According to numerous studies, 60 to 80 percent of all maritime workplace incidents can be attributed to human error. Although there has been a continual downward trend in the overall number of incidents since 1987, human error remains a core issue within the Navy.1 The gradual decrease in incidents in large part can be attributed to the Navy’s procedural compliance campaign, which enhanced individual mishap case studies, created dedicated safety committees, and increased safety training.2 However, training and discussion can only do so much. The Navy can implement other changes to increase safety without sacrificing mission effectiveness. Ask any sailor who has been underway, and it will not be hard to find something all deployed ships are short of: Sleep.
According to the National Library of Medicine (NLM), negative incidents caused by sleep deprivation have been documented among truck drivers, aviation pilots, and among military personnel of all branches. In one study, the NLM concluded that sleep deprivation “impairs memory, decreases cognitive function, and results in poor decision-making.”3 The study showed that sleep-deprived nurses experienced a much higher percentage of errors than those who were considered non–sleep deprived. The study went on to propose an overall change in the 12-hour work shift standard prevalent in the medical community, recommending required minimum rest periods between shifts.
The study also acknowledged that sleep deprivation can be cumulative, so nurses who had been in the field longer posed even higher risks when sleep deprivation was involved. This observation is easily translated to naval work standards, meaning service members who do not get enough sleep are at higher risk of causing avoidable errors the longer they serve. Thus, alleviating sleep deprivation within the Navy should reduce mishaps.
The Necessary Amount of Sleep
Broken down, sleep comprises multiple REM cycles averaging 90 minutes each, with four stages per cycle. Studies suggest every adult needs four to six cycles or seven to eight hours of uninterrupted sleep per night.4 This means that every sailor should be allotted this time in their deployment schedule to maintain effectiveness and efficiency. However, this is easier said than done.
While underway, many sailors often must work 8- to 12-hour crew days in addition to standing various watches—many of them overnight. The shipboard workplace simply does not allow sailors to get the kind of sleep they need to perform at their peak—that is, unless scheduling changes are made.
The Navy is not blind to this problem. According to the 2021 Crew Endurance Handbook, sailors should get a minimum of 7.5 hours of sleep with at least 6 hours of that in an uninterrupted block supplemented with a two-hour nap.5 This guidance was issued two years ago, but many ships still have work to do to meet those recommendations.
Being underway has unique challenges and requirements, including the necessity of overnight work. However, with appropriate planning and schedule adherence, proper sleep patterns for all personnel are attainable. The 2021 Crew Endurance Handbook suggests the daily work schedule should be split into a rotating schedule for its personnel. There is no need for ships to limit themselves to two 12-hour work periods (or even three 8-hour work periods).
Shown in Figure 1 is one of the many watchbill recommendations offered by the handbook. It shows a busy work schedule that still allows time for sleep. Note that Section 1 has broken sleep periods as opposed to one full sleep period. This example, while a step in the right direction, is still inconsistent and not quite what is needed to alleviate sleep deprivation.
The Crew Endurance Handbook includes many different examples of ship schedules that lend themselves to healthy sleep, though all the templates have the same broken sleep issue for Section 1, which usually results in up to a third of the entire ship not getting the recommended sleep.
For the Navy to maximize individual rest and work safety, it would need to adopt individualized sleeping rotations by adapting the work schedule to include watch and duty requirements during the same 12- to 16-hour work period to separate—not mix with—rest or morale time.
For example, if a sailor has watchstanding duties that require them to be at their station from 0200 to 0600, instead of giving them the usual nighttime resting period that would then be interrupted, their workday could instead begin at 1600 at the earliest. This way, the sailor would perform their regular job duties from 1600 to 0200 (with meal breaks included), stand their watch, and then have a 10-hour period for personal time and uninterrupted sleep. Training on how to create dynamic watch/work/sleep schedules could help Navy leaders eliminate sleep deficits. This could be done at the officer or chief level, or even at the lead petty officer level, similar to how duty sections are already managed in the Navy.
The greatest reason to take proper sleep hygiene seriously is the link between sleep deprivation and the risk of suicide. A study produced by Stanford Medicine showed that participants who were given variable sleep schedules and interrupted sleeping hours were more likely to experience insomnia, nightmares, and suicidal ideation.6 This study supports regulated work schedules with little change and minimized interruption. Because sailors are in a high-stress environment underway, ensuring a healthy amount of rest would boost overall mental health. When it comes to the lives of sailors, a life-positive plan should not just be a priority the Navy claims to strive for—it should be the only option.
Regulating sleep is essential to increasing safety in the Navy. Mishaps increase in conjunction with sleep deprivation, which can be avoided with proper planning. In addition, scheduling proper rest periods for sailors could alleviate mental health issues and help decrease the suicide rate within the Navy.
Hopefully, there will soon be stricter adherence to the standards recommended in the Crew Endurance Handbook. A well-rested Navy is a battle-ready Navy.
Petty Officer Second Class Woolsey is a Navy rescue swimmer. He is currently assigned to Air Test and Evaluation Squadron Two One in Patuxent River, Massachusetts.
1. Javier Sanchez-Beaskoetxea et al., “Human Error in Marine Accidents: Is the Crew Normally to Blame?” Maritime Transport Research 2, 2021.
2. Megan Eckstein, “Navy, Marine Corps Had a Good Safety Record in 2020 But Have Plans to Get Better,” USNI News, 24 March 2021.
3. Mohamed Zaki Ramadan and Khalid Saad Al-Saleh, “The Association of Sleep Deprivation on the Occurrence of Errors by Nurses Who Work the Night Shift,” Current Health Science Journal 40, no. 2 (April–June 2014).
4. Goran Medic, Micheline Wille, and Michiel Hemels, “Short- and Long-Term Health Consequences of Sleep Disruption,” Journal of Nature and Science of Sleep 9 (19 May 2017).
5. Gidget Fuentes, “Latest Surface Navy Sleep Policy Aims for Better-Rested, More Alert, Healthier Crews,” USNI News, 28 January 2021; Nita Lewis Shattuck and Panagiotis Matsangas, NPS Crew Endurance Handbook 2.0 (Monterey, CA: Naval Postgraduate School, 2021), 22.
6. Erin Digitale, “Sleep Disturbances Predict Increased Risk for Suicidal Symptoms, Study Finds,” Med.Stanford.edu/news, 28 June 2017.