Americans, it seems, are chronically sleep deprived. Perhaps not dramatically so, but we're sleepy enough to make the radar screen at the National Institute for Occupational Safety and Health. Research shows that over 30% of workers aged 30-64 are short of sleep.

While the National Sleep Foundation recommends that healthy adults sleep 7 to 9 hours per day, analysis of a recent survey found that 30% of civilian-employed U.S. adults (approximately 40.6 million workers) reported average sleep duration of 6 hours or less per day.

To assess the prevalence of short-duration sleep among workers, the Centers for Disease Control and Prevention analyzed data from the 2010 National Health Interview Survey. NHIS collects information about the health and health care of the civilian population in the United States using nationally representative samples. Questions about average sleep duration, employment status, and industry of employment are asked of randomly selected adults in each family surveyed. For this study, short sleep duration was defined as less than 6 hours of sleep in a 24-hour period, on average.

The reported rate of short sleep in the Transportation and Warehousing sector -- especially those who work nights -- is more than double that of the general population, at 67.9%. The deeper you dig into recently published survey data, the worse it looks for our particular workforce.

Analysis of the 2010 National Health Interview Survey data shows workers aged 30-44 years and 45-64 years "were significantly more likely than workers aged 18-29 years or 65 years or older to report short sleep duration."

Additionally, researchers noted that workers in certain situations were more likely than average workers to report shorter periods of sleep:

- Among all workers, those who usually worked the night shift had a much higher prevalence of short sleep duration (44.0%, representing approximately 2.2 million night shift workers)

- The prevalence of short sleep duration was significantly higher among workers with more than one job (37.0%), and significantly higher among workers who worked more than 40 hours per week (36.2%).

- In addition to the number of hours worked affecting the opportunity for sleep, the timing of hours available for sleep can affect sleep duration through circadian disruption. Attempts to sleep during daylight hours, when melatonin levels decline and body temperature rises, usually result in shorter sleep episodes and more wakefulness.

- A previous study using NHIS data from 2004-2007 reported that the prevalence of self-reported short sleep duration among U.S. workers had increased during the past 2 decades. That study found a high prevalence of short sleep among workers employed in industries likely to have nonstandard work schedules, but those earlier findings were limited by a lack of data on individual workers' shifts.

Safety or Compliance

I don't find it particularly surprising that one-third of the population report getting less than the recommended amount of sleep. Nor do I believe this group poses any great danger to themselves or society in general, though there are risks associated with chronic fatigue.

Short sleep duration is associated with various adverse health effects such as cardiovascular disease or obesity. As well, insufficient sleep can have serious and sometimes fatal consequences for fatigued workers and others around them. For example, an estimated 20% of all vehicle crashes are linked to drowsy driving.

Most of us manage a few nights of short sleep by sleeping in on days off, or by napping when the opportunity presents itself. I get about six hours of sleep on a typical work night, but I have at least one and often two 30-minute naps during the day. I work at home with no boss looking over my shoulder and no clock to punch, so I can nap with impunity.

I also believe that the restorative affects of a brief nap outweigh the temporary loss of productivity. In other words, if I tried to soldier on during my circadian lulls, I'd get less accomplished in the long run than I do by shutting the office door for half an hour and waking up refreshed.

Most workers couldn't get away with napping on the job. Just ask an air traffic controller what Transportation Secretary, Ray LaHood, thinks of napping. We already know the answer to that one don't we? How easy is it to nap under the current HOS rules? Imagine how easy it'll be to nap with an EOBR ticking away beside you and your dispatcher wondering why the truck isn't moving.

I think it would be safe to say that many truck drivers are in that group of 40 million Americans who don't get enough sleep. Just because HOS says you have to take 10 hours off before driving, the rules don't actually require you to sleep. I'd guess that most long-haul drivers are better rested than their local or regional counterparts, because there's little else to do in the cab of a truck in a truck stop parking lot for 10 hours. The other crowd commutes back and forth to work, has to deal with stuff around the house, and all the other interruptions that conspire against a full night's sleep. I'd say that's especially true for local and regional drivers who work nights.

In the summary of their analysis of the National Health Interview Survey, researchers suggest in-depth examinations of work hours and scheduling can guide employers in designing schedules that increase the probability that workers will be able to sleep during their rest times.

Good idea, but we probably won't have any money left over for research after pouring $2 billion into an EOBR mandate.

You can read the summary of the National Health Interview Survey analysis here.