What are regulations for placing fire detectors on ships?

General regulation for placing fire detectors

Put at least one detector in each room, storage area, and  hallway. You may need more than one detector per room for those that exceed the manufacturer’s spacing requirements.

For example, if your detector is rated for 30 feet, install detectors so they are evenly spaced with no more then 30 feet between detectors.

• —Place the detector as close to the center of the ceiling as possible when only one detector is required in a room or space. Put at least one detector in each closet, elevator and other enclosed spaces.
• —Place a detector at the top of each flight of stairs
• Place the detectors in the path of the air flow toward the return air duct when air supply or return ducts are present in a room or space.
• — Place all smoke detectors at least three feet from ceiling fans.