Zhiwei Zhao & Jørgen Riis Jepsen:

Fatigue at Sea. Chronic health effects and preliminary results

from an interview and questionnaire study of European and Chinese seafarers

The 18th Annual European Manning and Training Conference Copenhagen 28-29 April 2015zhao@sdu.dk, jriis@cmss.sdu.dk

Interviews and questionnaires

Two companies in Europe 5 + 9 interviews 314 + 140 questionnaires

Two companies in China 20 + 17 interviews 230 + 253 questionnaires

In total 61 interviews and 937 questionnaires

Chronic health effects of fatigue

Pathways

Autonomic nervous system Immunologic Metabolic

Chronic health effects of fatigue

Impaired cognition Reduced alertness

Chronic health effects of fatigue due to lack of sleep

Metabolic disorders• Obesity• Metabolic syndrome• Diabetes II• Hyper-lipaemia

Cardiovascular disorders• Hypertension• Atherosclerosis• Stroke• Myocardial infarction

Chronic health effects of fatigue Sleeping disorders

Insomnia Sleep apnoea/hypopnoea Delayed/advanced sleep phase syndrome

Gastrointestinal disorders Peptic ulcer Irritable bowel syndrome

Common infections Mental disorders

Depression Cancer Multiple sclerosis

Competing factors on board that contribute to the adverse health effects of fatigue

Nutrition Quality Quantity Soft drinks Sweets

Energy expenditure Sedentary work Exercise

Smoking

Predictive fatigue risk factors Regression analysis based on questionnaire data

The analyses focus specifically on the prediction of fatigue outcomes according to three fatigue scales:

General fatigue

Fatigue at work

Fatigue after work

A means of clarifying the relative importance and the intercorrelation of various predictive factors already identified as useful in predicting fatigue

Provides a more precise interpretation of the findings, incorporating the fact that certain fatigue risk factors are more predictive of fatigue than others

Facilitates the development of a more comprehensive picture of seafarers’ fatigue

One example: General fatigueEnvironmental factors were the most important

in predicting general fatigue.However, the actual construct and correlated attributes

of environmental factors appear to be complex

Variable selected Variables identified as highly related to environmental factors

Pearson correlation

Environmental factors-Bad weather-Temperature-Quality of bed-Light-Noise-Ship motion-Other environmental factor

How much sleep do you feel you get in general?

- 0.397*

Do you ever consider your working hours to present a danger to your personal health and safety?

0.303*

Do you find the switch from working at sea to working in the port particularly fatiguing?

0.268*

Ranking of important predictors forfatigue for each category of fatigueVariable General

fatigueFatigue at work

Fatigue after work

Environmental factors 1 3 1

Job demands 2 2 4

Getting up difficulties 3 1 3

Extent of fatigue when on watch 4 - 2

How much sleep do you feel you get in general? 5 5 5

Do you regularly have the opportunity to gain at least 6 hours uninterupted rest?

6 4 -

After arriving to the ship, did you have the opportunity to sleep before starting your first shift at work?

7 - -

Number of crew members on present ship - 6 7

Sleep quality - - 6

Additional predictors Subsequent to the regression analyses four more variables were identified as especially useful in terms of predicting fatigue, including

Age (Elderly more vulnerable) Rank (Officers more in risk) Do you regularly have the opportunity to

gain 10 hours rest in every 24-hr period? Do you ever consider your working hours

to present a danger to your personal health and safety?

How to reduce fatigue – The analysis of questionnaire data

How useful the following measures in reducing fatigue divided by regions of companies (n=841)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

Europe

China

How to reduce fatigue – Views from seafarers

Self-managementSelf-discipline, taking all the time available to have a restImprove professional skillsImprove Senior officers’ management skills Communicate with work mates and actively help each other

Companies’ managementManage working-period at sea reasonably (6 months favoured by many Chinese seafarers)Reduce workload by using electronic files and cutting out unnecessary jobs/papersMore attention to ship repair/maintenance in order to reduce work at seaSufficient time to relax on land in the daytime when ships call at portMore facilities for recreation and entertainment on board (inflatable swimming pool, treadmill, weights). Communication equipment to facilitate contact with families to release pressure

Current management of fatigue risks

Before going on board ships Companies provide training including methods for relieving pressure,

exercises and adjusted diet, etc. Seafarers assessed such training as unsystematic and with limited

effect.

On board ships Organizing collective activities, communicating with the crew and

expressing concern for them Promotion events held on a regular basis Paying close attention to the performance of crew to predict the degree

of their fatigue. Adjusting the rest time of seafarers in exceptional cases.

Thank you for your attention!