Blood Alcohol Concentration

(BAC) *

Typical Effects

Predictable Effects on Driving

.02%

·          Some loss of judgment

·          Relaxation

·          Slight body warmth

·          Altered mood

Decline in visual functions (rapid tracking of a moving target)

Decline in ability to perform two tasks at the same time (divided attention)

.05%

·          Exaggerated behavior

·          May have loss of small-muscle control (e.g., focusing your eyes)

·          Impaired judgment

·          Usually good feeling

·          Lowered alertness

·          Release of inhibition

·          Reduced coordination

·          Reduced ability to track moving objects

·          Difficulty steering

·          Reduced response to emergency driving situations.

.08%

·          Muscle coordination becomes poor (e.g., balance, speech, vision, reaction time, and hearing)

·          Harder to detect danger

·          Judgment, self-control, reasoning, and memory are impaired

·          Concentration

·          Short-term memory loss

·          Speed control

·          Reduced information processing capability (e.g., signal detection, visual search)

·          Impaired perception

.10%

·          Clear deterioration of reaction time and control

·          Slurred speech, poor coordination, and slowed thinking

·          Reduced ability to maintain lane position and brake appropriately

.15%

·          Far less muscle control than normal

·          Vomiting may occur (unless this level is reached slowly or a person has developed a tolerance for alcohol)

·          Major loss of balance

·          Substantial impairment in vehicle control, attention to driving task, and in necessary visual and auditory information processing

* Information in this table shows the BAC level at which the effect usually is first observed, and has been gathered from a variety of sources including the National Highway Traffic Safety Administration,  the National Institute on Alcohol Abuse and Alcoholism, the American Medical Association, the National Commission Against Drunk Driving, and www.webMD.com.