EPIRB vs PLB | Which Do You Need?

When it comes to maritime safety, understanding the differences between EPIRBs and PLBs can be crucial.

The challenge often lies in determining which device is more suitable for your specific needs.

Leveraging extensive research and a deep understanding of maritime safety protocols, I’ve dissected the key differences and similarities for you.

The explanations are both detailed for the experts and accessible for those new to the world of marine safety.

As someone who has spent countless hours on the water, I understand the importance of being prepared for any situation.

EPIRBs and PLBs are two types of marine emergency beacons, each with its own unique features and uses. Let’s look at an overview first.

At a Glance:

1️⃣ EPIRBs (Emergency Position Indicating Radio Beacons) are only used in marine applications and follow an internationally agreed rescue protocol.

2️⃣ PLBs (Personal Locator Beacons) have a wider general use and can be used for marine and land-based emergency notification signals.

3️⃣ EPIRBs are designed to notify of a vessel in distress, whereas PLBs are kept on the individual’s body and notify rescue services of the person’s situation.

4️⃣ EPIRBs and PLBs transmit on the same frequency (406 MHz.), and the chain of rescue notification and coordination is the same. 

🎭 Key Differences

Before diving into the differences between an EPIRB and a PLB, you might benefit from first understanding what an EPIRB is.

If you do already, then the differences between EPIRBs and PLBs are listed below.


The intended use of each device is different in that EPIRBs are solely used in a marine environment, while PLBs are for use on land as well.

This means that PLBs are ideally suited for climbers, extreme sportspeople, hikers, sailors, and even aviation enthusiasts.

Both emergency devices are politically agnostic. This means that all of the nations that have signed the protocol must respond to transmissions. This is irrespective of the relationships between the nations.

Battery Capacity

EPIRBs must continue producing a signal for at least 48 hours, whereas PLBs are only required to transmit for 24 hours.

Activation Method

The activation methods of the systems are different.

Device TypeCategoriesActivation Method
EPIRBsCategory OneAutomatic (when exposed to water) or Manual
Category TwoManual Only
PLBsN/AManual Only

Registration And Subscription Fee

One of the primary differences between EPIRBs and PLBs is who they are registered to.

EPIRBs Are Registered To A Vessel

EPIRBs are registered to the vessel, and if the registration process has been completed properly, the rescuers will be able to source the following information:

  • The country code of the vessel’s registration.
  • The name of the vessel.
  • A description of the vessel type.
  • The vessel’s home port.
  • Other information that is useful to the rescuers.
  • The emergency contact phone details of the vessel that is in distress.

PLBs Are Registered To The Individual

In a marine environment, PLBs are ideally suited for crew traveling on several boats. The information that they provide is as follows:

  • The name and emergency contact details of the owner of the PLB.
  • The name of all of the vessels on which the member travels.
  • The owner’s home address and contact details.

🔲 Similarities

The similarities between the two emergency beacons are listed below.

Distress Signals

For a device to qualify as an EPIRB or PLB in the United States, it must comply with all of the rules and provisions of the COSPAS-SARSAT protocol and the RTCM standards 47 CFR 95.2991.

EPIRBs and PLBs use the same emergency distress frequency of 406 MHz. Additionally, the systems must also transmit a low-powered signal on 121.5MHz.

This allows the rescuers to use direction finders to home in on the signal when they are nearby.

Modern units include an automatic identification system (AIS) signal to communicate with nearby boats.

They also include a strobe light which allows rescuers to identify them when they are within visual range.


Both devices have access to the same three satellite networks.


The COSPAS-SARSAT satellite constellation is placed in a geostationary orbit above the equator.

Medium Earth Orbiting Satellites (MEO)

MEO satellites are positioned in orbits between 1,000 miles and 22,000 miles. 

Satellites included in this category include the following.

  • Galileo (European Navigation Satellite Systems)
  • GLONASS (Russian Navigation Satellite Systems)
  • GPS (Americas GPS Navigation Satellite Systems)
  • BDS is also known as “BeiDou.” (The Chinese BDS Satellite Systems)
  • Weather satellites.

Low Earth Polar Orbiting (LEO)

The satellites operate in non-geostationary low earth polar orbit. This means they move over the earth in a North/South orientation.

When these satellites receive an emergency signal, the systems can cross reference the locations using all the satellites that received the signal and arrive at a very accurate position.

GPS Capabilities

Many EPIRBs and PLBs are equipped with GPS functionality.

When these devices are activated, part of the emergency signal includes a precise (GPS-derived) latitude and longitude of the emergency event. 

If currents move the survivor’s life rafts or lifeboats, this system will continue to update the GPS coordinates as they change.

Newer EPIRBs include a receiver that rescuers can use to notify the survivors that the signal has been received and rescuer services have been activated.

⚖️ Choosing Between EPIRB And PLB

When comparing an EPIRB and a PLB, understanding what a Personal Locator Beacon is can be very helpful.

The choice between each device is a relatively uncomplicated process.

Intended Activities

EPIRBs are intended as single-purpose emergency transmitters for use in a marine environment only. They are registered to the vessel and will be carried in the boat’s ditch bag.

PLBs are registered to the device’s owner and carried on the person’s body at all times (possibly attached to the life jacket.)

PLBS have a wider use than EPIRB and are functional on land or sea. Their multi-use application is very useful for people involved in different activities where it may be needed.

PLBs are also much smaller than EPIRBs and easier to attach to life jackets or clothing.

Being registered to the person means that rescue services can access the individual’s emergency contact details.

This will allow rescue services to be prepared for any known medical issues or other information that may be useful.

Cost Of Each Device

The cost varies by manufacturer; however, PLBs are generally half the price of a category 2 EPIRB.

In turn, a category 2 EPIRB is approximately 2/3rds of the price of a category 1 EPIRB.

Personal Requirements

The most important consideration will be that it must meet your personal requirements.

Recommended CircumstancesPLBEPIRB
Easy to carry from vessel to vessel, suitable if you crew on different vessels✔️
Suitable if you partake in several different activities on land and sea✔️
Recommended if the budget is limited✔️
Required by law✔️
Used offshore or for international voyages✔️
Used on a single vessel✔️

In all instances, a category 1 EPIRB offers superior functionality to a category 2 unit. 

The main benefits of a Category 1 device are as follows:

  • Automatic activation
  • GPS capabilities
  • Newer designed units include an automatic identification system (AIS) signal that communicates to nearby boats.

🔑 Key Takeaways

An EPIRB or PLB is not a “nice to have” device used to impress other boaters. They are an essential piece of kit that may save lives at a later stage.

1️⃣ Even if they are not required by marine regulations, either (or both) of the devices should always be carried.

2️⃣ When activated, both start a series of rescue activities that operate anywhere in the world by all affected countries.

3️⃣ A category 1 EPIRB is the most capable emergency distress beacon, and its use will enable rescue services to accurately pinpoint the location of the event and notify other nearby vessels, which may be able to respond faster.

It’s also worth considering other safety systems like the Man Overboard Location Alert System, which is an offshoot of the PLB family tree.

If you are wondering what to pack in your ditch bag? A PLB and an EPIRB are good starting points.

Safety is not a subject that should be treated lightly, and it is worthwhile to study the subject in depth.

I’m the founder and chief editor here at Sailing Savvy. I spent a decade working as a professional mariner and currently, I mix those experiences with digital publishing. Welcome, and I hope that we can be the hub you need for safe passage.