What are Radio telephony Procedures as per GMDSS?

Calls to coast station :-

• Calls made on the appropriate working channel whenever possible as indicated in ITU list of coast station or ALRS – Vol-1.
• If working channel is not available then 2182 kHz (MF) or ch-16 (VHF) may be used for primary calling.
• When making a call to coast station on 2182 kHz, the ship station operator should indicate the reason for call and intended working frequency/ channel for subsquent traffic.
• If a CRS in called on the working frequency/ channel, it should normally reply on the same or paired frequency / channel on the same band.
• When calling on VHF working channel the ship stations should indicate channel being used.

Control of traffic :-

• During communications between ships and coast stations the coast station control the working.
• In communications between ships, the called ship stations control the working.
• However if a CRS finds it necessary to intervence in communication between ships, both ship station should abide by instruction from CRS.

Release of Identification:-

1. A station should release its identification at the beginning and end of the transmission.
2. Afterwards as frequent as necessary.
3. In case of long communication, identification should be release at least every 15 minutes.