Safety watchkeeping on GMDSS ships
The OOW should normally be in possession of a General Operator's Certificate. For ships operating only in GMDSS Area Al a Restricted Operator's Certificate is sufficient. The OOW will be responsible for ensuring compliance with the radio watchkeeping requirements of SOLAS, the ITU Radio Regulations and any local watch keeping rules.
VHF watchkeeping
The VHF watch keeping range is 20 to 30 nautical miles, depending upon antenna height. All ships must keep a continuous watch on:
· DSC Channel 70 (156.525 MHz;)
· Channel 16 (156.8 MHz) when practicable;
· Channel 13 (156.650 MHz) when practicable.
MF (300 - 3000 kHz) watchkeeping
Medium frequency (MF) broadcasts will typically have a R/T range of between 150 and 250 nautical miles by day and a DSC range of 600 to 700 nautical miles. Reception range will be greater at night. Ships must keep a continuous watch on:
· the NAVTEX frequency 518 kHz, when in an area where the service is provided;
· the DSC frequency 2187.5 kHz;
HF (3000 kHz - 30 MHz) watchkeeping
High frequency (HF) broadcasts have an unlimited range. Ships fitted with HF must keep a continuous watch on:
· the DSC distress frequency 8414.5 kHz;
· at least one of the frequencies 4207.5, 6312, 12577, 16804.5 kHz, as appropriate to the time of day and the position of the ship.
Satellite watch keeping
Ships fitted with a ship earth station (SES) must keep a continuous watch on the satellite appropriate to the ship's position. The range of satellite broadcasts is unlimited (except polar regions).
Maritime safety information
Maritime safety information is defined as navigational and meteorological warnings, meteorological forecasts and other urgent safety related messages broadcast to ships.
