WASHINGTON -- Over-the-road bus and truck drivers face fines of up to $2,750 for using handheld phones while driving and suspension or revocation of their commercial driver licenses for repeat offenses, under the new federal regulation that goes into effect Jan. 3.

The regulation, which applies to all commercial interstate drivers, follows the earlier regulation prohibiting texting for commercial drivers.

Employers who allow drivers to use handheld phones will face fines of up to $11,000 under the rule, which the Federal Motor Carrier Safety Administration proposed in December 2010.

"This . . . rule represents a giant leap for safety," said FMCSA Administrator Anne Ferro. "Its just too dangerous for drivers to use a handheld cellphone while operating a commercial vehicle."

Studies have shown that actions like texting and dialing a phone can greatly increase crash risk. Federal safety agencies admit that studies of distracted driving do not clearly prove whether or not talking on a phone creates a risk.

Instead, the agencies determined that it is the action of taking ones eyes off the forward roadway to reach for and dial a handheld mobile telephone . . . that has the greatest risk.

For that reason, the rule also bans reaching for a phone that is out of reach and dialing a phone, but it does not ban hands-free use or using a single button to initiate, answer or end a call.

It also allows a driver to reach for a phone, "provided the device is within the drivers reach while he or she is in the normal seated position, with the seatbelt fastened."

A more significant change the agency made was to remove a proposed ban on phone use while idling. Instead, phone use is banned while operating on a highway, including when temporarily stopping on the road. It does not include stopping on the side of the road.

Another controversial aspect of the rule concerns holding employers liable for drivers phone use even if the employers had taken good faith steps to prevent it.

While FMCSA acknowledged the concern, it declared that "a motor carrier is responsible for the actions of its drivers."