In passenger ships on international voyages this signal must be supplemented by other electrically-operated signals throughout the ship and operable from the bridge.
Kwiinqanawa zabakhweli kuhambo lwamazwe lo mqondiso mawuthathelwe indawo yeminye imiqondiso esebenza ngombane kuyo yonke inqanawa yaye isetyenziswe ukusuka ebrorhweni.