Is it worth keeping a 121.5MHz Personal Locator Beacon?

From 1st February 2009, 121.5MHz beacons should not be used as an initial emergency alerting device. The primary method of electronic alerting will be the 406MHz beacon system.

The COSPAS-SARSAT search and rescue satellites were originally designed to work on the 406MHz EPIRB frequency. However, the satellites have also had the capability to pick up a 121.5MHz signal and relay it to the appropriate rescue authorities.

However, there are some problems:

  • The 121.5MHz signal will not identify the vessel or the owner.
  • The satellite must be in contact with a ground station at the same time as it receives the 121.5MHz signal from the vessel - or the signal will not be relayed.

Because of these limitations - and because ownership of 406MHz EPIRBs has increased dramatically in recent years as prices have fallen, the international organisations who are responsible for operating and maintaining the satellite systems have decided that it is no longer practicable to support the processing of 121.5MHz signals.

So is worth keeping a 121.5MHz Beacon?

YES! what most people do not realise is that 121.5MHz personal locator beacons were only ever really designed to be homing beacons. This means that they help search and rescue aircraft and vessels home-in on your location once they begin looking for you. Because all search and rescue helicopters and lifeboats still have 121.5MHz monitoring equipment on board, a 121.5MHz beacon is still a useful piece of equipment for you to keep in your emergency grab bag.

For independent technical advice about 406MHz EPIRBs, call the Safety Marine technical team on 0870 165 7424 or email Or for further information about the frequency changes, visit:


The Beacon Logo

For the latest marine safety news each month, regulation changes and invaluable practical safety advice, simply submit your email address.