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What is the difference between a PLB and an EPIRB?

In this guide, we will briefly summarise what the difference is between a PLB and an EPIRB, despite being similar in design and function, they both provide a potential lifeline to seafarers.

What is a PLB

A personal locator beacon, or PLB for short, is a personal electronic transmitting device that is designed to alert potential rescuers to a life-threatening situation in the air, on water or in remote areas. When activated, the PLB sends out a signal on either a 406MHz frequency or Local Area System using 121.5MHz, VHF DSC and/or AIS.

Find out more about how a PLB work’s via our guide: What is a PLB?

What is an EPIRB

An EPIRB is an Emergency Position Indicating Radio Beacon, which is a device that is used at sea to alert search and rescue services (SAR) in distress or an emergency. Working in a similar way to a PLB, an EPIRB is installed on vessels and are registered to a specific boat, rather than a person, via the national search and rescue organisation. In most countries, it is mandatory for all commercial vessels to have an EPIRB registered.

What is the difference between a PLB and an EPIRB?

Despite functioning similarly, there are several differences between how a PLB and an EPIRB work and the situations that you would require one.

Firstly, a PLB is a lot smaller in weight and size than an EPIRB as it is designed to be carried by a single person and is registered to the individual rather than to a vessel. Because of this PLBs can be used anywhere in the world at sea or on land, depending on what frequency they operate on, whereas an EPIRB will only be used at sea.

Due to its size, the transmission duration of a PLB is a minimum of 24 hours, whereas an EPIRB will transmit for a minimum of 48 hours and will float in the water. As a PLB is a personal piece of equipment it should ideally be worn on the person or be integrated within the wearer's Lifejacket.

What do Category 1 and Category 2 EPIRBs mean?

Category 1 and Category 2 EPIRBs (Emergency Position Indicating Radio Beacons) are both used to alert search and rescue personnel of a vessel's location in the event of an emergency. Category 1 EPIRBs are manually activated and are typically found in vessels operating in coastal waters or near shore. In contrast, Category 2 EPIRBs are automatically activated when they come into contact with water and are typically found in vessels operating in offshore and deep sea areas.

Category 1 EPIRB benefits:

  • Can be manually activated in the event of an emergency
  • Generally less expensive than Category 2 EPIRBs
  • Has long battery life
  • Easy to install and maintain

Category 1 EPIRB negatives:

  • Not suitable for vessels operating in offshore and deep sea areas
  • Not as reliable as Category 2 EPIRBs

Category 2 EPIRB benefits:

  • Automatically activates when it comes into contact with water
  • Suitable for vessels operating in offshore and deep sea areas
  • More reliable than Category 1 EPIRBs

Category 2 EPIRB negatives:

  • Generally more expensive than Category 1 EPIRBs
  • Shorter battery life
  • More complex to install and maintain

What Are the Rules & Regulations Surrounding an EPIRB or PLB?

Around the world different authorities, impose different rules regarding the mandatory use of a PLB and or EPIRB. In the UK, the MCA has made it mandatory for all commercial vessels of 10m (L) and over to require an EPIRB (though vessels operated single-handed may replace the EPIRBS with a PLB); or All vessels of less than 10m (L) will require an EPIRB or PLB for all crew members.

It is also, mandatory, according to the “The Merchant Shipping (EPIRB Registration) Regulations 2000” that the owner and the operator of every United Kingdom ship shall ensure that every EPIRB carried on the ship is registered with a competent authority.

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