1. Fatigue at Sea. Chronic health effects and preliminary results
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 April 2015

2. Interviews and questionnaires
Two companies in Europe
5 + 9 interviews
questionnaires
Two companies in China
interviews
questionnaires
In total 61 interviews and 937 questionnaires

3. Chronic health effects of fatigue Pathways
Autonomic nervous system
Immunologic
Metabolic

4. Chronic health effects of fatigue
Impaired cognition
Reduced alertness

5. 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

6. 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

7. 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

8. 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

9. One example: General fatigue Environmental 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? *
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*

10. Ranking of important predictors for fatigue for each category of fatigue
Variable
General fatigue
Fatigue at work
Fatigue after work
Environmental factors 1 3
Job demands 2 4
Getting up difficulties
Extent of fatigue when on watch -
How much sleep do you feel you get in general? 5
Do you regularly have the opportunity to gain at least 6 hours uninterupted rest? 6
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
Sleep quality

11. 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?

12. How to reduce fatigue – The analysis of questionnaire data
How useful the following measures in reducing fatigue divided by regions of companies (n=841)

13. How to reduce fatigue – Views from seafarers
Self-management
Self-discipline, taking all the time available to have a rest
Improve professional skills
Improve Senior officers’ management skills
Communicate with work mates and actively help each other
Companies’ management
Manage working-period at sea reasonably (6 months favoured by many Chinese seafarers)
Reduce workload by using electronic files and cutting out unnecessary jobs/papers
More attention to ship repair/maintenance in order to reduce work at sea
Sufficient time to relax on land in the daytime when ships call at port
More facilities for recreation and entertainment on board (inflatable swimming pool, treadmill, weights).
Communication equipment to facilitate contact with families to release pressure

14. 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.

15. Thank you for your attention!