Fatigue Plans Should Be Part Of Risk Avoidance
For years, the inland waterways industry tussled over the “square watch,” the six-hours-on, six-off watch that had long been the practice on the inland waterways instead of the four-hours-on, eight-off sea watches on blue-water vessels. Some thought the square watch was detrimental to sleep and either wanted to replace it with the blue-water watch system or some other system.
Dozens of academic studies and controlled experiments seemed to support first one side, then the other. A 2006 study, for example, found high levels of sleepiness at the end of each six-hour watch but said fatigue could be “masked” by “the high levels of activity required when taking over the responsibility of the [vessel].”
The controversy raged within the industry as well. Not all inland captains or pilots were partisans of the square watch. Blue-water operators and the U.S. Navy, too, studied sleep cycles, since Navy submariners stand a six-hours-on, twelve-off cycle.
But a scientific consensus finally emerged: the fatigue risks of the square watch were no greater overall than those of any other watch- standing system. In fact, some studies—including one study done by the Coast Guard—indicated that the fatigue risks were greater in the blue-water 4/8 watch system.
That is not the same as a finding of no fatigue risk, however. The studies showed that regardless of watch system, most mariners get consistently less sleep than other workers—about 6.6 hours a day, on average. Fatigue has been an element of major maritime incidents.
International Maritime Organization (IMO) rules require mariners to get 10 hours of rest in any 24-hour period, and no less than 77 hours of rest in any seven-day period. One of the daily rest periods must be at least six hours in length.
The American Waterways Operators’ Fatigue Risk Management Working Group just released a long-awaited document titled, “Developing a Fatigue Risk Management Plan; A Guide For Towing Vessel Operators.”
Many of its recommendations are common-sense: provide opportunities for crewmembers to get proper sleep; avoid harsh sounds, lights or smells near sleeping areas; install sound-dampening equipment and “soft floors”; use blackout curtains; empower crewmembers to use stop-work authority when they are fatigued; and ask crewmembers what more can be done to ensure good sleeping.
Beyond obvious measures, the manual urges towing companies to note if and when fatigue is a factor in their near-miss reporting, which many inland companies already practice as part of their Towing Safety Management Systems. It urges companies to designate a “fatigue coach” on each boat or each company division.
Technology has advanced since crew fatigue began to be debated. Wrist devices and apps that measure sleep hours and other medical indicators are now common enough that they can become part of a fatigue management plan, and inexpensive enough that companies or health insurers can provide them to crewmembers if they wish. These apps or devices aggregate sleep data that could potentially be easily accessed and addressed in a weekly crew meeting.
As risk assessment on the inland waterways becomes more and more informed by data, towing operators will find that including fatigue in their risk management plans is good practice all the way around.
