Citation

Lutzhoft M, Thorslund B, Kircher A, Gillberg M. VTI Rap. 2007; 2007(586A): 1-102.

Copyright

(Copyright © 2007, Statens vag- och trafikinstitut (VTI))

DOI

unavailable

PMID

unavailable

Abstract

The purpose of this study was to collect data about the fatigue level of bridge watch keepers to use for revising earlier sleep models, and devise innovative solutions for the shipping industry. Data collection included interviews with shipping companies and a field study onboard 13 cargo vessels. Thirty two participants took part in representing two watch systems; 2-watch and 3-watch. Subjective sleepiness and stress estimations were performed once every hour. Electrooculography (EOG) was used to record eye movement behaviour. Reaction time test was used to examine performance. 3-watch participants are more satisfied with their working hours and working situation. Tendencies indicate that 2-watch participants are a bit more tired, though the stress is the same. All are less sleep and less stressed at home. Time on the shift had an effect on sleepiness. The highest Karolinska Sleepiness Scale (KSS) scores were recorded in the late night and early morning. After a night shift the reaction times have higher variance, and a greater number of long reaction times are present. The mean value after a night shift was significantly higher than after a day shift. All thirteen shipping companies agreed that officers on the bridge always have tasks sensitive to fatigue, but no company experienced fatigue as a problem during normal conditions. All were positive to monitory devices, mentioning safety matters.