Naps may be the ticket for sleepy air controllers
Naptime may be the best thing to incorporate into an air traffic controller's schedule.
Fri, Apr 22, 2011 at 10:49 AM
Air traffic controllers have been suspended or fired recently for sleeping on the job. Research points to a simpler solution: naptime.
After a rash of reports of misbehavior by air traffic controllers in recent weeks – including watching a movie on duty and allowing first lady Michelle Obama's plane to get too close to a military cargo plane – federal Transportation Secretary Ray LaHood announced two firings. One of these was of a controller in Tennessee who "made a bed in the control tower, brought a pillow, brought blankets," LaHood said on the PBS program "Newshour" on April 20. "He's been fired. We're not going to going to sit by and let that kind of behavior take place in the control towers."
LaHood and the Federal Aviation Administration should consider endorsing it instead, according to some experts.
"I think this is a problem with the scheduling system, and should be attacked that way first rather than as a disciplinary problem," said Gregory Belenky, a professor at the Sleep and Performance Research Center at Washington State University in Spokane.
The nature of air traffic control requires someone to work overnight and sleep at unnatural times, however, it possible to mitigate the sleep deprivation that comes with this type of schedule. Naps of 20 minutes or longer have the same minute-by-minute restorative value as a good night's sleep, Belenky said. "It appears it really is total sleep in 24 hours that makes the difference." [Emotions Run Amok in Sleep-Deprived Brains]
In recent weeks, controllers at Ronald Reagan Washington National Airport and Seattle’s Boeing Field/King County International Airport have been punished for sleeping, and officials have made some changes. Locations with only one controller on duty for the midnight shift will get two, and the minimum time between shifts has been increased to nine hours from eight.
But these changes don't address a fundamental problem, Belenky contends: The schedule worked by some air traffic controllers is at odds with human biology. [5 Things You Must Know About Sleep]
While controllers can work multiple schedules, the problematic one is called a 2-2-1 counterclockwise rotation, which compresses a five-shift workweek. On the first two days, the controller works two evening shifts, followed by two morning shifts, and on the fourth day, the controller ends the morning shift in the early afternoon, then returns to work in the evening, after an eight-hour break (now nine hours).
A schedule like this can create problems because it requires controllers to be alert when their bodies want to sleep and to sleep when they are alert. Nearly everyone has a natural, daily cycle of activity and sleep, called our circadian rhythm. When our body temperature is high, we are productive and alert; and later, body temperature drops, as does our performance, when it's time to sleep, according to Belenky. "That’s physiology; it is not something that can be overcome solely by self-discipline and good intentions," he said.
This compressed shift isn't unique to the United States. A study of controllers in New Zealand on a similar schedule found they slept less and less as they progressed through the week. And during the afternoon of the fourth day, most controllers slept an average of 2.2 hours before their night shift. A separate study of New Zealand controllers found that a 40-minute nap taken during the night shift reduced sleepiness.
"Although sleep taken at work is likely to be short and of poor quality, it still results in an improvement in objective measures of alertness and performance," wrote the New Zealand researchers, led by Tracey Leigh Signal of the Sleep/Wake Research Centre at Massey University.
Adding an hour of sleep to air traffic controllers on the final day of their rotation, as officials have done, may help but is not a solution, said professor Hans Van Dongen, Belenky's colleague at the center in Spokane.
Van Dongen recommends that scheduling software be incorporated with existing mathematical models that predict fatigue, to generate schedules that reduce fatigue – perhaps by fitting naps into them.
"Every schedule is not going to be completely fatigue-free, but we can try to minimize the impact of it," he said. He cautions that scheduled naps would need to take into account sleep inertia – the grogginess you feel after waking up.
According to media reports, LaHood has emphasized the need for "personal responsibility" by controllers and said they will not be paid to take naps.
This latter statement strikes Von Dongen as misguided.
"I understand the logic, but at the same time, we pay for all kinds of things that improve safety," he said.
This article was reprinted with permission from LiveScience.
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