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Awake at the wheel: Combating driver fatigue

On the first day we're born, we sleep. Then we sleep just about every day of our lives. For all of us, sleep is the most natural and necessary experience. And yet, it can be the most mysterious, too. There are times when we're exhausted, but the sleep we so desperately want won't come. Times when we sleep for hours, but wake up just as tired and sluggish as we started. Or for a large number of us,

On the first day we're born, we sleep. Then we sleep just about every day of our lives. For all of us, sleep is the most natural and necessary experience.

And yet, it can be the most mysterious, too. There are times when we're exhausted, but the sleep we so desperately want won't come. Times when we sleep for hours, but wake up just as tired and sluggish as we started. Or for a large number of us, times where the simple act of falling asleep turns into a daily battle for weeks, months and even years on end.

No matter what the reason, when we don't spend about a third of the day asleep, our bodies and minds let us know. Heads and muscles ache, the simplest tasks become a chore, and concentration is elusive, if not impossible. We universally respond to lack of sleep with a whole range of symptoms lumped together under the label of fatigue.

It's not just the amount of sleep we miss, but when we miss it that causes problems. We all have an internal clock that regulates when we sleep and when we wake. Whether or not we're willing to admit it, defying that clock, or what's called our circadian rhythms, can trigger any or all of fatigue's symptoms.

Most of us just try to ignore fatigue or power through it after that rare sleepless night, often with the help of caffeine, until we can climb into bed and get the sleep we need to recover. But the modern world with its 24/7 operations and requirements has created a category of people whose sleep patterns are consistently disrupted for days at a time and who are at high risk for the health and safety threats that accompany long-term fatigue.

Doctors and other researchers who study sleep call them shift workers. It's a group that numbers in the millions in the U.S. , according to the Bureau of Labor Statistics, and it includes doctors and nurses, pilots, police officers and construction workers. In trucking, they're called over-the-road drivers.

While everyone acknowledges the productivity advantages of a 24-hr. work force, shifting sleep patterns “also has many inherent risks,” according to the National Sleep Foundation (NFS), a nonprofit organization that supports sleep-related research and education. With shift workers at high risk for “frequent sleep disturbance and associated excessive sleepiness,” NFS says in a report on shift work, “Sleepiness/fatigue in the workplace can lead to poor concentration, absenteeism, accidents, errors, injuries, and fatalities. … People who work in the transportation industry face some of the most serious challenges. They battle fatigue because of their irregular sleep schedules and endure long tedious hours at the controls or behind the wheel. In fact, research suggests that driver fatigue behind the wheel caused by sleep deprivation is one of the leading safety hazards in the transportation industry.”

Ignoring the issue of shift worker fatigue “is reckless and irresponsible when you consider that billions of dollars in yearly costs, thousands of deaths, and some of the most notorious of modern catastrophes such as the failure of the Space Shuttle Columbia and the crash of the Exxon Valdez have been attributed to human fatigue,” the NFS contends.

Beyond societal concerns for safety, long-term sleep disturbances also carry increased individual risks “for a variety of chronic illnesses such as cardiovascular and gastrointestinal diseases,” according to NSF.

Fatigue also depresses the immune system and has impacts on the body's release of hormones and other chemicals that have been shown to have direct links to weight gain and early-onset diabetes, says Todd Dawson, vp of Circadian, a fatigue management company founded by one of the early pioneers in sleep studies, Dr. Martin Moore-Ede.


Compounding the problem for over-the-road truck drivers is their lifestyle. Long hours behind the wheel and days away from home leave little time for exercise. Restricted to truckstops and other roadside facilities with parking for their vehicles, drivers also have limited access to healthy food choices. Those elements combined are prime causes for the high incidence of obesity among drivers. Aside from the generally well-known health issues that come from being overweight, truck drivers are two to four times more likely than the general population to suffer from sleep apnea, a sleep disturbance directly tied to obesity that can interrupt sleep as many as 100 times an hour, according to Dana Voien, president of Sleepsafe Drivers, a company specializing in diagnosing and treating sleep apnea.

So on top of the fatigue risks faced by shift workers, a large number of truck drivers also find sleep apnea reducing the quality of their sleep, adding further to fatigue, says Dawson.

Although determining shift work's contribution is something of a chicken-or-egg question, the actuarial tables show that fatigue and the constellation of health issues that surround it lead to significantly lower life expectancy for the OTR driver, according to Dr. Gerald P. Krueger, an expert in driver fatigue and wellness who has authored a major study on the subject for the Transportation Research Board. And if the driver suffers from sleep apnea, “the risk of early death is doubled,” adds Voien.

Trucking's regulators can't be accused of ignoring the problem of driver fatigue. The federal government introduced hours-of-service (HOS) regulations over 70 years ago in an attempt to ensure drivers received proper rest.

Although it took them a while, six years ago federal regulators updated HOS based on five decades of sleep and performance research. While the old rules let drivers break up on- and off-duty time, the revised rules require drivers to take off 10 consecutive hours in a 24-hr. period on the theory that will allow them seven or eight consecutive hours of sleep. They also require a 34-hr. “reset” period of off-duty time once a driver reaches the 70-hr. limit for their work week.

But no matter how good the research behind them might be, HOS rules can never completely eliminate driver fatigue. HOS rules are “good as a check and balance, but unless they're so incredibly complex as to be unenforceable, you're always going to come up against someone who's within the law, but still experiencing fatigue,” says Dawson.

The rules “are a safeguard to keep drivers from being pushed too hard, but they're not sufficient by themselves,” says Krueger. Even though he believes the new 10-hr. rule is a good step, “it takes more than complying with HOS to manage fatigue,” he says. “Both the quantity and quality of sleep are important. There are five stages of sleep, and you need all five in the right quantity to get quality.”


It all comes back to those fairly inflexible circadian rhythms. A white paper from Circadian, “Evolution of Fatigue Risk Management System,” puts it best, if in somewhat dry academic terms:

“In essence, the concept of hours of service regulation resulted in a prescriptive model that assumed that most of the risk of fatigue could be addressed by simply placing limits on the number of hours worked in a specified time period and providing for a minimum number of hours of rest between work shifts and between blocks of work shifts. The time of day or night of work, or the 24-hour clock timing of work and rest patterns over a period of days, were not part of the equation. …

A Harvard-Cornell team led by Elliot Weitzman, Martin Moore-Ede, Charles Czeisler, and Richard Kronauer created the first integrated human circadian sleep laboratory at the Montefiore Hospital in New York. One of their most influential early studies demonstrated that the brain's circadian clock exerted a strong control over the timing, duration, and stages of sleep. In fact, as Alexander Borbely of the University of Zurich, Switzerland, and Serge Daan of the University of Groningen, Holland, clarified, there were two major interacting determinants of sleep: a homeostatic component related to the time spent awake and accumulated sleep deprivation, and a circadian component related to the time of day of the individual's biological clock.

Because of this circadian regulation of sleep, there was an important difference between a sleep opportunity and the amount of actual sleep it was possible to obtain during that opportunity. ”

By the early 1980s, it became apparent that the underlying assumptions of hours-of-service regulations were severely flawed. The emerging research on the circadian regulation of sleep and fatigue inevitably led to the conclusion that an employee could be fully compliant with hours of service but highly fatigued, or conversely could be non-complaint and fully alert and safe. The most significant factors influencing employee fatigue were determined to be the circadian times of work and sleep opportunity, and the consecutive number of hours awake, and neither of these were addressed by hours-of-service regulations.

Our bodies are subject to two circadian rhythm “lulls” every day between 1 and 4 p.m. and again from about 1 to 4 a.m., Krueger points out. In tests of response times, “they've measured a 5 to 7% performance dropoff during those lulls,” he says. “And if someone is sleep-deprived, add another 5% drop in performance during the day and an additional 10 to 12% degradation during the night. That's an important [drop in response time performance] for a truck driver, far more important than for an office worker.”


Clearly, fatigue is a serious problem for long-haul drivers, and following HOS laws to the letter is not enough to protect them from the risks. But fatigue problems aren't inevitable, according to those who've spent the last few decades studying the issue.

“Drivers can be alert and attentive and avoid fatigue,” says Krueger. “It takes education and training, not just for drivers but for everyone. Dispatchers, fleet managers, safety managers and executives all have a role to play. All parties need to be attentive to the driver's need for quality and quantity sleep every single day.”

It starts with teaching everyone about the basics of sleep management, including the elements of good quality sleep, working within circadian rhythms, and recognizing the signs of fatigue. Since there are individual differences in how much sleep we require and how we handle changes in our sleep schedules, drivers should be responsible for managing and packaging their sleep in ways that best match their particular sleep personality.

“They need to understand how to get that quality sleep, even if they break it up a bit,” says Krueger. “It can be a bit tricky to match HOS requirements to your circadian rhythms, but it can be done. They need to plan to get the proper amount of sleep before a trip, and to avoid going back to work at the wrong time of day after the 34-hr. reset. Most experienced drivers already know that their body may not let them get to sleep at say 5:30 or 6 p.m., but they don't always plan their workday accordingly. Drivers should learn how to use naps, and the proper use of caffeine when it's needed.”

Fleet management's role doesn't stop with driver training and providing a good sleeping environment in the truck's bunk. “The operational side needs to let shippers and receivers know that the fleet is adhering to a good driver fatigue management program and ask them to work with them,” Krueger says. “That means asking shippers to set appointment times for loading and receivers to have some flexibility on delivery times. It means telling them they can't use drivers to overcome their scheduling problems. “

Dispatchers in particular have to be attentive to the driver's need for quality and quantity sleep. “They should understand circadian rhythms and other principals of fatigue management so they know when a driver needs to sleep and set appointments accordingly,” says Krueger.

The carrier's safety department also has a role to play beyond simply training drivers. “The fleet's management has to make a commitment to attending to the health needs of drivers,” he says. “The health of each driver should be monitored, and if there's a problem like sleep apnea, the fleet should be committed to getting the driver diagnosed and treated and back to work.”

In addition to training, Circadian has developed analytical tools for identifying particular drivers at high risk for fatigue-related problems. Using data from driver logs, the company calculates a “fatigue risk score.” Based on its research in sleep and alertness factors affecting transportation workers, it ranks a driver's probability of having a fatigue-related, DOT-recordable truck accident in the next year on a scale of 0 to 100. The scores can then be used to identify problem operations, to target training for those individuals most at risk, and to measure fleet improvement.

The last point is the most important — and most overlooked — when it comes to fleet fatigue management programs, explains Dawson.

“It can't be just a reaction to a crisis, a static program that's put in place and left there,” he says. “It requires continuous monitoring of other metrics like accidents and near misses, and then a commitment to act on that information with new training, changes to facilities or whatever it takes. The whole thrust has to be continuous, progressive improvement with rewards for drivers and managers for results.”


For Krueger, fleets now need to move beyond fatigue management and begin looking at the issue as part of an overall emphasis on driver health and wellness. “Truck drivers work long hours,” he says. “Having good physical fitness allows them to better sustain that workload safely; however, poor nutrition and lack of exercise are the biggest problem” facing most drivers trying to achieve or maintain good fitness levels.

Some fleets have already made major strides in that direction, according to Krueger, establishing programs that give drivers the opportunity to make good choices about eating, exercising and resting, as well as supporting them with targeted medical screening and treatment programs.

It's much more than concern about the risks of driver fatigue, explains Krueger. “There's an aura of excellence at those fleets,” he says. “The culture of the company suggests that the way to maintain its competitive edge is to attend to the drivers' health and wellness.”

Whether you approach it as a health issue or a safety one, fatigue is not an inevitable side effect of driving a truck. It takes an educated and sustained effort on everyone's part, but long-haul truck drivers can stay alert at the wheel if they just get the help they need and deserve.

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