Alcohol & Drugs

Study questions with answers

12 sample Alcohol & Drugs questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.

1. 1. A commercial driver loses the CDL for at least how long for a first offense of driving a CMV with a BAC of 0.04 percent or more?

   Correct answer: One year

   Driving a CMV with a blood alcohol concentration of 0.04 percent or more is a first disqualifying offense that costs the CDL for at least one year.

   Source: Minnesota CDL Manual — Part A (Commercial License Disqualifications)

2. 2. If a driver operating a non-commercial vehicle is found with a BAC of 0.08 percent or more, what happens to their CDL privileges?

   Correct answer: The CDL is disqualified for at least one year

   A BAC of 0.08 percent or more in a non-commercial vehicle revokes Class D privileges and disqualifies the driver from CMVs for at least one year.

   Source: Minnesota CDL Manual — Part A (Alcohol Offenses)

3. 3. Which part of the brain does alcohol affect first as BAC rises?

   Correct answer: The part controlling judgment and self-control

   Alcohol first affects the part of the brain that controls judgment and self-control, which can keep drinkers from realizing they are impaired.

   Source: Minnesota CDL Manual — Section 2: Driving Safely (Alcohol and the Brain)

4. 4. Besides alcohol, what does the manual say about drugs that hide fatigue?

   Correct answer: The only real cure for fatigue is rest, not drugs

   Don't use any drug that hides fatigue; the only cure for fatigue is rest, and such drugs may keep you awake without making you alert.

   Source: Minnesota CDL Manual — Section 2: Driving Safely (Other Drugs)

5. 5. When may a driver use a prescription drug and still legally operate a CMV?

   Correct answer: Only if a doctor says it will not affect safe driving

   Use of a drug prescribed by a doctor is allowed only if the doctor has informed the driver that it will not affect safe driving ability.

   Source: Minnesota CDL Manual — Section 2: Driving Safely (Other Drugs)

6. 6. If a CMV driver refuses to submit to an alcohol or drug test, what is the disqualification for a first offense?

   Correct answer: At least a one-year disqualification

   Refusing a required alcohol or drug test disqualifies the driver from operating a CMV for at least one year on a first offense.

   Source: Minnesota CDL Manual — Part A (Commercial License Disqualifications)

7. 7. How long before going on duty is a CMV driver prohibited from consuming any alcoholic beverage?

   Correct answer: Four hours

   You may not drink alcohol while on duty or consume any alcoholic beverage within four hours before going on duty.

   Source: Minnesota CDL Manual — Part A (Alcohol Offenses)

8. 8. How much alcohol can the liver process, meaning only time can sober a person up?

   Correct answer: About one-third of an ounce per hour

   The liver can process only about one-third of an ounce of alcohol per hour, so nothing but time will lower your alcohol level.

   Source: Minnesota CDL Manual — Section 2: Driving Safely (How Alcohol Works)

9. 9. If a first disqualifying alcohol offense occurs while the driver is operating a CMV placarded for hazardous materials, the CDL is lost for at least how long?

   Correct answer: Three years

   A first disqualifying offense while operating a placarded hazmat CMV costs the CDL for at least three years.

   Source: Minnesota CDL Manual — Part A (Commercial License Disqualifications)

10. 10. How does alcohol interact with the effects of other drugs?

    Correct answer: It can make the effects of other drugs much worse

    Alcohol can make the effects of other drugs much worse, so the safest rule is not to mix drugs with driving at all.

    Source: Minnesota CDL Manual — Section 2: Driving Safely (Other Drugs)

11. 11. According to the manual, what really determines how quickly a person sobers up?

    Correct answer: The passage of time

    Only time will sober you up; black coffee, a cold shower, or fresh air will not speed up the fixed rate at which the body removes alcohol.

    Source: Minnesota CDL Manual — Section 2: Driving Safely (How Alcohol Works)

12. 12. Which four abilities does alcohol impair that are critical to driving?

    Correct answer: Coordination, reaction time, depth perception, and night vision

    Alcohol impairs muscle coordination, reaction time, depth perception, and night vision, along with judgment and inhibition.

    Source: Minnesota CDL Manual — Section 2: Driving Safely (Alcohol and Driving)