New numbering schemes are defined by the ITU for
handheld VHF radios and for other maritime devices for special purposes.
The International Telecommunications Union (ITU)
published a draft revision of the Recommendation ITU-R M.585-5 on the Assignment and use
of 9-digit numerical identities in the maritime mobile service.
The current practice to identify ship stations, coast
stations, aircrafts and helicopters in the maritime service, as well as AIS
aids to navigation with a unique Maritime mobile service identity (MMSI) will
SOLAS ships (complying with the International
Convention for the Safety of Life at Sea) and non-SOLAS ships equipped with
automated radio communication systems, including AIS, DSC, and/or carrying
alerting devices of the GMDSS should be assigned MMSI numbers.
Ships carrying marine VHF radio and/or SSB radio with
DSC should be assigned a unique MMSI in the format MIDXXXXXX
where in the first three digits represent the Maritime Identification Digits
(MID) and X is any figure from 0 to 9. The MID denotes the administration having jurisdiction over
the ship station so identified. For calling simultaneously more
than one ship, Group MMSIs are formed as 0MIDXXXXX.
However, other maritime devices for special purposes
will have a 9-digit numerical identity, which is not an MMSI.
A handheld VHF transceiver with digital selective
calling (DSC) and global navigation satellite system (GNSS) should be assigned
a unique 9-digit number in the format 8MIDXXXXX
where digits 2, 3 and 4 represents the MID and X is any figure from 0 to 9. The
MID represents the administration assigning the identity to the handheld
An automatic identification system-search and rescue
transponder (AIS-SART) should use
an identity:970XXYYYY where XX is the manufacturer ID and YYYY is the sequence number. A
man overboard (MOB) device that transmits DSC and/or AIS should use an identity: 972XXYYYY where XX is the manufacturer ID and YYYY is the sequence number. An
emergency position indicating radio beacon-automatic identification system (The
EPIRB-AIS) should use an
identity: 974XXYYYY where XX is the manufacturer ID and YYYY is the sequence number. The
user identity of the EPIRB-AIS indicates the identity of the homing device of
the EPIRB-AIS, and not the MMSI of the ship.
It remains open, whether a marine handheld VHF radio
with DSC and integrated GPS should be assigned the MMSI of the ship in the
format of MIDXXXXXX if it is the only radio
communication device on board or should be assigned a 9-digit number in the
format 8MIDXXXXX if it is moved from vessel to