What is an EPIRB?
An EPIRB is an emergency position-indicating radio beacon. It is a device that can be automatically or manually activated to transmit a distress signal to a satellite. EPIRBs that activate automatically typically have a hydro-static release mechanism that allows the beacon to release from its bracket, float to the surface and start transmitting. The beacon, along with the bracket, has to sink to approximately 3 meters before it can activate. This should be taken into account when mounting an automatic type EPIRB. EPIRBs transmit at either 121.5 MHz or 406 MHz. More information on both frequencies is available under the “Phase Out of 121.5 MHz Satellite Alerting” section below. 121.5 MHz EPIRBs can either be Class A or Class B. Class A EPIRBs can be activated either manually or automatically, Class B EPIRBs can only be activated manually. 406 MHz EPIRBs can either be Category I or Category II EPIRBs. Category I EPIRBs can be activated either manually or automatically, Category II EPIRBs
