At what bac do an average person's reflexes and alertness begin to decline?

BAC refers to the blood alcohol content found within the body when a person is intoxicated. The levels at which alcohol reacts within the body is influenced by many factors.

General studies have provided that with 0.06 - 0.10 BAC, a person’s reflexes are declined. As the person continues to drink and reaches a 0.11 - 0.20 BAC levels, he/she may now experience a decline in his alertness or reaction time.