46 CFR § 78.17-15
Steering gear, whistle, and means of communication
April 15, 2021
(a) On all vessels making a voyage of more than 48 hours' duration, the entire steering gear, the whistle, and the means of communication between the bridge or pilothouse and the engine room shall be examined and tested by an officer of the vessel within a period of not more than 12 hours prior to departure. On all other vessels similar examinations and tests shall be made at least once every week.
(b) The date of the test and the condition of the equipment shall be noted in the official logbook.