EPIRB stands for emergency position-indicating radio beacon.  It is a device that is designed to transmit a distress signal if activated in an emergency.  No matter where you are in the world, an EPIRB sends a signal to emergency responders through a satellite system called Cospas-Sarsat. (COSPAS is the acronym for the Russina, Cosmicheskaya Sistema Poiska Avariynyh Sudov translating as Space System for the Search of Vessels in Distress and SARSAT is an acronym for Search And Rescue Satellite-Aided Tracking)

There are two types of EPIRBs that can currently be used in the U.S. – Category I and Category II. Category I EPIRBs can be activated either manually or automatically while Category II EPIRBs can only be activated manually.  Both Category I and Category II devices transmit a 406 MHz frequency signal.  All boats are required to carry a Category II device.  Some devices also feature an inbuilt GPS system which improves the accuracy of the beacon’s transmitted position.

In February 2009, the FCC phased out the use of another type of EPIRB that transmitted a 121.5 MHz frequency, and these devices may no longer be used, marketed or manufactured in the U.S.

A PLB is essentially the same as an EPIRB but smaller and so can be carried easily in a jacket pocket.

A 406 MHz emergency beacon should only be activated when you are in grave and eminent danger. Most EPIRB activation switches have a test position. This test position allows the entire unit, including electronics, battery and antenna, to be tested without generating a false alarm.

COPSAT system epirb overview
  1. In an emergency, the radio beacon EPIRB is activated manually or automatically.
  2. The EPIRB transmits an “emergency code” and activates the strobe (flash) indicating that it is operating.
  3. The signal is received by a COPAS-SARSAT satellite and sent to the nearest station.
  4. The station computes the location of the EPIRB and decodes the identification code.
  5. The rescue station uses the identification code to determine the type of vessel, its owner, size, and emergency contacts. Rescue Centres are contacted and alerted to start the rescue operation.
  6. SAR agencies locates the EPIRB using the position information accurate.

All beacons must be registered with the relevant authorities and have the New Ocean Wave Duty Officer listed as the first point of contact so we will be able to provide further information to help the Search and Rescue teams to co-ordinate a rescue by using tracking information, knowledge of your boat and assessment of the situation.

During scrutineering we will check that the EPIRB’s battery is in date (and has at least 6 months of battery remaining on it) and that you have supplied us with the correct unique hex code on the unit. We will also check (using the test feature) that it is correct working order and that you know how to use the EPIRB should you need to activate it.

We will also check it’s location.  The main EPIRB should be mounted outside your main cabin and is generally attached to the rear cabin bulkhead facing towards the cockpit.  It should be attached by a mounting bracket and attached to that by the length of line that is attached to the back of the unit.