What is the legal blood alcohol concentration (BAC) limit for drivers over 21?

The legal blood alcohol concentration (BAC) limit for drivers over the age of 21 is set at 0.08%. This standard is established to help ensure safety on the roads, as research has shown that a BAC at or above this level substantially impairs a person's ability to operate a vehicle safely. At this concentration, drivers suffer a decrease in coordination, judgment, and reaction times, increasing the likelihood of accidents.

The choice of 0.05% is below the legal limit, and while some jurisdictions may impose lower limits for specific groups such as commercial drivers or novice drivers, it does not apply to all drivers over the age of 21. A BAC of 0.10% is above the legal limit, and being over this threshold may lead to harsher penalties and increased risks associated with impaired driving. Finally, a BAC of 0.00% represents a complete absence of alcohol, which applies in certain situations, such as for novice drivers or under specific restrictions, but it is not the general legal limit for drivers over 21.