EPIRB Category 1 vs 2 Features Explained

There are primarily two types of EPIRBs that you should be familiar with: Category 1 EPIRBs and Category 2 EPIRBs.

The key difference between Category I and II EPIRBs is the method by which they are deployed.

Category I EPIRBs are housed in a bracket that automatically releases the beacon when submerged (usually between 1.5 to 4 meters depth), should your vessel sink. They can also be deployed manually and are typically mounted in a location that facilitates both automatic and manual release.

Category II EPIRBs require manual release, meaning you need to physically deploy the EPIRB yourself. They can also be automatically or manually activated.

FeatureCategory ICategory II
ActivationAutomatic or manualAutomatic or manual
DeploymentAuto-release bracket (float-free) or manualRequires manual release
Designed forCommercial vessels, serious offshore boatersCoastal boaters

Activation vs Deployment

You must know two further terms before buying an EPIRB: activation and deployment.

The activation method is the physical way an EPIRB is turned on so that it can start to signal distress. It can be auto or manual and you absolutely must know how yours works!

The deployment method can also be called the release method. It’s the way your device is freed from its housing or cradle. Again this can be done automatically or manually.

Category 1 EPIRBs are designed to be deployed and activated either automatically upon submersion in water or if the vessel sinks, or manually by the user.

These EPIRBs come with a hydrostatic release unit (HRU) which once submerged, releases the EPIRB, allowing it to float to the surface and start transmitting a distress signal.

Category 2 EPIRBs require manual deployment by the user. They can be activated by being placed in water (automatic) or by pressing the activation button.

While they do not float free automatically, Category 2 EPIRBs, once activated, will also transmit distress signals, including a homing signal to assist rescue operations.

Due to their manual nature, it’s crucial to store Category II EPIRBs in a readily accessible location on your vessel, ensuring quick retrieval.

They can be mounted in a bracket or stored within a ditch bag, depending on your preference and convenience.

Considerations for Boating

When selecting a boating EPIRB, you must consider the type that fits your maritime needs while adhering to safety regulations.

Both categories perform the same in terms of operational battery life (minimum 48hrs) and transmission frequency (406 MHz).

You should regularly perform a self-test according to the manufacturer’s instructions. However, be cautious to avoid triggering a false alarm, which can be a serious matter with rescue services.

Testing your EPIRB is a requirement in almost every jurisdiction and is enforced by the USCG in American waters.

Monthly Visual Inspections: You should perform visual inspections of your EPIRB monthly. Check for any physical damages such as cracks on the unit’s housing and ensure that the seal and label information are intact. Also verify that the HRU, if applicable, is not past its expiration date.

Battery Life and Replacement: The battery life of an EPIRB is limited, typically offering 5-10 years of service. You must check the expiration date and replace the battery when necessary, ideally well before the end of its serviceable life.

For Category I EPIRBs, ensure the automatic release function is unobstructed and properly armed. For Category II EPIRBs, check that manual activation mechanisms are readily accessible and operational.

🎓 Note: Prolonged or improper testing can reduce battery life. Follow the monthly EPIRB inspection procedures provided by your device’s manufacturer or authoritative bodies to conduct proper testing.

On average, Category I EPIRBs are typically more expensive than Category II due to the automatic release mechanisms and additional features.

Here is a simplified cost breakdown:

Category ICategory II
Higher initial costLower initial cost
Replacement of HRU every two years (~$100)Without additional automatic components

Modern EPIRBs often come with a built-in GPS receiver, which allows for faster and more precise location tracking when activated.

This GPS functionality pinpoints your exact position, drastically reducing search times.

Category 2 EPIRBs may also include GPS integration; however, it’s generally more common for Category 1 EPIRBs to be more feature-rich.

Frequently Asked

Opting for a Category 1 EPIRB generally requires a higher initial investment than a Category 2 due to its automatic deployment mechanism and the need for a mounting bracket with a hydrostatic release.

Choose a Category 2 EPIRB if you are operating in coastal areas where you can manually deploy it. It is less expensive and will work for you if you ever have to trigger it.

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.