of the ratings 9 months (p < 0.001). About a third of the officers and a half of the ratings evaluated these lengths of stay as too long. In the study, only 50 participants (15.5%) mentioned that the Internet on board their previous vessel was available for private use. Only 40.6% of these crew members stated that they had used it on a daily basis. Particularly the seafarers assigned to worldwide destinations and crew members without children experienced the insufficient possibilities for telecommunication as work-related strain (OR 1.87, 95% CI: 1.15-3.04 respective OR 2.00, 95% CI: 1.03-3.88). The average amount of time spent on telecommunication amounted to more than 2.5 h/week (which equals approximately 20 min/day). The average cost of about USD 30/week for telecommunication was considered by 24.7% of the seafarers as "much too high." CONCLUSIONS: The fact that several crew members considered the time spans of their assignments as too long should lead to certain adjustments. In view of the importance of good options for shipboard telecommunication, this study makes an essential contribution to understanding the crews' needs. Measures should be taken to improve communication by allowing an easier access to information and communication technology (ICT) (on board and ashore), by offering cheaper fees, and by providing Internet access in their cabins. The study results show a substantial need to improve the means of communication on board ships. Int J Occup Med Environ Health. 2019;32(6):805-15.

Psychophysical stress and strain of maritime pilots in Germany. A cross-sectional study.

INTRODUCTION: Maritime pilots work in an irregular deployment system (rotation system) with unpredictable work assignments under high levels of physical and mental stress. Fatigue or chronic diseases, e.g. coronary heart disease, peptic ulcers or gastritis can occur as a consequence. This can lead to long-term limitations of pilots' work ability. The aim of this study is to analyse current stress and strain in maritime pilots. METHODS: Initially, all German pilots were interviewed with an online questionnaire about their living and working situation (response rate 43%). Subsequently, a medical and psychological examination of a random sample was carried out with pilots working in a 4-month rotation system compared with those working in a 1-week system. Most of the measurements took place at the beginning and the end of continuous work assignments each lasting several weeks (pre vs post-rotation). The questionnaires RESTQ-work 27, Resilience Scale RS-13 and Berlin Questionnaire were used as well as a sleeping diary. Furthermore, cardiovascular parameters (during rest and under ergometric stress), activity and blood parameters, urine stress hormones, and the pupillary unrest index were surveyed. RESULTS: 60 pilots were recorded with an average age of 48.7 years (SD 8.3 years). Among the parameters collected, there were no significant differences between pre and post-rotation examinations. Pilots with a 4-month rotation system experienced a much higher subjective strain level in RESTQ work-27 (OR 10.12 (95% CI 1.21-84.59)). According to the sleep diaries of the pilots working in a 4-month rotation system, reduced levels were found concerning the pre and post-rotation subjective performance level (p = 0.042 and 0.029), subjective sleep duration (p = 0.032) and current subjective feeling post-rotation (p = 0.036). Objectively measured arterial hypertension was significantly more frequent among pilots working 4 months at a time (OR 21.41 (95% CI 1.26-364.05)). In addition, elevated levels of total cholesterol, triglycerides and uric acid were more common among this group of pilots (p = 0.038, p = 0.033 and p = 0.038). In particular, the risk of hypertriglyceridemia was increased (OR 4.41 (95% CI 1.15-16.91)). DISCUSSION: Maritime pilotage represents a very straining profession that has been studied very little up to this point. The present results indicate that 4-month rotation systems lead to higher levels of subjective and objective strain than 1-week rotation systems. Interventions are therefore recommended; especially a change in the rotation system should be considered.

Sleepiness of day workers and watchkeepers on board at high seas: a cross-sectional study.

OBJECTIVES: To estimate the prevalence of sleepiness on duty among day workers and watchkeepers on board. DESIGN: Cross-sectional survey in a maritime field study. SETTING: 10 shipping companies with container vessels under German management. PARTICIPANTS: The whole crew (75 day workers and 123 watchkeepers) during 18 voyages on 18 different container ships. OUTCOME MEASURES: Sleepiness on duty and efficiency of sleep using pupillometry (in a cross-shift design) and the SenseWear armband activity monitor. RESULTS: The watchkeepers showed significantly shorter sleep periods than day workers (5.5 hours vs 5.8 hours). The average efficiency of sleep was 69.6% and significantly lower among watchkeepers (OR 0.48; 95% CI 0.26 to 0.88). 396 pupillometric examinations were carried out and revealed 88 study members (22.2%) with a pupillary unrest index (rPUI) in a range characterised as 'unfit for duty' and 110 seafarers (27.8%) categorised as 'particular attention required'. The average rPUI was similar between day workers and watchkeepers. The Epworth Sleepiness Scale revealed recent daytime sleepiness in 70 seafarers, which was similarly often stated by day workers and watchkeepers. Based on the Stanford Sleepiness Scale (SSS), a measurable cross-shift increase in the SSS value during the examined shift was observed, especially among watchkeepers. The amount of time already spent on the vessel at the time of the present examination was significantly associated with the rPUI (p=0.009). CONCLUSION: Sleep periods of both the day workers and the watchkeepers aboard vessels were alarmingly short and sleep efficiency was low. Sleepiness on duty is similarly prevalent among day workers and watchkeepers and seems to depend partly on the cumulative working period on the vessels. Preventive measures need to be taken by the shipping industry to counteract fatigue (eg, by enabling sufficient rest and sleep times).

Maritime field studies: methods for exploring seafarers' physical activity.

In order to determine the health status of seafarers, questionnaires are frequently applied or medical/ /psychological examinations conducted ashore, for example, in the form of medical fitness examinations or simulator training. In such a survey design, the occupational influences and the individual reaction cannot be ascertained. However, these aspects are especially important in the maritime context as employees on board are often exposed to the typical shipping-related stressors in the workplace for many months, both during working hours and during leisure time. In particular, it is assumed that working on board requires a high level of physical effort. Therefore, an exploration of occupational stress and strain, particularly the assessment of the seafarers' physical activity, should preferably be carried out in a comprehensive and realistic way in a maritime field study, i.e. an on-the-job survey directly on board.

Potentially traumatic experiences of seafarers.

BACKGROUND: The aim of the present study is to assess the extent to which seafarers had been affected by severe mental stress situations and what possible psychological effects they may have. METHODS: During the voyages of 22 German ships, a psychologically trained investigator interviewed 323 seafarers about severe mental stress or potentially traumatic events on board (participation rate 88.5%). Furthermore, a psychologist conducted semi-standardized interviews in 12 shipping companies and in 8 stations of the German Seafarers' Mission on seafarers' traumatic experiences. RESULTS: Of the seafarers surveyed on board, 116 (35.9%) experienced ship wrecks/severe accidents and 55 (17.0%) piracy on board. Experiences with stowaways were indicated by 126 seafarers (39.0%). Repeatedly having to unintentionally think about these events, being reminded of them by certain noises, smells, etc., or often dreaming of them were after-effects in 97 (83.6%) of the affected seafarers after ship wrecks/serious personal accidents on board and in 42 crew members (76.4%) after threats of piracy. Experiences of threat from stowaways had particularly affected non-European seafarers or ratings.According to the interviews with the shipping companies, a total of 14 deaths occurred in the last 3 years in the 12 interviewed shipping companies (due to heart attacks (3), severe cancer (3), very serious accidents (3), suicides (2) and 3 with unknown causes of death). In relation to the container ships of the investigated shipping companies, these frequencies correspond to a mortality rate of 78.4 per 100,000 seafarer years.According to the interviews in 8 Seafarers' Missions, these organizations are in charge of emergency counselling in the form of crisis intervention when a seafarer has experienced serious psychological stress. DISCUSSION: A serious injury or even the death of a member is a serious psychological stress experience for the other crew members in the closed social system on board. These events are particularly distressing for Filipino seafarers with their strong sociocentric bonds and religious values. Priestly support is often required in order to stabilize the Filipino crew members. CONCLUSION: As a preventive measure, psychoeducation for seafarers should be established for coping with extreme mental stress situations.

Stress and strain among merchant seafarers differs across the three voyage episodes of port stay, river passage and sea passage.

BACKGROUND: A sea voyage is characterized by a variety of work requirements for the ship's crew, basically reflected in three voyage episodes: port stay, river passage and sea passage. The primary aim of this study was to compare stress and strain amongst a sample of merchant seafarers across these three voyage episodes. METHODS: In a cross-sectional maritime field study, 323 sailors on 22 container ships were biometrically surveyed and completed a questionnaire. In addition, a survey of energy expenditure and heart rate (variability) was carried out in parallel with 236 participants with the SenseWear armband monitor and the RS 800 polar watch. RESULTS: Port stay and sea passage each accounted for the largest proportion of the ships' journeys, each at around 40%. The study participants rated port stay with 37.8% as the voyage episode with the highest strain, followed by the river passage (24.8%) and then the sea passage (13.0%). The working time during the sea passage was on average shorter than during port stay or the river passage (p<0.001)-as a result, seafarers had more spare time to spend on leisure and sleep. Total energy turnover and, by trend, work energy turnover were notably at the lowest during the sea passage. In particular, the crew had a significantly lower heart rate during the sea passage than during the other two voyage episodes (p = 0.001). Furthermore, there was no difference in the seafarers' heart rate variability between the voyage episodes. CONCLUSION: In the present study, it becomes clear that an accumulation of psychophysical stress takes place during port stay and leads to a subjectively and objectively higher strain level. In contrast, seafarers are more likely to recover during the sea passage. This knowledge should be used to offer ships' crews targeted health measures, in particular during the sea passage.

Maritime welfare facilities - utilization and relevance for the compensation of shipboard stress.

BACKGROUND: Maritime welfare institutions enable crew members of ships to use different recreation facilities ashore during their work assignments aboard. This study analyses the shipcrew members' need and their usage behavior of maritime welfare facilities that can be visited free of charge while their ship is in port. METHODS: A medically trained scientist interviewed 316 seafarers during 22 ship voyages. In addition, interviews were performed in 8 stations of the German Seamen's Missions. RESULTS: Port stay of the vessels accounted for 43.6% of the entire voyage duration. 279 seafarers (88.3%) stated having had opportunities for shore leave in order to visit maritime welfare facilities. Officers less often stated possibilities for shore leave than ratings (OR 0.40; 95%CI 0.24-0.67). The main reasons for shore leave were to contact family and friends and distraction from the everyday work on board. Short stays in port, a high workload and limited opportunities for reaching the welfare facilities were main obstacles to shore leave. Furthermore, several seafarers complained about poor information on board about the facilities. Among the various welfare institutions, a "very high importance" was attributed to Seamen's Missions and religious facilities (40% of the non-European seafarers - especially from Asia - and approx. 10% of the Europeans). CONCLUSION: This study reveals sufficient time periods for seafarers to leave the vessel in port, mainly depending on the number of terminals to be called at. During the vessels' port stay, a reduced workload for the shipping crew can be achieved by transferring several routine tasks to shoreside personnel. Furthermore, more attention should be paid to the accessibility of the welfare facilities and to better information about their offers. Measures should be taken to facilitate visits to maritime welfare facilities as an important refuge for seafarers.

Saliva cortisol level as a strain parameter for crews aboard merchant ships.

Seafarers working in maritime settings are affected by a great number of psychosocial stressors. The testing of cortisol in saliva is a well-established method for judging the individual strain. Therefore, this study aims to assess the crews' strain on container ships on the basis of this parameter, taking occupational groups and the three voyage episodes of the vessel into account (stay at port, river passage and sea passage). One scientist accompanied 22 sea voyages and examined 304 crew members who had provided a minimum of 5 saliva samples from at least one day. Altogether, 4,073 saliva samples were collected. An evaluation of stress hormones was conducted by analyzing on the basis of groups and day profiles. The present study revealed that the average concentration of cortisol in the saliva of the examined seafarers was lower during the first hour after waking up than that of a healthy reference population. There were significant differences in the cortisol between nautical officers, deck ratings, and engine room personnel with decreasing levels (p < .001). Furthermore, the highest cortisol level was measured during port stay followed by sea passages and river passages (p = .002). After adjustment, the average level of cortisol in saliva of the whole study group was positively associated with acute shipboard stressors, namely the average current working time (p = .050) and the average number of terminals that had been served during the last 7 days (p = .008). In contrast, no association of saliva cortisol was observed with age (p = .130), smoking status (p = .436), the current stay on board of the vessel (p = .230) or with the subjective stress evoked by noise, vibration, ship motion or psychophysical demands on board. Only the deck ratings and the engine room personnel displayed a continuous decrease in the cortisol level in the daily profile (p < .001). In total, the present study revealed an association of the saliva cortisol level among the examined crew with acute shipboard stressors, the working group, and the ship's voyage episode. A reliable collection of samples over several days on board is well possible through the presence of a specially trained person on site. In maritime studies, this high level of personal effort seems to be inevitable in order to allow a differentiated judgement of the hormone stress reaction of seafarers and meet high quality standards.

Recreational possibilities for seafarers during shipboard leisure time.

PURPOSE: This study is aiming to document the leisure time opportunities and their actual utilization on board merchant ships. METHODS: A scientist examined the whole crew on board 22 container ships (323 seafarers; participation rate 88.5%). Data about energy consumption and heart rate were continuously collected during the seafarers' leisure and sleeping time through a SenseWear® wrist monitor and a Polar watch RS 800 worn for at least 2.5 days. RESULTS: The seafarers spent an average of 28.2% of the day for leisure time activities and 32.6% for sleeping. A significantly higher energy consumption was found among deck ratings compared to engine room personnel and nautical officers. Across all occupational groups, the variability of the heart rate was lower during sleeping hours than during leisure time. Suggestions for substantial improvement of the leisure time opportunities on board included more frequent and free opportunities for telecommunication (59.1%), shorter work assignments, and a stronger cohesion of the crew. The following coping strategies were paramount: "calming down/settling down" (41.9%), getting in touch with the family (32.0%) and relaxing/sleeping (30.4%). CONCLUSIONS: The limited heart rate variability during sleeping hours suggests a reduced quality of sleep that might be due to the permanent heaving motions of the vessel, noise, and vibration. The (deck) ratings had more physical activities that corresponded with their higher energy consumption during leisure time. Altogether, there is a need to optimize opportunities for relaxation and recreation on board, taking into consideration characteristics of the different occupational and ethnic groups.

Cross-sectional study about the activities for various occupational groups on board during different voyage stages.

BACKGROUND: Employees on board must be highly qualified in order to be able to independently meet the different work requirements during the three voyage stages of a ship (port stay, river and sea passage). In this study, the activity profiles of the various occupational groups on container ships are presented according to the voyage stages. METHODS: As part of a maritime field study on 22 container ships in the North Sea area, the work processes of four different professional groups on board were evaluated, and a list of activity profiles was compiled. Directly after a voyage stage, the 323 seafarers participating in the study recorded the duration of each task within the recent voyage stage. The average proportion for each activity was determined and presented as a job activity profile. RESULTS: According to this profile, the diversity of tasks for the nautical officers and the deck ratings differ between the voyage stages. For watch officers, the focus of activity during port stay is on the preparation and monitoring of the loading process. During river and sea passages, more than 50% of the working time consists of monitoring the navigation area and about 10% of navigation. The main tasks for deck ratings during port stay include (preparation and follow-up) activities for loading and unloading the vessel and, during the other voyage stages, cleaning, painting and maintenance work on the ship. The activity profile for technical officers and engine room ratings less often differs significantly between the various voyage stages. There are numerous control, repair and maintenance tasks during the entire voyage. CONCLUSIONS: The established activity profiles show that the work diversity, especially among nautical officers and deck ratings, differs with a variety of requirements between the voyage stages. The activities of all four occupational groups varied most during port stay and less during the sea passage. To prepare maritime trainees for the expected job-related requirements and to identify the most suitable opportunities for recreation during a voyage, future maritime studies about stress on board should take the differences in the activities between occupational groups and the voyage stage into account.

Stress and Strain among Seafarers Related to the Occupational Groups.

The present study analyses whether the stress and strain experienced by seafarers differ between the various occupational groups on board container ships. In a maritime field study, 323 sailors on 22 container ships were asked to complete a questionnaire and were biometrically surveyed. In addition, a survey of energy expenditure and heart rate (variability) was carried out with the SenseWear® armband monitor and the Polar RS800 watch, respectively. The activity data objectively collected by the armband monitor showed an average sleep duration of 5.0 h per day, with particularly short sleep episodes amongst nautical officers. This occupational group also significantly more frequently reported sleep deficits (67%). The highest work-related energy expenditure per day was among the deck ratings (801 kcal), followed by the engine room personnel (777 kcal), and finally the nautical officers (568 kcal). The last-mentioned group, who were also the most likely to experience mental stress in the workplace, had the lowest heart rate variability compared to the other occupational groups. The average working time was the only stress parameter that correlated significantly negatively with the heart rate variability (r = -0.387; p = 0.002). Overall, job-related stressors of seafarers on board should be objectified in further studies and occupational group-specific health promotion programmes should be developed.