More than a million people drive semitractor trailors, and a surprising number say at one time or another they've dozed off behind the wheel - one of out eight, according to the Insurance Institute for Highway Safety.

Now some trucking firms are taking steps to make sure their drivers will stay awake on the road.

Schneider Trucking and Wausau Homes are screening their drivers for sleep apnea.

Its a condition that can lead to hazardous roads, since drivers that are tired often mimic a driver under the influence.

That includes weaving, driving at high speeds and not paying attention to what you're doing.

While its difficult to say how many sleep-deprived drivers lead to accidents or fatalities, the Wisconsin State Patrol says fatigue does play a role in a number of crashes.

The traffic authority's applauding the industry's new efforts, saying it shows care for both their employees and the other drivers taking to the road.