Follow us on Social Media

EPIRBs, PLBs, DSCs, and Why Your Boat Needs Them

Written by guest writer Brian Kearin You’re a hundred miles offshore and your boat is rapidly taking on water. You reach for your boat’s VHF and broadcast a desperate mayday call with your position. As you don your lifejacket and crawl into your boat’s life raft you think of that last mayday call you made, did anyone hear it? Did your radio have the range to reach the Coast Guard station on shore? Are there any other boats around who may have heard it?

It’s a scenario we all hope to never find ourselves in. However far too many boaters are almost entirely reliant on their boat’s VHF radio or worse - their cell phone - for emergency communications. While your boat’s radio is a vital piece of equipment, both for regular use and in emergencies, it has its limitations. In the scenario above, range is limited and dependent on there being someone in range who happens to be monitoring the channel you’re broadcasting on. Additionally, each broadcast is done manually meaning you have to actually talk into the receiver on your VHF and while doing so are limited in your ability to perform other tasks simultaneously. Your boat’s VHF has other limitations like the clarity of communications through it and ease of use for those unfamiliar with it like guests.

This isn’t meant as a knock on your boat’s VHF, it is an excellent piece of equipment that all boats should have. However, like any piece of technology, it has its limitations that you should be aware of and in an emergency it pays to have options. The VHF is one option but there are others like EPIRBs, PLBs, and DSC equipped VHFs that offer you additional ways to contact search and rescue personnel and alert them of your situation and provide your location. 

Perhaps you’ve heard of some of these devices and have considered them but since you don’t boat too far offshore you decided you didn’t need them. Or maybe you only boat on lakes and rivers or on inshore waters and think that these devices are only for “big” boats that go offshore and your boat doesn’t need one. 

The reality is it does. Boaters who travel far offshore already know what these tools are, and likely have several of them aboard, they’re not who I’m writing for. Rather I hope to convince you that an EPIRB or PLB is a necessary piece of equipment for everyone on the water, no matter how small your boat or how small the body of water you frequent.

EPIRBs, PLBs, and DSCs - What Are They?

An Emergency Position Indicating Radio Beacon or EPIRB for short is a device capable of transmitting a distress signal on the 406 MHz frequency via satellite and ground based stations. Most modern EPIRBs are about the size of a large shoe and come in one of two formats, manual or automatic activation. Manually activated EPIRBs have a single foolproof switch to flip to activate them while automatic activation is triggered by the unit’s specialized housing being submerged in water. For small boats manual activation is often preferred since automatic activation types require a fixed location to mount and may be accidentally activated by spray. A typical manually activated EPIRB suitable for the majority of recreational boaters can be had for under $500. 

A Personal Locator Beacon or PLB is very similar to an EPIRB in functionality but smaller and less expensive with many options available under $300. Most PLBs are about the size of a cell phone and as the name implies are meant to be carried on you. They have most of the functionality of an EPIRB however they do have less battery life (over 48hrs vs. ~30hrs) due to their smaller size. And also may lack some of the range of a typical EPIRB when it comes to reaching ground based stations. 

In simple terms the difference comes down to what they correspond to. An EPIRB is generally tied to a specific vessel whereas a PLB corresponds to an individual. Both will send out a distress signal to satellites and ground based receiving stations and both will alert search and rescue organizations to your location. 

Digital Selective Calling or DSC for short is not a device in and of itself but rather a feature of most modern VHF radios. DSC works by allowing your boat’s VHF to send a pre-programmed message with the press of a button. As mentioned earlier, manually using a VHF has several shortcomings like the fact that you actually have to be at the unit to communicate and the clarity of communications can be poor especially over extended distances.

For emergency situations a properly set up VHF with the DSC feature enabled is invaluable. Like an EPIRB or PLB it will, with the flip of a switch, send a pre-programmed distress signal to search and rescue personnel. In some ways a DSC equipped VHF is even better since it also broadcasts that same distress signal to all other boaters in range of your boat’s VHF, many of which may even be closer to you than search and rescue organizations like the Coast Guard. 

If your boat has a modern dash mounted VHF unit you have probably seen that it has a red button protected by a clear cover, that button is used to activate the unit’s DSC feature. See below for a link that provides an in-depth guide to setting up and registering the DSC feature on your VHF. Make sure to properly connect the VHF unit to your boat’s GPS device so that it also transmits your location when used. If you need a hand setting things up or want to install a new DSC capable VHF on your boat consult a marine electrician for help.

Which Should You Choose?

To start with, if your boat already has a DSC capable VHF aboard and you haven’t set it up yet, do that first. It’s free and adds a valuable tool to assist you in an emergency. The next question is should you also get an EPIRB or PLB for your boat. My answer is a resounding yes. Both EPIRBs and PLBs operate independently of your boat’s electrical system and can even operate independently of the boat should it sink or capsize. 

Which is right for you depends on the type of boating you do and your budget. For the vast majority of boaters who operate on inland waterways or stay near shore a PLB is a perfectly adequate option. With battery life over 30 hours most modern PLBs are extremely capable devices that will alert search and rescue personnel to your situation and provide them with your location. Some even have text messaging features that allow you to send pre-programmed texts to friends and family and provide tracking options. And a PLB is small enough that you can use it for other outdoor activities like hiking, canoeing, or cycling.

For boaters venturing offshore, an EPIRB is the correct choice. It’s longer battery life and durability makes it the appropriate choice if you plan on operating your vessel far from land. If offshore sailing or fishing is your intent, a PLB can also serve as an excellent backup and provide yet another option in case of an emergency. 

If you’re trying to decide which to buy and aren’t sure, get a PLB. For most boaters it is a perfectly adequate option and its size and versatility allow you to use it for other activities or take it on any other boats you may go on. Research what’s available, technology changes - mostly for the better when it comes to EPIRBs and PLBs. And don’t hesitate to shop around, look for deals at boat shows and similar events, or rebates offered by manufacturers or even your boat’s insurance company. Even if your budget only permits buying used, there are still a lot of great options available. At the end of the day the peace of mind that comes with having more resources available to you in the event of an emergency will be worth the price. Author Bio: Brian Kearin is the founder of BoatEasy a peer-to-peer marketplace startup for the recreational boating community. BoatEasy connects boat owners with businesses and professionals offering products and services to them. Growing up in South Florida Brian quickly fell in love with the ocean and now spends as much time as possible on, or under, the water. Click Here for the guide to setting up a VHF radio with Digital Selective Calling.

Don't forget to subscribe so you will be notified every time a new article is published.


  1. Thanks for this. Cannot be talked about too often.

  2. I was waiting for the part where the author told me why I needed an EPIRB or a PLB for inland water cruising but it never came. I still believe it's overkill unless possibly on the great lakes

  3. All GPS trackers should have the ability to notify the customer of a specific situation if needed in real time. This could be anything from theft of your vehicle to your boat sinking. When understanding how GPS tracking systems send alerts, it is important to understand the flow of information. Fleet Management Solutions


Post a Comment

Popular posts from this blog

Hydrolock - What is it and How to Prevent it. (Written by Captain Frank Taylor)

Boating Maintenance Items That are Commonly Ignored

Do It Yourself - Fixing a Shower Sump on Your Boat