By Tom Burden
Emergency Position Indicator Radio Beacons (EPIRBs) and Personal Locator Beacons (PLBs) are small radio transmitters, connected to a global government-run emergency network (Cospas-Sarsat), which is used worldwide to alert Search and Rescue agencies in the event of a dire emergency. Personal AIS Beacons (PABs) are devices that are used to notify other boats in a four nautical mile radius of an emergency Man Overboard situation. Used only when all other means of rescue or communication have failed, these emergency beacons can be activated if your boat is in danger of sinking, or if you have a life-threatening accident or medical emergency.
406 MHz EPIRBs are linked to a specific vessel, allowing rescue agencies to look up your emergency information in a database (including name, phone number, vessel type, emergency contact, etc.). When your EPIRB transmits, rescuers know who you are and can phone your emergency contacts to verify your itinerary. Your position is pinpointed to less than a 2-nm radius.
Personal Locator Beacons (PLBs): EPIRBS are intended strictly for marine use, but PLBs, their smaller cousins, can be carried with you just about anywhere. They provide the same worldwide coverage as EPIRBs, and can rescue hikers, kayakers, backpackers, climbers, pilots, river rafters and hunters (among others) as well as boaters. Their battery life (24 hours) is often half that of an EPIRB.
PLBs are not required to float or have a strobe light (but most do), and are manually deployed and activated. Like 406 MHz EPIRBs, PLBs have an additional 121.5MHz homing signal to help planes, helicopters and other rescuers find you. We believe, as do the safety experts, that EPIRBs are for your boat, and a PLB is a “personal” beacon. A PLB is great insurance while exploring away from the mothership in your dinghy, and is a less-bulky EPIRB alternative for any small boat.
Personal AIS Beacons (PAB): These new devices gained FCC approval for use in the U.S. in April, 2012. Personal AIS Beacons are intended to be attached to your life vest and activated if you go overboard or encounter some other emergency while you’re in a dinghy. They use both GPS and AIS (Automatic Identification System) technology to send structured alert messages containing your precise location information to any AIS receiver onboard your vessel and to other AIS-equipped boats or ships that happen to be within a typical four-mile radius. In a crew overboard situation, chances of finding and recovering the casualty are greatly increased, thanks to information given by the PAB, which for the first time shows bearing and distance to the person in the water.
Category I and II: By rule, all EPIRBs must be able to activate and transmit when they are removed from their brackets and immersed. Category I brackets will automatically deploy the beacon when submerged between 3' and 14', while Category II brackets need to have the beacon released manually. Both types can be manually activated either in or out of their brackets.
GPS/EPIRB Combinations: Three types of EPIRBs transmit GPS coordinates to pinpoint your location and reduce the time required for rescue. Some units can interface with an external GPS. Other EPIRBs contain their own receiver and keep transmitting while the EPIRB is operating, without remaining connected to an external GPS. Like other GPS receivers, their position accuracy is 100yd. (instead of 2nm without GPS). The GlobalFix iPRO combines features of both receiver types.
A built-in LCD display gives useful info including self-test results, remaining battery power, operating instructions, transmission bursts and your LAT/LON position. The AquaLink View PLB and GlobalFix iPRO EPIRB are the only beacons with this feature.