Signal Scoop

EPIRB and PLB care and maintenance are of utmost importance, even though boaters hope to never use them.

The only thing worse than not having crucial safety gear on board is to have it fail at the moment it is needed. This is especially true for EPIRBs and PLBs, both of which are expected to work flawlessly in an emergency, every time, despite minimal maintenance and constant exposure to the harsh marine environment. Make sure you keep your emergency beacon ready, willing and able.

The primary purpose of any emergency signaling device is to pinpoint its location and facilitate rescue within the “golden day,” that first 24 hours following an emergency during which the majority of survivors can (statistically, anyway) be saved. In essence, such beacons take the “search” out of a search-and-rescue mission. An Emergency Position Indicating Radio Beacon (EPIRB) or PLB (Personal Locator Beacon) goes a long way toward accomplishing that goal.



What They Do

When activated, emergency beacons transmit a coded message on the 406 MHz distress frequency, which is then relayed via the Cospas-Sarsat global satellite system and earth stations to the nearest Rescue Coordination Center (RCC). Units that feature built-in GPS can provide a location accuracy of 150 feet or less. EPIRBs additionally transmit a continuous signal on 121.5 MHz, which allows search-and-rescue units to home in on its location using radio direction finders once they are in the vicinity.



The popularity of PLBs has soared in recent years due to their portability and lower costs, so why not just skip an EPIRB altogether and go with something you can wear? While PLBs and EPIRBs work in exactly the same manner, there are a number of differences between them, beyond size. While a PLB transmits a distress signal for a minimum of 24 hours, transmission time for an EPIRB is double that, a minimum of 48 hours. An EPIRB can be configured to automatically deploy and activate in the event of an emergency; a PLB can’t. Category I EPIRBs are designed to float free from a sinking vessel and turn on automatically when they come into contact with water. A Category II rating denotes an EPIRB that is manually activated and deployed.

As to downsides, an EPIRB is registered to a specific vessel, which means you can’t legally take it to use aboard another vessel, unlike a PLB, which is registered to a person. That highlights a desirable feature of PLBs. They are legal for use on both land and sea, so they can accompany owners on any adventure, from exploring the Amazon to hiking a remote mountain pass.




Once the physical inspection is complete, conduct a self-test by following the manufacturer’s instructions. Following the instructions is crucial to ensure your beacon is working properly and to prevent accidental activation. An EPIRB or PLB is allowed to radiate a single burst during a 406 MHz beacon self-test, one specially coded so it is ignored by the Cospas-Sarsat system.

Most EPIRBs have a visible test switch that is springloaded, so it can’t be left on inadvertently and drain the battery. Depending on the unit, a combination of beeps, lights or strobe flashes will indicate its test circuits are operating properly. Many newer EPIRBs and PLBs will show tests and results via an integrated display.

PLBs must be manually activated and some units are not very intuitive to turn on. Routine testing not only serves to confirm proper operation but also provides familiarization with activating the unit in the event of an emergency.

If an EPIRP or PLB is accidentally activated, turn the unit off and cancel the false alert by calling the nearest U.S. Coast Guard station. They will, in turn, contact the nearest Rescue Coordination Center to cancel the alert.

Be sure to thoroughly inspect the exterior of the EPIRB or PLB and also the bracket or housing that keeps it secure. Physical damage to either is reason enough for repair or replacement. Also check the hydrostatic release unit expiration date (near the top of the image on the right), to ensure it is in working order. And since registration is mandatory, find the instructions on the device. (see below)


Testing & Maintenance

EPIRBs and PLBs should be inspected monthly or prior to any extended cruise. When inspecting and conducting any test, exercise extreme caution to avoid inadvertent activation and generation of a false distress signal.

1. Exterior Inspection
Start by thoroughly inspecting the exterior of the PLB or EPIRB for any physical damage: corrosion, cracking, water ingress, etc. Cracks or damage to the case can allow water intrusion and cause the unit to malfunction or fail. If you note any damage, send the unit to an authorized service facility immediately.

If the unit needs cleaning, simply wipe it down with a damp soft cloth. It should go without saying, but here we go: Never clean a PLB or EPIRB with household cleaners, bleach, sanitizers, soaps, gasoline or anything else. Just plain old water.

2. Battery Expiration
Next up, check the battery’s expiration date. It will be displayed on the beacon manufacturer’s label or possibly a separate sticker. Battery life for most units is five years, although some newer models exceed that. The battery must be replaced on or before the expiration date listed, or if the beacon has been activated.

3. Mounting Brackets
EPIRBs are supported in a mounting bracket or housing, so you’ll want to inspect that. Category I EPIRBs should be stowed in an unobstructed location so they can float free when they’re released. Such installations will also have a Hydrostatic Release Unit (HRU) that’s designed to sense water pressure if a vessel sinks and release the mount, allowing the EPIRB to float to the surface. HRUs expire every two years, so note the expiration date.

If the EPIRB has a tether or lanyard, it should be in good condition, neatly stowed and attached to the unit. It should not, however, be attached to the mounting bracket or vessel.

4. NOAA Registration Sticker
Verify the presence of a current NOAA registration sticker. EPIRBs and PLBS must be registered with the national authority in the owner’s home country. Federal law requires that all U.S.-coded EPIRBs and PLBs be registered with the National Oceanic and Atmospheric Administration (NOAA). This registration provides emergency contact information to search-and-rescue organizations, so if your beacon is activated, they’ll know who they’re looking for. It also gives them someone to call and verify that it’s an actual emergency, rather than a false alarm. Knowing that, you need to update any emergency beacon’s registration if any of the information changes or if you buy a used unit. Registration can easily be completed online at beacon.html.

The test switch on EPRIBs is spring loaded, so it can’t be left on and drain the battery, and the burst it releases during a test is coded to be ignored by authorities. Owners need to consult manufacturer instructions to ensure a proper test.


Time For Action

When activated, some EPIRBs must be deployed and floating in the water for their antenna to operate at maximum efficiency. The manufacturer’s instructions will indicate if the EPIRB should be operating afloat or if it can, for example, be kept inside a life raft.

PLBs on the other hand, should be kept clear of the water once they are activated, and they need to be oriented with the antenna pointing toward the sky. Most PLBs do not float, but they typically come with a flotation jacket of some type.

Finally, once you activate it, keep your EPIRB or PLB switched on until you are rescued. Never turn off the unit to prolong its battery life. Doing so can reduce the satellites’ ability to determine your position and could prolong rescue efforts.