EPIRBs

EPIRB stands for Emergency Position Indicating Radio Beacon. It is a fixed or portable device used on ships, aircraft, and other craft to signal distress and to aid in location and rescue. When activated, an EPIRB broadcasts a digital distress signal on international frequencies to the COSPAS-SARSAT satellite system, which relays the beacon's identity and, if equipped, GPS-derived coordinates to a regional or national Rescue Coordination Centre. Automatic models may activate upon immersion or other sensor triggers; manual models require user activation.

Most modern EPIRBs transmit on 406 MHz and may include an internal GPS receiver that provides precise position data. This improves the speed and accuracy of rescue. Older or non-GPS units may rely on less precise location data. In addition, many EPIRBs also intermittently transmit on 121.5 MHz for near-field homing, which helps rescuers locate a beacon once the vessel is found. There are related devices such as personal locator beacons (PLBs) for individuals and emergency locator transmitters (ELTs) for aircraft.

Regulation and use: EPIRBs are regulated internationally and nationally. Beacons must be registered with the appropriate authority, linking the device to the owner and vessel or individual, to enable rapid follow-up and rescues and to contact the owner after activation. They require periodic maintenance, battery replacement, and annual checks. Activation without due cause can cause unnecessary mobilization; testing is only permitted under prescribed procedures.

Effectiveness: The satellite-based system provides global coverage for sea and remote areas, contributing to faster localization and rescue. Proper registration, maintenance, and awareness of testing procedures are essential to ensure reliability.