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Topic 6 · Alcohol, Drugs, and Driving (DUI Laws)

A commercial driver is considered DUI at what BAC level?

Why

The limit is 0.04% for anyone driving a vehicle that requires a commercial license — half the 0.08% that applies to ordinary drivers. (Handbook, Section 9 — BAC Limits.)

Practise this in the real format

Reading one answer is not the same as sitting the test. The simulator runs the first-time adult form: 36 questions, 6 mistakes allowed, 83% to pass.

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Source: California Driver's Handbook (DL 600, rev. 6/2025), the document the DMV writes the real test from. Edited by Fernando Aguilera. Aprobify is not affiliated with the California DMV.

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