Cat I EPIRB features include which combination?

• A. 406/121.5 MHz; Float-free, automatically activated; Detectable by satellite
• B. 121.5/243 MHz; Float-Fix
• C. 406/121.5 MHz; Manually activated
• D. 406/243 MHz; Float-free, manually activated

Answer: (A)

Category I EPIRBs are designed to auto-activate when immersed in water, broadcast a 406 MHz distress signal detectable by satellites, and also emit a 121.5 MHz signal for homing. The combination that matches this setup is 406/121.5 MHz with float-free, automatically activated operation, detectable by satellite. The 406 MHz channel provides the satellite-based alert with a unique ID, while 121.5 MHz helps rescuers later locate you on-scene. The other options miss one or more of these essential elements: they either lack the satellite-detectable 406 MHz signal, rely on manual activation, or use frequency pairs that don’t provide the full Cat I functionality.