U.S. Transportation Secretary Ray LaHood on Tuesday announced an immediate ban on text-messaging by drivers of commercial vehicles, including large trucks and buses.

"Today we're sending a strong message: We don't merely expect you to share the road responsibly with other travelers. We require you to do so," Mr. LaHood said at a news conference in Washington.

The ban applies to interstate truck drivers and commercial bus or van operators who carry more than eight passengers. Violations could result in civil or criminal fines up to $2,750, he said.

"We want to make it crystal clear to operators and their employers that texting while driving is the type of unsafe activity that these regulations are intended to prohibit," said Anne Ferro, administrator of the Federal Motor Carrier Safety Administration.

The agency's research shows that drivers who send and receive text messages take their eyes off the road for an average of 4.6 seconds out of every 6 seconds while texting. At 55 mph, this means the driver is traveling the length of a football field, including the end zones, without looking at the road.

Drivers who text while driving are more than 20 times more likely to get in an accident than nondistracted drivers.

The ban generally drew support from the trucking industry, but one group complained that the regulatory process was bypassed.

"We support where they are going, but not how they got there," said Todd Spencer, executive vice president of the Owner-Operator Independent Drivers Association, which represents 157,000 independent truckers.

"Making their action effective immediately bypasses normal regulatory rule-making processes. Those processes allow actions to be vetted for unintended consequences, as well as potential implementation and enforcement problems.."The American Trucking Associations, the industry's 37,000-member trade association, "totally supports" the ban, spokesman Clayton Boyce said. "We'd like to see it extended to automobile drivers on a national basis."

Doing so would require congressional action, or the Department of Transportation could influence state legislatures to enact bans by threatening loss of highway funding, he said.

Mr. LaHood said the department is planning additional measures "that will help us work alongside the law enforcement community, safety advocates, researchers and others to find new ways to raise awareness and bring an end to the terrible dangers posed by distracted driving."

The Obama administration has taken several steps to combat distracted driving since holding a summit on the issue in Washington in September.

Federal employees were prohibited from texting while driving government vehicles in an executive order that took effect in December.

Washington correspondent Daniel Malloy writes the "Pittsburgh On The Potomac" blog exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.