Findings from Washington State University Update Knowledge of Risk Management (Sleep and performance in simulated Navy watch schedules)

Insurance Weekly News

By a News Reporter-Staff News Editor at Insurance Weekly News -- Investigators discuss new findings in Risk Management. According to news originating from Spokane, Washington, by VerticalNews correspondents, research stated, "To operate Navy ships 24 h per day, watchstanding is needed around the clock, with watch periods reflecting a variety of rotating or fixed shift schedules. The 5/15 watch schedule cycles through watch periods with 5 h on, 15 h off watch, such that watches occur 4 h earlier on the clock each day - that is, the watches rotate backward."

Our news journalists obtained a quote from the research from Washington State University, "The timing of sleep varies over 4-day cycles, and sleep is split on some days to accommodate nighttime watchstanding. The 3/9 watch schedule cycles through watch periods with 3 h on, 9 h off watch, allowing for consistent sleep timing over days. In some sections of the 3/9 watch schedule, sleep may need to be split to accommodate nighttime watchstanding. In both the 5/15 and 3/9 watch schedules, four watch sections alternate to cover the 24 h of the day. Here we compared sleep duration, psychomotor vigilance and subjective sleepiness in simulated sections of the 5/15 and 3/9 watch schedules. Fifteen healthy male subjects spent 6 consecutive days (5 nights) in the laboratory. Sleep opportunities were restricted to an average of 6.5 h daily. Actigraphically estimated sleep duration was 5.6 h per watch day on average, with no significant difference between watch sections. Sleep duration was not reduced when sleep opportunities were split. Psychomotor vigilance degraded over watch days, and tended to be more variable in the 5/15 than in the 3/9 watch sections. These laboratory-based findings suggest that Navy watch schedules are associated with cumulative sleep loss and a build-up of fatigue across days. The fixed watch periods of the 3/9 watch schedule appear to yield more stable performance than the backward rotating watch periods of the 5/15 watch schedule."

According to the news editors, the research concluded: "Optimal, performance may require longer and more consistent daily opportunities for sleep than are typically obtained in Navy operations."

For more information on this research see: Sleep and performance in simulated Navy watch schedules. Accident Analysis and Prevention, 2017;99():422-427. Accident Analysis and Prevention can be contacted at: Pergamon-Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, England. (Elsevier - www.elsevier.com; Accident Analysis and Prevention - www.journals.elsevier.com/accident-analysis-and-prevention/)

The news correspondents report that additional information may be obtained from E. Skornyakov, Washington State University, Elson S Floyd Coll Med, Spokane, WA 99210, United States. Additional authors for this research include N.L. Shattuck, M.A. Winser, P. Matsangas, A.R. Sparrow, M.E. Layton, R.J. Gabehart and H.P.A. Van Dongen.