What blood alcohol content level defines driver intoxication in the United States, Canada, and the UK?

In the United States, Canada, and the UK, a blood alcohol content (BAC) level of 0.08% is the legal threshold that defines driver intoxication for adults. This standard has been established to promote road safety and reduce accidents associated with impaired driving. When a driver's BAC reaches this level, it is considered that their ability to operate a vehicle is sufficiently impaired, which can lead to unsafe driving behaviors.

Law enforcement agencies and courts use this benchmark to enforce laws against drunk driving. It signifies that an individual has consumed alcohol to a level that is deemed dangerous while operating a motor vehicle. In some jurisdictions, there are stricter limits for commercial drivers or novice drivers, but for general adult drivers, 0.08% remains the established legal limit across these countries.