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What does 49 CFR 392.5 (Alcohol prohibition) require?

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Short answer

49 CFR 392.5 requires that no driver shall use alcohol or be under the influence of alcohol within 4 hours before going on duty or operating a commercial motor vehicle, or while on duty or operating a commercial motor vehicle.

The rule says

"No driver shall (1) Use alcohol, as defined in 382.107 of this subchapter, or be under the influence of alcohol, within 4 hours before going on duty or operating, or having physical control of, a commercial motor vehicle" (49 CFR 392.5(a)(1))

No driver shall (2) Use alcohol, be under the influence of alcohol, or have any measured alcohol concentration or detected presence of alcohol, while on duty, or operating, or in physical control of a commercial motor vehicle — 49 CFR 392.5(a)(2).

In plain English

This rule means that drivers cannot drink alcohol within a certain time frame before driving a commercial vehicle, and they cannot drive if they have been drinking. The rule is in place to ensure public safety and prevent accidents caused by drunk driving. If a driver is found to be in violation of this rule, they will be placed out of service for 24 hours.

What to do

§ 49 CFR 392.5 · eCFR ↗Sources retrieved: 8 retrieved CFR sections · 5 X3 obligations

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