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Important Audible Signals You Need to Know How to Interpret
Sound signals are used at sea to communicate between ships. For example, they are used to signal a ship?s presence in conditions of reduced visibility, to warn of a change in direction, or?as in our case today?to announce that a ship is passing another. Each situation has its own specific signal.
To produce these audible signals, a foghorn should be used. Some large ships emit their audible signals using a bell or a gong. Some beacons are also equipped with bells.
International Rules
The International Regulations for Preventing Collisions at Sea (IRPCAS) establish the sound signals used at sea so that they can be understood by everyone. Thus, one short blast means you are maneuvering to starboard, and two short blasts mean you are maneuvering to port. However, in this case, another vessel is catching up to us. We must therefore add two long blasts to the short ones to understand the meaning of this signal. Two long blasts and one short blast therefore mean that the vessel intends to pass on the starboard side; two long blasts and two short blasts mean it intends to pass on the port side.
So the answer was: Answer B?he intends to pass me on the port side.
So you understood his signal correctly. To let him know that you heard him and that you?re inviting him to pass you, you can then make a long beep, a short beep, a long beep, and a short beep.
If you're ever unsure about his maneuver, you can signal him with five short beeps.
You can find all the sound signals in the RIPAM. A sound vocabulary that proves very useful in certain situations!
