Even moderate drinking before driving could become illegal if a federal safety panel's recommendation Tuesday is enacted eventually by the states.

The National Transportation Safety Board recommended that states cut their thresholds for drunken driving by more than a third — from a blood-alcohol content of .08 percent to .05 percent — to reduce highway fatalities. A 180-pound man would reach 0.05 BAC by consuming three beers in one hour, according to a Wisconsin Department of Transportation online calculator.

The proposal, among others by the board, faces a long road before, if ever, becoming the law of the land. It took more than 20 years for all the states to act after the NTSB recommended reducing the drunk driving threshold in 1982.

Lowering the blood-alcohol benchmark could reduce the annual drunken-driving death toll of nearly 10,000 lives by as much as 10 percent, the board said.

The NTSB's recommendation even drew lukewarm support from the national president of Mothers Against Drunk Driving, who said the effort would take too long and undercut more effective programs.

MADD President Jan Withers, an Upper Marlboro resident, said her organization's three-pronged campaign could save many more lives. The plan is built around high-visibility law enforcement, ignition locks to prevent convicted drunken drivers from getting on the road and passive technology that measures the blood alcohol content of motorists.

"We want to save as many lives as possible as soon as possible," Withers said. "We respect the NTSB and its research, but it will take 15 to 20 years to change the laws in each state. We're already moving forward on our campaign, and it will happen sooner than what the NTSB can accomplish."

In 2011, the most recent year of federal statistics, 33 percent of Maryland's 485 traffic fatalities involved alcohol, an increase of 2 percentage points over the previous year.

The NTSB also called for higher penalties for first and repeat offenders and arming police officers with technology such as "sniffing flashlights" to detect alcohol. The agency does not have the authority to impose its recommendations on states, but its opinion carries weight with policymakers.

"Most Americans think that we've solved the problem of impaired driving, but in fact, it's still a national epidemic," said NTSB Chairman Deborah A.P. Hersman in a statement. "On average, every hour one person is killed and 20 more are injured."

NTSB studies indicate that at 0.05, depth perception and other visual skills begin deteriorating in some drivers and the risk of having an accident jumps by 39 percent. At 0.08 BAC, the risk of having an accident increases by more than 100 percent.

Most European and South American countries have set BAC levels at 0.05 for drunken-driving charges.

Withers cautioned that the same forces behind the prolonged fight against lowering the BAC from 0.10 to 0.08 are sure to oppose any further changes. Already, the American Beverage Institute, a restaurant trade association, blasted the recommendation as "ludicrous." The Governors Highway Safety Association said it would review the recommendations, but supports the 0.08 level.

In 1982, the NTSB recommended that states reduce the drunken-driving limit from 0.10 BAC. Utah became the first state to lower its limit the following year, but Maryland didn't take the step until 2001, just three years before 0.08 became enacted by every state.

The General Assembly has shown a deep reluctance to pass new laws cracking down on drunken driving. Each year, many bills on alcohol and driving are proposed, but few succeed.

Annapolis lobbyist Bruce Bereano, who has represented alcohol distributors, said a decrease to 0.05 would be "like going back to the Prohibition era."

"Nobody wants drunken-driving accidents," Bereano said. "But 0.08 has worked very well. I assume it will be brought up next session, in an election-year session. It would take hard, reliable data to convince [lawmakers] that the current laws and enforcement are not adequate."

Historically, the highest hurdle for such bills has been the House Judiciary Committee.

Del. Kathleen Dumais, vice chairman of the committee, said that the legislature acted in 2001 only under the threat of the loss of federal highway funds.

Dumais, a Montgomery County Democrat who was not a legislator at the time, said lawmakers will have to examine how the 0.05 standard would be implemented and what the implications would be.

"I do see some opposition." she said.

In the past, proposals to lower the blood-alcohol level have been fought especially hard by restaurant and tavern owners.

Dumais, who served on a 2007-2008 task force on Maryland drunken-driving laws, said she's willing to take a look at the proposal but is not convinced that a 0.05 standard would be a "panacea." She said lawmakers might want to consider other remedies such as stricter ignition interlock laws, tougher penalties and stepped-up enforcement of current laws.

Gov. Martin O'Malley's office referred a question about the proposal to the sate Department of Transportation. Department spokeswoman Erin Henson said the governor's highway safety representative, Motor Vehicle Administration chief John Kuo, is evaluating the recommendation.

"We are focused on making sure that our roads are as safe as possible for Maryland families," Henson said.

Lon Anderson, the chief lobbyist for AAA Mid-Atlantic, said that while there has been a "sea change in how we view drunken driving, moving the needle again on blood-alcohol content will be a major struggle."

"It's the beginning of a national discussion that will include the need to educate the American people, who will have to be convinced this is a beneficial thing" Anderson said. "It's not something that's going to happen today or tomorrow."

Sun reporter Michael Dresser contributed to this article.

candy.thomson@baltsun.com