Actually since 1st July 2002, when the Global Maritime Distress and Safety System (GMDSS) was implemented, 121.5 is only monitored by aviation stations.
Merchant vessels, Coast stations and the RCC no longer monitor and the majority no longer have the ability to transmit on 121.5
The only practical use for 121.5 is for the old generation COSPAS/SARSAT ELT's which are remotely monitored anyway. Once 406Mhz ELT's become mandatory (next year possibly) the frequency will cease to exist in the global distress scene.
So don't sweat it - if you feel the need to transmit on 121.5 then go ahead. After all it's only us listening anyway!
