Give your boat a Maritime Mobile Service Identity

If your boat has a dedicated marine radio, GPS or AIS, your boat systems are not complete until you also have a Maritime Mobile Service Identity, or MMSI. The nine-digit MMSI uniquely identifies your vessel, which is crucial in the event of an on-the-water emergency.

“Each boat is unique. Beyond having a physical name that can be seen up close, each deserves to have its own MMSI that can be ‘seen’ and hailed from a distance,” said Gene Danko, who manages the MMSI program for United States Power Squadrons, America’s Boating Club. “If your boat has a dedicated marine radio, GPS, or AIS, your boat systems are not complete until you also have an MMSI.”

How does an MMSI work

Modern VHF marine radios feature Digital Selective Calling for routine operations and automated distress hailing. A DSC transmission includes four data items: the MMSI, latitude, longitude and time of fix. From this data, search and rescue controllers can identify who you are, where you are, and when you are there. They can apply set and drift calculations to vessels in high wind/current situations, helping rescuers zero in on your position with remarkable accuracy, reducing rescue times from hours to minutes in most cases.

However, your radio must be programmed with your MMSI to use these features. If you boat in waters monitored by the U.S. Coast Guard, be sure all onboard equipment capable of transmitting and receiving digital signals has your MMSI programmed. You should also include your MMSI in your float plan. Even if you don’t boat within the Coast Guard’s coverage zone, emergency calls will be detected by any boats within range, greatly improving your odds of survival wherever you boat.

How to program your MMSI

Programming your radio with an MMSI is easy. Read the instructions that came with your radio, have your MMSI certificate in hand, and check your entry as you go. If you have an older radio, take extra care. Some older units limit the number of times you can enter data before having to return your unit to the manufacturer or authorized agent for reprogramming. The newest radios on the market can be reprogrammed by the operator.

Watch America’s Boating Channel’s MMSI video to learn how using an MMSI can help you communicate and take the “search” out of search and rescue. Discover how to get an MMSI and the best way to program your equipment. Hint: It’s with the device’s owner’s manual in hand.

United States Power Squadrons, America’s Boating Club, issues MMSI numbers to US-flagged vessels not subject to Safety of Life at Sea Convention requirements. Most recreational vessels are eligible for this free service. To request your boat’s MMSI, go to usps.org/mmsi.

Top image courtesy of America’s Boating Channel