What is the legal blood alcohol concentration limit for drivers over 21 in most states?

The legal blood alcohol concentration limit for drivers over 21 in most states is 0.08%. This standard is widely adopted across the United States as it reflects a level of impairment that significantly increases the risk of being involved in a crash. At this threshold, individuals are considered to have diminished capacity to operate a vehicle safely, which can lead to dangerous driving behaviors such as slowed reaction times, impaired judgment, and decreased motor skills.

Promoting road safety, this limit serves as an important legal guideline to deter driving under the influence, encouraging responsible behavior from all drivers. States may have stricter laws or penalties, but the 0.08% limit is the baseline that applies nationwide for adults.