A comparison between the 3/9 and the 5/10 watchbills
Download
Author
Shattuck, Nita Lewis
Matsangas, Panagiotis
Brown, Stephanie
Date
2015-04Metadata
Show full item recordAbstract
This is the second phase of a longitudinal study comparing the fatigue levels, workload, and performance of crewmembers working
on the 3-hrs on/9-hrs off (3/9) and the 5-hrs on/10-hrs off (5/10) watchstanding schedules. Detailed results on the 5/10 are included
elsewhere (Shattuck, Matsangas, & Powley, 2015). Crewmembers from the Reactor Department on the USS NIMITZ (N=117,
24.6±3.89 years old, 95 males, 109 enlisted, with 4.25±2.65 years of active duty) participated in this study. Results show that the 3/9
is better than the 5/10 in terms of sleep quality, subjective levels of fatigue, mood, psychomotor vigilance performance, and
acceptance by the Sailors. Although crewmembers on both the 5/10 and the 3/9 received, on average, approximately seven hours of
sleep per day, the sleep hygiene and acceptance of the two schedules differ considerably. On the 3/9, significantly fewer Sailors
reported not having enough time to sleep, as contrasted with the 5/10 (3/9: 52%; 5/10: 88%; p<0.001). There were differences
between crewmembers on the two schedules in the expression of negative opinions about the adequacy of their sleep (3/9: 30%; 5/10:
80%) with over twice as many negative opinions for the 5/10 group. Daytime sleepiness and mood states deteriorated during the
underway when using the 5/10, whereas daytime sleepiness and mood states of Sailors on the 3/9 did not change. Crewmembers on
the 5/10 also had lower psychomotor vigilance performance than their counterparts on the 3/9 schedule (15% longer reaction times
and 59% more 355-millisecond lapses greater combined with false starts). Crewmembers on the 5/10 also had lower psychomotor
vigilance performance than their counterparts on the 3/9 schedule (15% longer reaction times and 59% more 355-millisecond lapses
greater combined with false starts). Overall, these results may be explained by considering the timing of sleep and the periods of
sustained wakefulness experienced on the 5/10. Over a 3-day rotation cycle, a crewmember on the 5/10 watchstanding schedule sleeps
at three distinctly different times on each subsequent day, experiences two periods of sustained wakefulness, and has one night with
only a 4-hour opportunity for sleep. In contrast, Sailors on the 3/9 have a fixed sleep schedule every day and they experience, at most,
16- to 17-hour periods of sustained wakefulness. Even though the 3/9 schedule, as a whole, is better than the 5/10, analysis showed
that two 3/9 watch sections, those standing the night watches, were accepted less by the Sailors. We postulate that concerns about the
implementation of the 3/9 schedule may be ameliorated by adjusting sunlight exposure, providing sleep hygiene training, and by
considering an alternative distribution of duties between watch sections to allow protected sleep times for those on night watch duty.
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.NPS Report Number
NPS-OR-15-006Related items
Showing items related by title, author, creator and subject.
-
Sleep patterns, mood, psychomotor vigilance performance, and command resilience of watchstanders on the “five and dime” watchbill
Shattuck, Nita Lewis; Matsangas, Panagiotis; Powley, Edward H. (Monterey, California. Naval Postgraduate School, 2015-02); NPS-OR-15-003This study assesses crew rest and sleep patterns, psychomotor vigilance performance, work demands and rest opportunities, organization commitment, and psychological safety and command resilience of Sailors in the Reactor ... -
Operational assessment of the 5-h on/10-h off watchstanding schedule on a US Navy ship: sleep patterns, mood and psychomotor vigilance performance of crewmembers in the nuclear reactor department
Shattuck, Nita Lewis; Matsangas, Panagiotis (Taylor & Francis, 2016);We assessed sleep patterns, psychomotor vigilance performance, work demands and mood of 77 crewmembers of USS NIMITZ (CVN-68) on the rotating 5-h on/10-h off (5/10) watchstanding schedule. Within the 3-day ... -
Comparison of the 3/9 and 6/6 Watchstanding Schedules for Crewmembers of a U.S. Navy destroyer
Shattuck, Nita Lewis; Matsangas, Panagiotis (SAGE, 2016);This naturalistic study of 52 sailors on the USS Jason Dunham (DDG-109) compared actigraphic sleep and psychomotor vigilance performance of crewmembers working a 3hours-on/9hours-off (“3/9”) with the performance of their ...