Resources & Services
Blood Alcohol Content (BAC) Level
Blood alcohol content or BAC refers to the amount of alcohol contained in a person's blood. It is measured as weight per unit of volume. A breathalyzer or alcohol detector are scientific instruments that can measure BAC accurately. Typically this measurement is converted to a percentage such as 0.10%, which indicates that one-tenth of a percent of a person's blood is alcohol. Alcohol in the blood travels directly to the brain and affects cognitive functions such as motor skills, resulting in increased risk of injury. The most common and often times significant injury is the risk of a motor vehicle crash when a person drives with too great a concentration of alcohol in his or her system.
In the United States it is illegal to drive with a BAC of 0.08% or higher. On October 1, 1993 the legal BAC limit was reduced from 0.10%. All States have now lowered the legal limit to 0.08%.
Research on the effects of alcohol has found that many important cognitive functions involved in driving (e.g., information processing, decision making, eye-hand coordination) are at least somewhat degraded in many individuals at BACs as low as 0.04%. Although it is not known how much any of these functions contribute to driving, other evidence obtained from carefully designed, case-control studies of drivers involved in crashes indicates that at BACs above 0.08%, the risk of a crash begins to increase sharply
Highest recorded blood alcohol level
In 1995, a man in Wroclaw, Poland, had a car accident. At the hospital, his BAC was determined to be 1.48%. Concerned that their equipment was malfunctioning, doctors also performed five separate lab tests, all of which confirmed the man's blood alcohol content. He died a few days later from wounds from the car accident. Police were baffled as to how an individual could attain such a high blood alcohol. Later, police discussions with his brother in-law revealed that he had "beer bonged" pure grain alcohol allegedly stolen from his place of work, a chemical plant.
Effects of blood alcohol content on thinking, feeling and behavior: