Sleepiness was higher during the night shift in the 6-on, 6-off system. Moreover, sleepiness increased more during the watch in the 6-on, 6-off system compared to the 4-on, 8-off system. There was a trend toward shorter sleep episodes in the 6-on, 6-off system and sleep was more often split into two episodes.

In this paper, we discuss the grounding of the Royal Majesty, reconstructed from the perspective of the crew. The aim is particularly to understand the role of automation in shaping crew assessments and actions. Automation is often introduced because of quantitative promises that : it will reduce human error ; reduce workload ; and increase efficiency. But as demonstrated by the Royal Majesty, as well as by numerous research results, automation has qualitative consequences for human work and safety, and does not simply replace human work with machine work. Automation changes the task it was meant to support ; it creates new error pathways, shifts consequences of error further into the future and delays opportunities for error detection and recovery. By going through the sequence of events that preceded the grounding of the Royal Majesty, we highlight the role that automation plays in the success and failure of navigation today. We then point to future directions on how to make automated systems into better team players.

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Seafarer sleepiness jeopardizes safety at sea and has been documented as a direct or contributing factor in many maritime accidents. This study investigates sleep, sleepiness, and neurobehavioral performance in a simulated 4 h on/8 h off watch system as well as the effects of a single free watch disturbance, simulating a condition of overtime work, resulting in 16 h of work in a row and a missed sleep opportunity. Thirty bridge officers (age 30 ± 6 yrs; 29 men) participated in bridge simulator trials on an identical 1-wk voyage in the North Sea and English Channel. The three watch teams started respectively with the 00-04, the 04-08, and the 08-12 watches. Participants rated their sleepiness every hour (Karolinska Sleepiness Scale [KSS]) and carried out a 5-min psychomotor vigilance test (PVT) test at the start and end of every watch. Polysomnography (PSG) was recorded during 6 watches in the first and the second half of the week. KSS was higher during the first (mean ± SD: 4.0 ± 0.2) compared with the second (3.3 ± 0.2) watch of the day (p < 0.001). In addition, it increased with hours on watch (p < 0.001), peaking at the end of watch (4.1 ± 0.2). The free watch disturbance increased KSS profoundly (p < 0.001): from 4.2 ± 0.2 to 6.5 ± 0.3. PVT reaction times were slower during the first (290 ± 6 ms) compared with the second (280 ± 6 ms) watch of the day (p < 0.001) as well as at the end of the watch (289 ± 6 ms) compared with the start (281 ± 6 ms; p = 0.001). The free watch disturbance increased reaction times (p < 0.001) from 283 ± 5 to 306 ± 7 ms. Similar effects were observed for PVT lapses. One third of all participants slept during at least one of the PSG watches. Sleep on watch was most abundant in the team working 00-04 and it increased following the free watch disturbance. This study reveals that-within a 4 h on/8 h off shift system-subjective and objective sleepiness peak during the night and early morning watches, coinciding with a time frame in which relatively many maritime accidents occur. In addition, we showed that overtime work strongly increases sleepiness. Finally, a striking amount of participants fell asleep while on duty.

Maritime shipping operates within a complex operational setting and incorporates many types of workplaces and work roles. The maritime domain has been a bit slower than other complex domains in its research and development of human factors and ergonomics application. The problem remains that the operator is continuously being excluded from the loop, which increases the probability of shipboard errors and accidents. This chapter begins by providing a general introduction to the maritime domain and its unique characteristics and is followed by a section on the information environment on the bridge. The section on the information environment on the bridge highlights the importance of integrating the end user into the bridge system and how technology must provide intuitive information at the right level of complexity at the right time. The main focus of this chapter is then split into two areas of current high significance: fatigue on board and maritime culture (also incorporating safety culture issues). Fatigue on board is of major concern, and most studies indicate that a systems approach must be adopted. This approach should account for aspects such as the number of personnel, trip length, frequency and duration of port visits, and shift planning. Within the area of maritime culture, multiculturalism and the way it is managed on board ships, including shipboard practices, affect safety. In the area of safety culture, three recommendations are central: (a) increase compliance with regulations, (b) implement a safety management system, and (c) implement a behavioral safety system. In general, this review indicates that more data are needed on human-technology-organizational issues in the maritime domain.