What is the maximum blood alcohol concentration (BAC) allowed for drivers over 21?

The maximum blood alcohol concentration (BAC) allowed for drivers over 21 is 0.08%. This limit is established to promote road safety and reduce the risk of accidents caused by impaired driving. When a driver's BAC reaches this level, they are considered legally impaired and can face significant legal consequences, including fines, license suspension, and potential jail time.

This standard is based on extensive research that demonstrates how alcohol affects cognitive and motor functions, such as reaction time, coordination, and decision-making, which are critical skills for operating a vehicle safely. The legal threshold aims to balance personal freedom with the responsibility of ensuring safety on the roads for all drivers and pedestrians.