The issue has hibernated in the industry for decades, and regulators are starting to wake up.
In its proposal to begin inspecting towing vessels, the U.S. Coast Guard is asking for comments on the idea of regulating mariners' hours of service. The core question is whether 7.5 to eight hours of uninterrupted sleep per 24-hour period is necessary to operate a vessel safely.
Most scientific research has concluded that it is. Much of the industry, however, maintains the traditional 12-hour workday, with two watches of six hours broken up by a pair of six-hour breaks.
For at least 12 years, the National Transportation Safety Board has stressed the need for stricter regulation to combat crew fatigue. In 2001, the International Maritime Organization (IMO) released 105 pages of guidance to flag states and ship operators, urging them to ensure that crews get enough rest. The document includes a section specifically about tugs.
About 90 percent of adults need a minimum of 7.5 to eight uninterrupted hours of sleep daily to maintain alertness, according to physicians who specialize in sleep medicine. People who work odd, split or irregular shifts run the greatest risk of sleep deprivation because their body's circadian rhythms may not allow them to fall asleep at the allotted time.
With an eye toward preventing casualties, the Coast Guard seeks input from maritime stakeholders on whether it should address fatigue-management systems in regulation. The comment period ends Dec. 9.
"The Coast Guard is considering requirements that would permit crewmembers on towing vessels sufficient time off to obtain eight uninterrupted hours of sleep or at least seven hours of uninterrupted sleep and an additional sleep period in every 24-hour period and the means to prevent the disruption of circadian rhythms," the Coast Guard wrote in its notice.
"Such standards would promote the daily restoration of crewmember cognitive and physiological resources and the protection of crewmember situational awareness and decision-making abilities."
The National Mariners Association and labor unions had presumed that the Coast Guard would include such regulations in its proposed rule for towing vessel inspections, said Richard Block, the association's secretary. Instead, the Coast Guard put the issue off, asking instead for comments addressing the benefits and costs to operators.
"They want to know why have market forces not caused (the industry to require) the minimum amount of uninterrupted sleep necessary to maintain situational awareness," said Steve Oravets, a director with New York-based Local 333 of the United Marine Division. "Are you kidding me? It's because they're saving money!"
Oravets said the six-on, six-off system flies in the face of medical science. Only a three-watch system would enable mariners to get sufficient sleep to operate safely, he said.
American Waterways Operators (AWO) rejects the idea. AWO President Thomas Allegretti said the need for seven or eight consecutive hours of sleep is a myth. Allegretti cites recent research by the National Aeronautics and Space Administration (NASA) stating that two shorter periods of sleep per day are safe for astronauts. AWO is working with scientists at Northwestern University on research that Allegretti believes will establish that mariners can work safely with five hours of sleep plus a 2.5-hour nap. Those researchers will recruit 700 to 800 towing vessel crewmembers to participate in a sleep survey.
"There is a growing body of knowledge on sleep and towing vessels that the Coast Guard failed to mention in its preamble," Allegretti said. "We think there is a sufficient basis for the conclusion that five plus 2.5 equals 7.5, and that 7.5 is equivalent to an uninterrupted 7.5. … You can achieve the same level of rest and the same level of alertness with the split sleep schedule."
Such a conclusion would be â€œa little bit outside of the mainstreamâ€ of established research, said Dr. Anand Gersappe, medical director at the Swedish Medical Center's sleep center in Redmond, Wash.
"Having two different shifts of sleep creates what we call shift work sleep disorder," Gersappe said. "By fooling the system every day working split shifts, these workers tend to be sleep-deprived not only because they are not getting enough hours of sleep but also because their circadian rhythms may not allow them to sleep."
Allegretti said crews need to do better with the time they now get. Many would rather read, watch movies or talk, he said.
"Our guys are spending more than eight hours a day in bed, but their sleep efficiency isn't very good," Allegretti said. "It's not that they didn't have an opportunity to sleep — it's that they didn't take the opportunity to sleep."
Gersappe said, "If you say (five plus 2.5) is the best we can do, it's reasonable to say we're going to have these periods of sleep, but is that time going to be utilized and is the person going to be able to sleep at that certain time?"
If not, the doctor said, "to me, it's an accident waiting to happen."