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How long before starting a safety-sensitive duty period must a commercial driver stop drinking alcohol?
- A.There is no minimum if the driver feels sober
- B.At least 4 hours before performing a safety-sensitive function
- C.At least 30 minutes
- D.At least 1 hour
Correct answer
B. At least 4 hours before performing a safety-sensitive function
Why
Federal rules forbid performing a safety-sensitive function within 4 hours of using alcohol. Feeling sober is not the test, because judgment is affected before most drinkers notice any change in themselves.
Manual topic: Alcohol and Drugs - Prohibitions · From the General Knowledge practice bank (GK-171).