2.2 Exchange of messages
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Resolutions - Assembly - IMO Resolution A.954(23) – Proper use of VHF Channels at Sea – (Adopted on 5 December 2003) - Annex - Guidelines on the use of VHF at Sea - 2 VHF Communication Procedures - 2.2 Exchange of messages

2.2 Exchange of messages

  2.2.1 When communicating with a ship whose name is unknown but whose position is known, that position may be used. In this case the call is addressed to all ships.

  • Example:

    "Hello all ships, this is Pastoria, Pastoria. Ship approaching number four buoy, I am passing Belinda Bank Light."

  2.2.2 Where a message is received and only acknowledgement of receipt is needed, say "received". Where a message is received and acknowledgement of the correct message is required, say "received, understood", and repeat message if considered necessary.

  • Example:

    "Message: Your berth will be clear at 08.30 hours.

    Reply: Received, understood. Berth clear at 08.30 hours."

  2.2.3 Where appropriate, the following message should be sent:

  • "Please use/ I will use the IMO Standard Marine Communication Phrases".

 When language difficulties exist which cannot be resolved by use of the IMO Standard Marine Communication Phrases , the International Code of Signals should be used.

In this case, the word "INTERCO" should precede the groups of the International Code of Signals.

  • Example:

    "Please use/I will use the International Code of Signals".

  2.2.4 Where the message contains instructions or advice, the substance should be repeated in the reply.

  • Example:

    "Message: Advise you pass astern of me.

    Reply: I will pass astern of you."

  2.2.5 If a message is not properly received, ask for it to be repeated by saying "Say again".

  2.2.6 If a message is received but not understood, say "Message not understood".

  2.2.7 If it is necessary to change to a different channel say "Change to channel ...." and wait for acknowledgement before carrying out the change.

  2.2.8 During exchange of messages, a ship should invite a reply by saying "over".

  2.2.9 The end of a communication is indicated by the word "out".


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