BAC Effects & Impairment Scale.
How blood alcohol levels progressively impact cognitive processing, physical motor reflexes, and vehicle operation safety.
Sub-Perceptual / Normal
Minimal to subtle effects. Heart rate slightly increased, slight relaxation, normal behavior.
- Slight mood elevation
- Normal inhibitions intact
- Standard sensory perception
Low legal risk in most countries, but vigilance and response time are already subtly affected.
Mild Euphoria & Relaxation
Relaxation, mild sense of warmth, increased sociability, and subtle lowering of inhibitions.
- Mild euphoria
- Reduced shyness & increased talkativeness
- Minor loss of fine coordination
Exceeds legal limit in Japan, India, China, Brazil, Poland, Norway. Reaction time slowed by 15-20%.
Impaired Coordination & Judgment
Reduced reasoning, slowed reaction speed, impaired depth perception, loss of peripheral vision.
- Altered judgment and perception
- Exaggerated emotional responses
- Noticeable tracking delay
ILLEGAL TO DRIVE in 90%+ of the world (EU, AU, NZ, CA, UK Scotland). Crash risk is 4x baseline.
Moderate Intoxication
Clear speech slurring, substantial loss of motor control, impaired balance and delayed processing.
- Slurred speech
- Staggering or unsteady gait
- Loss of peripheral vision and glare recovery
ILLEGAL WORLDWIDE. Extremely dangerous. Gross motor control impairment. Crash risk is 10x-15x baseline.
Severe Intoxication
Major motor impairment, severe sensory loss, high nausea risk, total loss of balance, blackout hazard.
- Inability to walk straight
- Difficulty articulating words
- Emotional volatility & confusion
Severe risk of severe collision or fatality. Inability to control a vehicle.
Very Severe / Blackout State
Stupor, severe disorientation, blackout state, pain perception suppressed, vomiting risk with aspiration danger.
- Severe disorientation
- Memory blackout
- Vomiting and loss of physical consciousness
Critical medical danger. Do not operate machinery. Supervise individual.
Critical / Alcohol Poisoning
Life-threatening alcohol poisoning, central nervous system depression, risk of coma or respiratory arrest.
- Loss of consciousness / unresponsiveness
- Hypothermia & slow breathing
- Seizure and coma risk
CALL EMERGENCY SERVICES (911 / 112 / 999 / 108). Immediate medical intervention required.