A common benchmark in the United States for determining when a driver is legally drunk is not doing enough to prevent alcohol-related crashes that kill about 10,000 people each year and should be made more restrictive, transportation safety investigators say. The National Transportation Safety Board recommended on Tuesday that all 50 states adopt a blood-alcohol content -LRB- BAC -RRB- cutoff of 0.05 compared to the 0.08 standard on the books today and used by law enforcement and the courts to prosecute drunk driving. Most Americans think that we 've solved the problem of impaired driving, but in fact, it's still a national epidemic, NTSB Chairman Deborah Hersman said. The idea for a tighter standard is part of a safety board initiative outlined in a staff report and approved by the panel to eventually eliminate drunk driving, which accounts for about a third of all road deaths in the United States. NTSB looks to technology to end drunken driving in the U.S. Hersman said progress has been made over the years to reduce drunk driving, including a range of federal and state policies, tougher law enforcement, and stronger advocacy. But she said too many people are still dying on America's roads. The board acknowledged that there was no silver bullet, but that more action is needed at the federal and state levels. In the last 30 years, more than 440,000 people have perished in