California Car / Permit practice question · Alcohol & Drugs
For a driver with a commercial driver license (CDL) operating a commercial vehicle, the illegal BAC level is:
Answer choices
- 0.08%
- 0.04%— Correct answer
- 0.10%
- 0.01%
Why this is the answer
It is illegal to drive a vehicle that requires a commercial driver's license with a BAC of 0.04% or higher. That is stricter than the 0.08% limit for most adults. The same 0.04% limit applies when you are driving a passenger for hire. The 0.01% figure applies to drivers under 21 and anyone on DUI probation.
Source: California Driver Handbook — Alcohol and Drugs
Content reviewed against official driver handbooks · August 12, 2026
More Alcohol & Drugs questions
- Driving after using cannabis (marijuana) in California is:
- For a driver of any age who is on DUI probation, it is illegal to drive with a BAC at or above:
- Prescription and over-the-counter medicines:
- For a driver 21 years or older, it is illegal to drive with a blood alcohol concentration (BAC) at or above:
- According to the BAC table in the California handbook, what lowers your blood alcohol concentration after you drink?