46 CFR § 131.505
Steering gear, whistle, and means of communication
April 15, 2021
(a) On each vessel expected to be away from shore for more than 48 hours, the master shall examine and test the steering gear, the whistle, and the means of communication between the pilothouse and the engine room 12 or fewer hours before departure. On every other vessel, the master shall do the same at least once a week.
(b) The date of each test and examination and the condition of the equipment must be noted in the vessel's logbook.