What is the maximum allowable blood alcohol level for a person acting as a crew member of a civil aircraft?

For individuals acting as crew members of a civil aircraft, the regulations establish a strict limit on blood alcohol concentration to ensure safety in aviation operations. The maximum allowable blood alcohol level is 0.04 percent. This standard is set by aviation authorities to minimize the risks associated with impaired judgment and motor skills that alcohol consumption can cause, which is critical for pilots and crew members responsible for the safety of passengers and the aircraft.

This limit reflects the understanding that even small amounts of alcohol can impair cognitive and motor functions, thus increasing the risk of accidents. By enforcing a maximum limit of 0.04 percent, regulations ensure that crew members remain fit for duty and can respond effectively in emergencies. The other options do not align with this standard; thus, they are not applicable.