Testing your personal locator beacon (PLB)
A Personal Locator Beacon (PLB) is a last-line safety device designed to be activated only in a life-threatening emergency. It is not a communication tool and it is not something you “try out” on the trail. When activated, it sends a distress signal into the international Cospas-Sarsat search and rescue system.
Because a PLB may sit unused in your pack for years, periodic testing is important. However, testing must be done correctly. Improper testing can reduce battery life or interfere with genuine distress monitoring.
A PLB should only ever be activated in live mode when a person is in grave and imminent danger and requires immediate assistance.
Self-testing your PLB
Between manufacturer-recommended servicing and battery replacement cycles, owners can use the built-in self-test function to confirm continued functionality.
Most PLBs include a self-test mode that performs an internal systems check. This typically verifies:
- Battery status
- Transmitter functionality
- GNSS or GPS acquisition capability
The self-test confirms that radio frequency power is being emitted on 406 MHz and, where applicable, on 121.5 MHz. The signal transmitted during self-test is not processed by satellite rescue systems as a real distress alert.
Follow your manufacturer’s instructions carefully. Testing frequency varies by model. Most manufacturers recommend testing no more than once per month.
Every self-test slightly reduces available battery capacity. Over-testing reduces the operational duration of your PLB during a real emergency.
Timing matters when testing
Because the self-test transmits a brief burst on the aircraft distress frequency of 121.5 MHz, it should only be conducted within the first five minutes of each hour.
The Australian and New Zealand 406 MHz EPIRB and PLB beacon standard requires that the 121.5/243 MHz transmission during self-test is restricted to just one second.
There should be no reason for recreational hikers to test their PLB in operational or live mode.
Avoid operational testing
Operational testing means activating the beacon in live distress mode rather than using the built-in self-test function. This type of testing impacts the global Cospas-Sarsat system and Rescue Coordination Centres worldwide.
Operational testing may only occur in tightly controlled circumstances such as:
- Prototype beacon testing
- New beacon model validation
- Search and rescue training exercises
- Cospas-Sarsat ground segment performance testing
Any operational test of a 406 MHz distress beacon requires prior approval from RCC Australia.
Even a brief live activation will be detected by satellite ground stations and may be received by multiple Rescue Coordination Centres globally. The 121.5 MHz homing signal can also be heard by overflying aircraft, potentially affecting genuine distress monitoring and air traffic operations.
For these reasons, live activation testing must never be done casually or “just to see if it works”.
Check battery expiry and servicing
Most PLBs use lithium metal batteries with a shelf life of five to ten years. Check the battery expiry date printed on your device.
Even if the self-test light activates after expiry, this does not guarantee full performance in a real emergency. Replace batteries or service the beacon according to manufacturer requirements before expiry.
If you are unsure about servicing intervals, contact the manufacturer or an authorised service agent.
Keep registration details current
Testing your PLB is only part of the system. Registration is equally important.
Once purchased, your beacon must be registered with the Australian Maritime Safety Authority (AMSA). Registration is free and in some cases mandatory by law.
A registered beacon allows AMSA to:
- Contact your nominated emergency contacts
- Confirm your likely activity
- Gather trip information quickly
- Reduce response delays
Registration is valid for two years and can be renewed online via the beacon registration system or by calling 1800 406 406.
Update your registration immediately if:
- Your contact details change
- Your emergency contacts change
- You transfer ownership of the beacon
Do not wait for expiry to correct outdated information. Incorrect details can delay a rescue response.
Testing is maintenance, not rehearsal
Your PLB is not a device to practise with under field conditions. It is designed for a single purpose: to trigger a coordinated search and rescue response when self-rescue is no longer possible.
Routine self-testing within manufacturer guidelines, checking battery expiry, and maintaining accurate registration details are sufficient for recreational hikers.
A PLB is most valuable when it is maintained quietly in the background, ready for the moment it is genuinely needed.
