WASHINGTON -- The Federal Motor Carrier Safety Administration, which has been working for months on a rule that toughens the current 15-year-old physical qualification requirements for drivers, may be pondering mandatory sleep-apnea screening as part of any new mandate it issues.

While its unclear what the final standard might look like, there are strong indications new drivers seeking their CDL might have to undergo screening for sleep apnea at the medical exam level.

At the same time, the rule might also require that the existing pool of commercial vehicle drivers be monitored by their employers for screening and ongoing treatment -- much like existing drug-testing rules work.

Depending on the severity, drivers with obstructive sleep apnea could still be permitted to work -- if they're in a treatment program.

Obstructive sleep apnea is the increasingly well-known sleep disorder that causes the closing of the airway passage at the back of the throat, leading to cessation of breathing during sleep.

Individuals with obstructive sleep apnea usually are not conscious of their inability to draw a breath, which can occur dozens of times an hour for periods that can be as long as a minute each.

According to the Sleep Center at the University of Pennsylvania, roughly 28 percent of commercial drivers are likely afflicted with some degree of sleep apnea.

The affliction is most common in overweight males with a body mass index of 25 or larger, and a collar size more than 17 inches. Loud snoring, frequent night waking, shortness of breath and, of course, unexplainable daytime fatigue are telltale signs.

As more attention is paid to the problem, motor carriers may end up in legal limbo waiting for concrete federal guidelines while at the same time trying to insulate themselves from overly litigious trial lawyers.

Theres little doubt plaintiff attorneys are sharpening their claws as the dangers of sleep apnea become more familiar. In fact, trial lawyers are using the available obstructive sleep apnea literature -- some which suggests that extremely fatigued drivers could threaten highway safety as much as drunk drivers do -- to their advantage in court.

The safety-related justification for obstructive sleep apnea testing is obvious, but the liability ramification should be just as clear for anyone operating commercial vehicles in the U.S.

A handful of cases have already tested this approach, with varying degrees of success.

Clearly, though, lawyers are increasingly winning judgments by claiming carriers are vicariously liable if their drivers are involved in fatigue-related accidents -- and more so if drivers are diagnosed with obstructive sleep apnea.

"It's kind of a Neverland for carriers because theres enough information out there that suggests this is a problem, so it opens up the question (of liability) if you have such information on a driver and perhaps look the other way," said one attorney.

This is all the more reason to move forward quickly on a federal rule that provides clear procedural guidelines for operators.

That's not to say trial lawyers won't circle around anyway, but a legal road map drawn up by the feds would better protect carriers who practice due diligence.