46 CFR §108.405

1. (a)Each fire detection system and each smoke detection system on a unit must—
   1. (1)Be approved by the Commandant in accordance with 46 CFR 161.002; and
   2. (2)Have a visual alarm and an audible alarm in the pilothouse or at a normally manned control station for the system.
2. (b)Each fire detection system must be divided into zones to limit the area covered by any particular alarm signal.
3. (c)Each visual alarm must—
   1. (1)Have a chart or diagram next to the alarm that shows the location of the zones in the system and that contains the instructions for operating, and testing the system;
   2. (2)When activated show the zone in the system where fire has been detected; and
   3. (3)Be in a noticeable location in the pilothouse or control station.