Emergency transmitters & epirbs

EPIRB is the “ship beacon”: It is designed for the ship and typically transmits an alert via the Cospas-Sarsat satellite system (406 MHz) and supports homing via 121.5 MHz. PLB is the “personal beacon” (e.g., for crew/solo sailors)—also satellite-based, but person-specific. AIS-MOB is designed for “man overboard” situations and transmits locally via AIS (and, depending on the model, additionally via DSC) so that the vessel’s own crew and nearby ships immediately receive a target marker/alarm.

Recreational Boats/Coastal: AIS-MOB on the life jacket plus a clear AIS display on the chartplotter often provides the greatest safety benefit in MOB situations. Offshore/Long-Distance Voyages: EPIRB (vessel) + PLB (person) is a proven combination because it can send an alarm via satellite regardless of local receivers. Commercial/Offshore: Robust, certified systems and special requirements such as ATEX/IECEx are often essential (depending on the application and regulations).

For AIS-MOB, an AIS receiver must be present on board (AIS device or chartplotter with AIS) so that the MOB position appears as an AIS target. For DSC alerting, a DSC-capable VHF radio is required that is correctly configured (MMSI) and ideally receives a current position (typically via GPS/NMEA). The Ocean Signal MOB2 combines AIS and DSC alarms—this is particularly effective when the onboard AIS and DSC radio are properly configured. :contentReference[oaicite:2]{index=2}

Many systems transmit a 121.5 MHz signal in addition to the main alarm, which nearby rescue units can use for bearing determination. This can significantly facilitate the final phase of location if search and rescue teams are nearby. :contentReference[oaicite:3]{index=3}

Yes – proper registration/programming is a key component of operational readiness, ensuring that an alarm can be assigned and handled effectively. In Germany, this is handled by the Federal Network Agency for 406 MHz EPIRBs (including in connection with MMSI/HEX-ID). Check the current requirements and keep the data up to date (contact, vessel, emergency contacts). :contentReference[oaicite:4]{index=4}

EPIRB: Install it so that it is quickly accessible in an emergency and the antenna can radiate freely; install the mount/release according to the manufacturer’s instructions. PLB/AIS-MOB: Ideally, attach it to your body or to the life jacket/harness so that the transmitter actually goes “into the water” with you in the event of a MOB. Ensure secure attachment, prevent accidental activation, and choose a location that is easily accessible even while wearing oilskins or gloves.

Regularly check status indicators and perform self-tests (according to manufacturer’s instructions), keep track of battery life and replacement schedule, and inspect the housing and mount for cracks, corrosion, and secure fit. After heavy exposure to water or salt: rinse the exterior with fresh water and dry it. After activation: handle the device and service it according to the manufacturer’s guidelines (and applicable regulatory requirements).