Both the EPIRB and PLB work in parallel; Whereas the EPIRB is commonly registered to the vessel and therefore a permanent passenger on board that particular vessel, the PLB is registered to the mariner or user and thus can be mobile, allowing that user to transition safely between sea and land.
When you activate the EPIRB, it will use an internal GPS to determine its latitude and longitude.
Simultaneously, the beacon starts transmitting its distress signal on 406 MHz – It simply transmits its own identification code.
EPIRBs do not need to be programmed with anything else before transmission. The reason for this is that transmitting on 406 MHz means that it is a distress signal. All details about the vessel in distress are retrieved from the database (which is why it’s critical to register all new EPIRBs or ones that you’re given) that the EPIRB is registered with, using the identification code.
Once the GPS position is available, that is added to the transmission so that the beacon eventually transmits its identity AND its position.
If the GPS signal is unavailable for any reason, the space segment can still determine the position of the beacon using multiple satellites.
It is also possible to use these devices without registering them however, alone, the only thing EPIRBS and PLB’s transmit is their own identity number and hopefully their position on the 121.5 MHz and 406 MHz bands. There is no information about the vessel or the people in distress contained within the signal at all. Which is why registering them gives the correct rescue authorities the pertinent information they need for a potential successful rescue.
Per the COSPAS SARSAT International Beacon Registration Database, you’ll need to supply registration details including:
- Beacon identification numbers
- Name of the vessel the EPIRB is assigned to
- Type of vessel
- Maximum number of persons carried
- Identity numbers
- Radio equipment carried
- Name and address of owners
- Telephone, email and contact details of the owners
- The 24-hour emergency contact number of someone who should know the whereabouts of the beacon’s owner
At Norseman International, during a deliver we ensure the vessel is outfitted with an EPIRB. In addition, we carry our own PLBs which provide added insurance for our captains and crew should we be on the move from one vessel to the next.