What is an MMSI number and why should I have one for my boat? If you purchased a VHF radio in the past couple of years, it is probably equipped with DSC (Digital Selective Calling). In order to use this function, you must have an MMSI or Maritime Mobile Service Identity number. This nine digit number, assigned free of charge by Industry Canada, identifies your vessel and allows you to send a distress alert to Coast Guard or communicate with other vessels.
Reason #1 is safety. MMSI numbers are mandatory for commercial vessels but they are now available for pleasure craft. With an MMSI number programmed into your Radio (VHF & SSB’s), a description of your vessel and your location is broadcast when your radio’s distress button is pressed and held for five seconds. This information enhances the detail in a Mayday or Pan-Pan call.
Reason #2 is that MMSI numbers reduce clutter on channel 16. DSC VHF’s enable you to create your own phone book of friends by entering their MMSI numbers into My Calling List. If it is a busy summer day and there is a lot of chatter on channel 16, you simply select your friend’s MMSI number and a working Channel (radios vary), and transmit the call request. Your fellow boater would then acknowledge the call by pressing PTT, and his or her radio automatically switches to the selected working channel and the conversation begins. As well, My Call is far more private than everyone hearing your conversation on channel 16.
Reason #3 is AIS. More and more marine electronics include AIS (Automatic Identification System), which is an automatic tracking system developed to enhance plotters and radars in heavy traffic areas. AIS requires an MMSI number and is mandatory on all vessels over 300 tons. AIS identifies you on a plotter and provides vessel details, position, course, speed and heading.
If you have a DSC VHF radio and have not signed up for an MMSI, visit the Industry Canada website.