Flight rulesQuestion 58 of 934

What blood alcohol concentration makes it illegal to act as a crewmember of a civil aircraft?

  1. 0.02 or greater
  2. 0.04 or greater
  3. 0.06 or greater
  4. 0.08 or greater
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Correct answer: 0.04 or greater

An alcohol concentration of 0.04 or greater in a blood or breath specimen is prohibited.

Source: 14 CFR Part 91, § 91.17 Alcohol or drugs.

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Questions last reviewed: 18 October 2026