I am new here, but here is a quick synopsis:
EPIRBs float in an upright position to transmit (perform best when floating)
PLBs float so they won’t get
lost, some need pouch to float. (They need to be held out of the water or attached high up on
PFD for best transmission)
EPIRBs transmit for a minimum of 48hrs at temps down to -40C or -20C (Longer in nominal temps)
PLBs transmit for a minimum 24 hrs at temps down to -20C (Longer in nominal temps)
EPIRBs can be manually activated in or out of their bracket or automatically activated when out of the bracket and in the water
PLBs are manually activated
EPIRBs have a strobe light
PLBs are not required to have a strobe (some newer versions have flashing LEDs)
EPIRBs are designed to be mounted in a bracket or carried in a ditch bag
PLBs are designed to be worn or carried on your persons
EPIRBs are registered to the vessel
PLBs are registered to the person and are
legal to be used on land as well
I would also add that if you are out on the boat by yourself, a PLB strapped to your body is better than an EPIRB in a bracket if you go
overboard. If you have competent crew that could activate an EPIRB in your absence, then an EPIRB is the way to go.
Please remember you need to be prepared to survive the
environment you may find yourself in. The further off shore you go, the longer it will take rescuers to get on scene. An EPRIB floating in the water attached by its tether is easier to manage than holding a PLB in the air. I would also suggest that if you have a PLB then find a way to strap it to your life jacket in advance. (Up in the collar bone area) Treading water with one arm up in the air will be very tiresome.
Both are required to be registered with NOAA. It’s quick, easy and free and can be done online athttp://www.beaconregistration.noaa.gov/