EPIRB Meaning

The acronym EPIRB stands for Emergency Position Indicating Radio Beacon. These devices form a vital part of safety equipment at sea.

More specifically they fall under the Global Maritime Distress and Safety System (GMDSS) framework within marine communications systems.

This article looks at this in further detail and also brings you up to speed on other related topics and abbreviations.

Technical Specifications

Before I get going it’s worth refreshing your memory on what an EPIRB is as well as how an EPIRB works.

EPIRBs are designed to send a distress signal when you find yourself in a dire maritime situation.

Upon activation, either manually or automatically through water contact, an EPIRB transmits a signal that is detected by the Cospas-Sarsat satellite system.

This signal is vital for search and rescue operations as it indicates your position to the nearest rescue coordination center.

EPIRBs primarily operate on the 406 MHz frequency, which is monitored by satellites and ground stations globally as part of the Cospas-Sarsat search and rescue system.

Additionally, some older EPIRBs may still transmit a homing signal on 121.5 MHz and 243 MHz.

These frequencies are no longer monitored by satellite and are used by search and rescue teams within closer proximity to the beacon’s location.

The integration of a GPS receiver in an EPIRB significantly enhances its capability.

When the EPIRB includes a GPS, it can send a distress signal inclusive of precise coordinates to the satellite network.

This shortens rescue times as the location accuracy is greatly improved compared to non-GPS EPIRBs.

Global Maritime Distress and Safety System

The Global Maritime Distress and Safety System (GMDSS) is a set of protocols designed to ensure rapid and efficient communication in the event of maritime emergencies.

It is a crucial part of safety at sea, relying on various communication systems to broadcast and receive distress alerts.

Integration with GMDSS

Your boat’s safety is significantly enhanced by the integration of equipment like an EPIRB within the GMDSS framework.

This system works in conjunction with the Cospas-Sarsat satellite system to detect and locate distress signals.

When an EPIRB is activated, it transmits a signal that is picked up by the Cospas-Sarsat satellite network. This ensures a quick response to your distress call from search and rescue services.


Here are the differences between EPIRBs, PLBs (Personal Locator Beacon), and SARTs (Search and Rescue Transponder).

EPIRBSpecifically designed for maritime use.Automatically activated when in contact with water or can be manually activated.Typically mounted on a ship and registered to the vessel.
PLBPersonal emergency beacon for individual use in various environments, including maritime and terrestrial.Manual activation only.Carried by an individual and registered to a person rather than a vessel.
SARTAssists in locating a survival craft or distressed vessel by responding to radar signals.Responds to radar interrogation signals with a series of 12 blips, providing a bearing.Carried aboard lifeboats and liferafts.

Registration and Regulation

Registration and adherence to global regulations are crucial when it comes to safety and the effectiveness of rescue operations depends on these aspects.

Importance of Registration

Registration of your EPIRB is mandatory; it links the device to you personally, including your contact information and important details about your vessel.

Once your EPIRB is registered, you receive a unique identifier (UIN), which often includes a HEX ID.

This allows rescue authorities to access details swiftly in an emergency, confirm any false alerts, and expedite rescue efforts.

Global Regulations

The regulations surrounding EPIRBs are internationally recognized and governed by bodies such as the International Maritime Organization (IMO).

They require that all EPIRBs must be properly registered and frequently tested according to their specific guidelines.

It is your responsibility to ensure that your EPIRB complies with these regulations, including maintaining a current registration and having a valid HEX ID.

Non-compliance can lead to penalties and, more importantly, delay rescue services when you need them most.

Frequently Asked

There are primarily two types of EPIRBs: Category I, which is automatically deployed and activated upon immersion in water, and Category II, which requires manual activation.

Once activated, an EPIRB sends a distress signal that is relayed by satellite to the nearest search and rescue authorities. This facilitates a prompt response to initiate a rescue operation. Activation information is vital. More details can be explored through the U.S. Coast Guard’s guide.

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.