Comparing the work and rest hours of United States Navy Sailors with existing maritime regulations

Transcription

1 Comparing the work and rest hours of United States Navy Sailors with existing maritime regulations Nita Lewis Shattuck, Ph.D. Panagiotis Matsangas, Ph.D.

2 The Military Climate: Doing More with Less 2

3 Life at sea!

4 Life at sea!

5 Life at sea!

6 Life at sea!

7 Life at sea!

8 Life at sea!

9 Life at sea!

10 Life at sea!

11 Navy Personnel Male 84% Officers 17% 60% 50% 40% Officers Enlisted 30% 20% 10% Enlisted 83% Female 16% 0% 25 or younger 26 to to to or older

12 A Population of Shiftworkers and Poor Sleepers The US military indoctrinates healthy US adults into a culture of sleep deprivation that persists throughout their careers. Like other shiftworkers, members of the military frequently exhibit circadian scarring and often engage in binge sleeping. Based upon scientific findings from research on both civilian and military populations, these sleep practices are associated with decreased performance and long term health consequences.

13 Sleep debt begins on Day One of Military Service A Comparison of Sleep between Brown University Students and Cadets at USMA, West Point 8:24 7:12 6:45 6:52 7:04 6:59 6:00 4:48 4:50 5:06 5:17 5:12 Brown 3:36 USMA 2:24 1:12 0:00 1st Sem 2nd Sem 3rd Sem 4th Sem Note: Brown University data were collected on the Class of 1992 (Fall 1988 Spring 1990 using self-report. USMA data were collected using actigraphy on the Class of 2007 Fall 2003 Spring 2005 (Miller, Shattuck, & Matsangas, 2010).

14 and continues throughout their careers Even non-deployed military sleep fewer hours than civilians 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% 42% 27% Average Hours of Sleep per Day 21% 9% 2% Mysliwiec et al. (2012) 725 Army, Navy, Air Force 8% 21% 31% 33% 9% Krueger & Friedman (2009) 10,441 civilians < > 9

15 SSB N 730 SSN/ SSB N DDG 106 DDG 65 CVN 68 DDG 109 FFG 46 LCS 1 LCS 2 DDG 93 CG 73 CG 70 HSV 2 SWIFT CVN 74 Nov June / / NPS Sleep Studies During deployment Underway Training - RX Dep Underway Training - RX Dep Underway Training Independent steaming Rough Water Trials - SS 5-6 Rough Water Trials - SS 4 Calm Water Trials /05 Rough Water Trials - SS 4 Rough Water Trials - SS<4 Predeployment Workups Predeployment Workups Sea trials RIMPAC RIMPAC Sea trials GOMEX 05-1 Various operations Op. Enduring Freedom Sleep - Naval Operations n=129 n=127 n=120 n=34 n=102 n=19 n=19 n=25 n=21 n=29 n=24 n=20 n=41 n=28 n=42 n=19 n=21 n=167 n=33 Note 1: Blue bars indicate actigraphic sleep, gold bars 0 are self-reported sleep Daily Sleep [hrs] Note 2: Number centered on each bar refers to study sample size Note 3: Horizontal lines indicate one standard deviation Last update: Mar 2017

16 Shiftwork in U.S. Navy Watch schedules Circadian (24 hour) Non-Circadian 2-section 3-section 4-section 3-section 4-section 6/6 4/8 3/9 5/10 5/15 12/12 8/16 6/18 6/12 Workday includes duties other than watchstanding. Other watchbills may be implemented by the command

17 Actigram of a typical work/rest pattern at sea

18 Problem Statement and Study Goals Problem Statement Study goals Crewmembers in the United States Navy (USN) Work long hours with limited opportunities to sleep Are habitual shiftworkers Shifts result in circadian misalignment equating to an 15 or 20-hour day Have no weekends or time for recovery Compare the work and rest patterns of USN crewmembers with existing maritime regulations Investigate the association between the watchstanding schedule and the level of compliance with existing maritime fatigue regulations 18

19 Method Retrospective analysis of pre-collected data (N=184) USS NIMITZ (CVN-68) Reactor Department (RX) June 2014: 69 crewmembers using the 5hr-on/10hr-off schedule November 2014: 115 RX crewmembers using the 3hr-on/9hr-off schedule Sleep was assessed with wrist-worn actigraphy and daily activity logs 19

20 Method Activity log information aggregated in Work and Rest by day (midnight to midnight) Work time Watch periods, ship duties, maintenance, training, and service diversion Rest Personal time, sleep, and meals 20

21 Maritime working standards Work 14 hours/24-hour period Maritime Labour Convention (MLC) Work 72 hours/7-day period For seafarers Rest 77 hours/7-day period Standards United States Code (USC) Work 36 hours/3-day period USN does not have a regulation dedicated to work/rest times (except aviation) US Navy regulations Navy Availability Factor (NAF) Navy Standard Work Week (NSWW) obs. Work 81 hours/7-day period Sleep 56 hours/7-day period

22 Results Participants Predominantly young (25.0±3.72 years of age) Male (80%) Enlisted (95%) Crewmembers worked 14 hours/day for 21% of their workdays On a weekly basis, crewmembers Worked 72 hours for 75% of their 7-day periods Worked 81 hours for 53% of their 7-day periods Rested <77 hours for 23% of their 7-day periods Slept<56 hours (~8-hours/day) for 64% of the 7-day periods From actigraphy: Crewmembers working on the 5/10 schedule slept on average 6.88±0.93 hours/day, compared to 6.68±0.95 hours of sleep for their 3/9 peers. 22

23 USS Nimitz Results for Work Hours Non-compliance rates by work hours criterion Vertical lines denote the Standard Error of the Mean 24

24 USS Nimitz Results for Sleep/Rest Non-compliance rates by rest/sleep hours criterion Non-compliance rate refers to % of crewmembers Vertical lines denote the Standard Error of the Mean 25

25 Conclusions This study compared the compliance of crewmembers work/rest hours with existing regulations. Overall, non-compliance rates were high, up to 88% of the crew! Results highlight how crewmembers work long hours with limited opportunities to rest. The watchstanding schedules of the crewmembers had a significant impact on the compliance rates. In the absence of specific Navy regulations to manage work and rest schedules, the US Navy should consider using standard maritime regulations that include guidance for optimal management of work/rest/sleep patterns. 26

26 Questions? Contact information: Nita Lewis Shattuck, Ph.D. (831) NPS Crew Endurance Resource Website

27 Factors Leading to Disrupted Sleep at Sea Factors Leading to Disrupted Sleep at Sea Psychological- Pharmacological Environmental Berthing Compartment Habitability Organizational Stress, anxious thoughts Ship motion Lack of privacy Irregular sleep schedules Harassment from leadership, crewmembers Caffeine, energy drinks Nicotine External noise Smells Temperature extremes Internal noise Temperature Light in the compartment Watch schedules Long work hours Duties/operati onal commitments 28