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From page 22...
... 22 3.1 Task 1. Outcome of the Kickoff Meetings 3.1.1 NCFRP Project 45 Panel Meeting At the initial kickoff meeting, the NCFRP Project 45 panel provided further clarification on their suggested changes to the research approach.
From page 23...
... Findings and Application 23 to participate, were given an online survey. The findings from these surveys and interviews are summarized in the following subsections.
From page 24...
... 24 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 3.2.1.1.1 Operational Practices Identified from Survey and Interviews. As part of the survey several operational factors were considered, including primary work schedule, number of vessels a company has, whether they use standby to load and unload, and, if they do, for how long, and do they change the schedule at these times.
From page 25...
... Findings and Application 25 from front watch to back watch after a few weeks. In this report, "front watch" is a term used to describe those crew working predominately during the day and with at least one rest interval during the nighttime hours.
From page 26...
... 26 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry sleeping environment a priority, there may still be room for improvement for some vessels as indicated in the crew survey (Section 3.4.3)
From page 27...
... Findings and Application 27 0% 20% 40% 60% 80% 100% < 30 30-99 100-299 300-899 ≥ 900 Reporting of medical conditions or medications that impact sleep (% companies) no-response NO YES Figure 7.
From page 28...
... 28 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry indicated that if the overall message is lost, training might be less effective than it would be if it is tailored to the specific type of operations. • Does your company offer screening, training, or education on sleep disorders?
From page 29...
... Findings and Application 29 • Does your company offer training or education on exercise or give access to exercise facilities? Exercise is an important factor in maintaining a healthy weight and has been shown to improve sleep quality, mood, and well-being (Reid et al.
From page 30...
... 30 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry have in place. A list of these meetings and interviews is provided in Table 6.
From page 31...
... Findings and Application 31 (see Appendix B for questions)
From page 32...
... 32 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 3.2.2 Summary of the Assessment of Best Practices from Other Industries Given that poor sleep efficiency and fatigue are common to many industries, the research team also sought to gather information from numerous sources outside of the tug/towboat/ barge industry about their fatigue management and/or sleep issues. This section provides a list of existing literature, interviews with experts and industry leaders (Table 8)
From page 33...
... Findings and Application 33 use of anchor sleep/nap sleep from over 200 crew members is provided in Table 10. This analysis indicated that the majority of crew (over 95%)
From page 34...
... 34 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 3.3.1 Phases II-III Data on the Use of an Anchor-Sleep/ Nap-Sleep Strategy Using both sleep diary and wrist actigraphy monitoring from the Phases II and III trials, it was determined that all but one of the 70 crew members studied met criteria for using an anchor-sleep/ nap-sleep strategy; that is they attempted to sleep in both of the rest opportunities each day on 90% of the monitored days. However, while almost all crew attempted to sleep in each rest opportunity, the wrist actigraphy data indicated that only 75% of the crew members actually managed to sleep in both sleep periods on 90% of days.
From page 35...
... Findings and Application 35 opportunity ranged from 1.5 to 5.7 hours. There were no significant differences in the sleep duration between the crew on the front watch and the back watch (Figure 13)
From page 36...
... 36 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 3.3.2 Phase IV Data on the Use of an Anchor-Sleep/ Nap-Sleep Strategy Phase IV used twice-daily sleep diaries to record various aspects of the sleep period, including time in bed and sleep duration. Data from the Phase IV trial indicated that 94.7% of the crew (127 out of 134 crew for whom sufficient data were available)
From page 37...
... Findings and Application 37 defined in the following way: morning preference were those who slept at least an hour more each day in the morning sleep period compared to the evening sleep period for >80% of recorded days; evening preference were those who slept at least an hour more in the evening sleep period compared to the morning sleep period for >80% of recorded days; neither were those who exhibited no preference either way. Average 24-hour sleep duration for the three preference groups is presented in Figure 16 for both the front watch and back watch crew.
From page 38...
... 38 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry Figure 17. Mean  SEM of change in KSS score from Phase IV based on preference for sleeping more in either the morning or evening sleep period.
From page 39...
... Findings and Application 39 3.3.3 Phase V Data on the Use of an Anchor-Sleep/Nap-Sleep Strategy Data from the new Phase V assessment indicate that 100% of the crew (14 crew members) used the split-sleep strategy.
From page 40...
... 40 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry work history. For a review and comparison of several of these mathematical models to predict fatigue see Mallis et al.
From page 41...
... Findings and Application 41 model has been used in the maritime sector successfully and referred the research team to key publications with the equations used to calculate the fatigue levels (Hursh et al.
From page 42...
... 42 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry A mathematical model (SAFTE/FAST) can be used to predict the effectiveness or performance of a single crew member.
From page 43...
... Findings and Application 43 Figure 22. SAFTE/FAST model output for an "average" crew member on a 6:6:6:6 schedule for the front watch with long sleep.
From page 44...
... 44 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 3.3.4.1.2 6:6:6:6 Front Watch: Short Sleeper [daily sleep duration of 360 minutes (6 hours)
From page 45...
... Figure 24. SAFTE/FAST model output for an "average" crew member on a 6:6:6:6 schedule for the back watch with long sleep.
From page 46...
... 46 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry Figure 26. SAFTE/FAST model output for an "average" crew member on a 6:6:6:6 schedule for the front watch with a skipped sleep period.
From page 47...
... Findings and Application 47 3.3.4.2 Other Reported Schedules Several other schedules were reported by management to be used as the primary watch schedule. This section models a few examples of these reported schedules.
From page 48...
... 48 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry Figure 29. SAFTE/FAST model output for an "average" crew member on a 12:12 schedule for the front watch with average sleep.
From page 49...
... Findings and Application 49 3.3.4.2.3 12:12 -- 21-day Rotation, 5 Days on/2 Days off, Front and Back Watch. The 12:12 schedule depicted in Figure 30 was reported to be in use by one of the surveyed companies.
From page 50...
... 50 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 8:4:4:8 schedule is typically a two-crew member operation. The 8:4:4:8 watch was not used as widely as in other maritime operations that have a three watch system.
From page 51...
... Findings and Application 51 Figure 33. SAFTE/FAST model output for an "average" crew member on an 8:4:4:8 schedule with 6 hours of good sleep.
From page 52...
... 52 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 3.3.4.2.6 4:4:4:4 Schedules. A single company reported using a 4:4:4:4 schedule.
From page 53...
... Findings and Application 53 Figure 36. SAFTE/FAST model scheduling grid for 7 days on a 4:4:4:4 schedule with 6 hours of good sleep, followed by 7 days on a 6:6:6:6 schedule with 7.5 hours (moderate sleepers)
From page 54...
... 54 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry interest for these "other" schedules. The second most commonly reported schedule within the tug/towboat/barge industry was the 12:12 schedule, which was used in a variety of ways and varied by start time, number of consecutive shifts worked, rotation of the schedule, and whether the crew slept on the vessel or at home.
From page 55...
... Findings and Application 55 3.4.1.1 Categorization of Long, Moderate, and Short Sleepers Data collected as part of the previously funded AWO Phase IV studies were reanalyzed to determine factors that may predict average daily sleep duration. Crew members were categorized into three groups (long, moderate, and short sleepers)
From page 56...
... 56 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry long sleepers, those on the back watch slept slightly less than those on the front watch. However, the opposite was the case when considering short sleepers.
From page 57...
... Findings and Application 57 3.4.1.1.3 Other Factors That Are Different Between Sleep Duration Groups. Differences in the characteristics of the three groups (short, moderate, long)
From page 58...
... 58 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry individual subjects (i.e., random effects)
From page 59...
... Findings and Application 59 • Factors predicting change in KSS score in the univariate analysis A regression analysis similar to what was done for predicting sleep duration was also conducted to examine factors that predicted a change in KSS score from the beginning to the end of the rest interval. There were some factors that were similar to those that were predictive for sleep duration in this model.
From page 60...
... 60 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry the rest period. For example, when the 24:00 to 06:00 rest period is considered as the reference, sleeping in the 06:00 to 12:00 rest period is predicted to result in 1.6 hours less sleep.
From page 61...
... Findings and Application 61 be expected, but factors related to difficulty sleeping (hard to fall asleep and sleep depth) , anxiety, and BMI were also associated with the change in KSS score.
From page 62...
... 62 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry 3.4.2.1 What Practices Did You Change? The research team specifically asked crew to provide examples of the type of practices that they had changed since participating in the Phase IV study.
From page 63...
... Findings and Application 63 3.4.3.1 Practices Crew Would Like Their Company to Initiate Crew were asked if there were practices they would like to see initiated, and 44% said yes. Practices that they would like to see initiated included diet regimes; good mattresses, beds and pillows; three-watch wheelhouse; 4:8 watch rotation; 7:5 watch rotation; more noise reduction around engine room; noise reduction through floors; individual thermostats in bunk rooms; stopping chipping and grinding (tie ship up to do that)
From page 64...
... 64 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry program was either not implemented or poorly implemented by many companies within the industry. This was particularly the case with the main audience of the program -- the crew -- since it suggested there be a change in work schedule to allow for 7 to 8 hours of uninterrupted sleep.
From page 65...
... Findings and Application 65 Section Practice Audience Current Practice/ Improvements Implementation Readiness Level 3.5.1 FRMS Management Policy makers Crew Unions 43% of survey companies not using CEMS/100% of companies to have FRMS 1-4 3.5.2 Education (examples) Sleep biology Split-sleep schedules Sleep hygiene Caffeine Napping Nutrition Exercise Sleep strategies Stress/anxiety management Management Crew Families Healthcare providers 43% of surveyed companies not using CEMS, perhaps some other programs, 83% of crew had CEMS training/update programs to address split sleep and 100% crew training and training ongoing yearly 2-3 3.5.3 Stress Management Management Crew Families Healthcare providers 28% of companies surveyed had a program/100% to have program, clear guidelines for a program 1-2 3.5.4 Commuting Management Crew Drivers, hotel rooms/even if being driven crew is probably still awake 1-2 3.5.5 Fatigue Reporting/ Fitness for Duty Policy makers Management Crew 61% of companies have system/100% to have system 1-2 3.5.6 Wellness Program Management Crew Families Healthcare providers Health screening for licensure/ongoing health and wellness programs 2 3.5.7 Registered Medical Examiners Management Policy makers NA/need for consistency 2-3 3.5.8 Sleep Disorders Screening Management Crew Families Healthcare providers NA, some companies screening/all at-risk crew to be screened 1-4 3.5.9 Monitoring and Review of Practices Management Policy makers Crew 4% of surveyed companies currently monitor/100% of companies to monitor 3 3.5.10 Nutrition Management Crew Families Healthcare providers Diet plans, education/ encouragement similar to smoking cessation 2 3.5.11 Exercise/Physical Activity Management Crew Families Healthcare providers Exercise equipment available/is it encouraged or used 1-2 (continued on next page)
From page 66...
... 66 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry In addition, where applicable as part of the current practice the research team also provides a brief summary of the outcome of the assessment conducted as part of this project that was used to support each proposed practice. 3.5.1 FRMS Description Each company should have an FRMS that covers all aspects of their operations and is embedded within an overall SMS.
From page 67...
... Findings and Application 67 of an FRMS is seen as the latest "fad" for advising all workers in a company about a new best practice, it will not be sustainable. There is a clear and consistent need to change the "culture" of much of the industry whereby fatigue management and obtaining sufficient and high-quality sleep becomes a standard operating procedure (SOP)
From page 68...
... 68 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry This is a very timely recommendation since the IMO is in the process of updating its guidelines on managing fatigue. Implementation Readiness/Plan/Considerations • Implementation Readiness Level: 1–4 The research team considers the readiness level for this particular best practice to be a Level 3 for most companies.
From page 69...
... Findings and Application 69 It would be preferable that there be a minimum standardized education curriculum or modules provided that are consistent across the industry. This should also be supplemented with additional education that is appropriate for different groups within the industry (e.g., management, crew, and families)
From page 70...
... 70 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry new educational programs include tools to address differences in generational learning strategies, particularly since the safety critical positions tend to be held by those who are older and have more experience. While deck crew are also at risk of fatigue-related accidents, the barriers to good sleep are likely to be quite different than those for the wheelhouse crew.
From page 71...
... Findings and Application 71 A specific practice related to stress is proposed since results from the current project suggest that stress in various forms negatively influences sleep duration. For example, stress related to health was associated with a short sleep duration.
From page 72...
... 72 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry A major consideration is the source of the stress/anxiety. If the stress is a result of organizational or operational factors, then stress management techniques may well be able to help a crew member deal with the stress.
From page 73...
... Findings and Application 73 (typically those on the 12:12 schedules) ; the other is for those crew who may commute less often on their way to and from home on a longer rotation on the vessels 7–30 days (twice per rotation on and off the boat)
From page 74...
... 74 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry tug/towboat/barge industry. It would just be a matter of formalizing them into the FRMS and education programs.
From page 75...
... Findings and Application 75 Some companies reported that their captains have the authority to monitor rest times and provide additional rest where necessary; another reported have a "floating" crew member who could cover when necessary. The research team also interviewed managers from companies that had open water operations and, in these cases, companies had crew report whether they were working or resting in 15-minute increments across the day on a spreadsheet, although it was unclear from the interview what they did with this information if crew members reported not sleeping or what the criteria were for intervention.
From page 76...
... 76 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry reporting; for example, changing schedules, sending crew for health screens or treatment, and being prepared with replacement crew. 3.5.6 Wellness Program Description Provide access to wellness programs that promote physical and mental health within the industry.
From page 77...
... Findings and Application 77 • Prevent work-related illness and injuries -- for example, control typical workplace hazards and provide adequate sleeping quarters. • Reduce work-related stress -- for example, encourage social support between workers, and work-family balance.
From page 78...
... 78 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry The AWO and one of its working groups on Mariner Licensing & Medical Standards, in collaboration with the NMC, has developed recommendations for both companies and mariners. The recommendations of the AWO working group for companies can be found at: http://americanwaterways.com/sites/default/files/Best%20Practices%20Companies.pdf Other Industries.
From page 79...
... Findings and Application 79 an individual could choose to be screened and treated based on self-interest, given the scientific evidence and consensus of the medical community for the benefits to health and well-being of addressing sleep disorders. Current Practice and Improvements Tug/Towboat/Barge Industry.
From page 80...
... 80 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry fmcsa.dot.gov/NRPublicUI/documents/OSA%20Bulletin%20to%20MEs%20and%20Training %20Organizations-01122015.pdf)
From page 81...
... Findings and Application 81 Having data on whether OSA is a factor linked to safety in the tug/towboat/barge industry would be useful, but may be difficult to get since there does not appear to be systematic monitoring or reporting. Implementation Readiness/Plan/Considerations • Implementation Readiness Level: 1–4 The readiness level for this particular best practice could be considered to range from 1–4 depending on how it is to be implemented.
From page 82...
... 82 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry watch were more likely to be at high risk for OSA (51.3%) than captains/front watch (36.4%)
From page 83...
... Findings and Application 83 space is available, the pilot is able to work the longer hours, which seems counterproductive to the intent of the original rule. Another example from the aviation industry occurs when flight operations go outside the current HOS rules.
From page 84...
... 84 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry little has been done to develop test paradigms that might help workers optimize the schedule of their eating to work in tune with the timing of their internal biology rather than against it. 3.5.11 Exercise/Physical Activity Description Encouraging physical activity and providing the resources, both on and off the vessel, to exercise.
From page 85...
... Findings and Application 85 are overweight, this may make it more challenging for them to exercise; they may need to be provided with access to personal trainers to build exercise programs tailored for them and their physical needs. 3.5.12 Fatigue Modeling Description Using scientifically validated models to predict fatigue/risk/performance levels based on work schedule and the amount and timing of sleep could be a useful tool for the tug/towboat/barge industry to identify and manage fatigue risk.
From page 86...
... 86 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry For implementation of this practice, there would need to be some guidance on which models/ program would be acceptable and consideration as to whether further validation of these models needs to be undertaken with schedules that require more than one work/rest interval per 24 hours in mind. In addition, the various models require different inputs.
From page 87...
... Findings and Application 87 Other considerations include simple things such as determining the cost effectiveness of purchasing 100 mattresses for $300 each or a better-quality mattress at $1,500 each. The $300 mattress may be cheaper initially but need to be replaced more often so in the long run costs more.
From page 88...
... 88 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry really valid when comparing a two-watch versus a three-watch system. A more in-depth analysis of the data in the cited Harma et al.
From page 89...
... Findings and Application 89 or less sleep over 24 hours compared to a square 6:6:6:6 watch given that the sleep opportunity during the second rest period of an 8:8:4:4 watch is only 4 hours. Other Industries.
From page 90...
... 90 Enhancing Sleep Efficiency on Vessels in the Tug/Towboat/Barge Industry high levels of attentiveness and reducing fatigue would result in crew members making a better attempt at obtaining more sleep using the anchor-sleep/nap-sleep strategy. The use of anchor sleep/nap sleep as a best practice is considered at a Level 1, because well over 90% of crew seem to already adopt this practice.
From page 91...
... Findings and Application 91 Current Practice and Improvements Tug/Towboat/Barge Industry. While it seems that missed sleep opportunities are rare (introduction to Section 3.3)

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