The United States, Canada and Iraq are among a small handful of countries that have set the BAC level at .08. Most countries in Europe, including Russia, most of South America and Australia, have set BAC levels at .05 to constitute drunken driving.
When Australia dropped its BAC level from .08 to .05, provinces reported a 5-18 percent drop in traffic fatalities.
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The last move from .10 to .08 BAC levels took 21 years for each state to implement.
NTSB recommends lowering blood alcohol level that constitutes drunken driving - U.S. News