By Ray LaHood

WASHINGTON -- If you're looking for some of America's safest drivers, its easy to find them behind the wheel of our nations large trucks and buses.

Safe driving is their livelihood and I know that most of them take safety as seriously as we do at the USDOT.

And that applies to talking on a cell phone behind the wheel.

As one commercial driver, Tim Cox, told a Texas news program recently, "If its in the truck while I'm driving I don't answer it; I don't text. It's just too dangerous; you're endangering your life and the lives of others."

But, because of the size of their vehicles and the weight of the loads they carry for us, when drivers of large trucks, buses and hazardous materials lose their focus for even a few seconds, the outcome can be deadly.

So, last week, the Federal Motor Carrier Safety Administration issued a final rule specifically prohibiting interstate truck and bus drivers from using hand-held cell phones while operating their vehicles.

Through the Pipeline and Hazardous Materials Safety Administration, drivers hauling hazardous materials within a state are also included in the ban.

Research from FMCSA shows that using a hand-held cell phone while driving requires a commercial driver to take several risky steps beyond what is required for using a hands-free mobile phone.

Commercial drivers reaching for an object, such as a cell phone, are three times more likely to be involved in a crash or other safety-critical event.

Dialing a hand-held cell phone makes it six times more likely that commercial drivers will be involved in a crash or other safety-critical event.

The new rule -- the next step in an ongoing process -- will save lives and prevent injuries by helping commercial drivers stay laser-focused on safety at all times while behind the wheel.

Ray LaHood is the U.S. Secretary of Transportation.