Carrying a 406 MHz EPIRB aboard your yacht is not the same as being compliant. The two requirements look identical from the dock - there is a beacon in the bracket, it has not gone off accidentally, and no one has asked about it since the last haul-out. But between an EPIRB that merely exists and one that will generate a targeted, co-ordinated search and rescue response in the Torres Strait or the outer Coral Sea, there are registration records, battery dates, hydrostatic release units, and service stamps that need to be checked, updated, or replaced before you clear customs in Cairns. This guide maps each requirement to the passages that make them matter.
How the Cospas-Sarsat System Routes an Alert From Activation to Rescue
When a 406 MHz EPIRB activates, it transmits a digital burst on 406.028 MHz containing the beacon's unique 15-digit hexadecimal identifier - the Hex ID, also called the UIN. That signal is received by medium-earth-orbit and low-earth-orbit satellites in the Cospas-Sarsat constellation and relayed to ground receive stations, which forward the alert to national Mission Control Centres.
Australia's Mission Control Centre (MCC) is based in Perth. It handles alerts originating in Australian waters and in international waters where Australia holds responsibility. On receiving an alert, the Perth MCC cross-references the Hex ID against the AMSA registration database at beacons.amsa.gov.au, retrieves the vessel name, owner details, and emergency contacts, and notifies the Joint Rescue Co-ordination Centre. The entire chain - satellite to Perth to JRCC to tasked SAR asset - moves quickly when the registration data is accurate and current.
When the data is wrong, the chain breaks. An EPIRB registered to a previous owner sends SAR co-ordinators to a person who no longer holds the beacon. An expired emergency phone number wastes the minutes that matter most early in a response. The Hex ID is the only link between a physical beacon and the database - if the registration behind it is stale, the satellite detection means very little.
GPS vs Non-GPS EPIRBs: Why the Position Fix Gap Is a Life-Safety Issue on Remote Passages
This is the specification difference that receives the least plain-language explanation in consumer-facing content, and it is the one that matters most for passages north and east of Cairns.
A GPS-equipped 406 MHz EPIRB embeds the vessel's current coordinates directly in the 406 MHz signal. The Cospas-Sarsat system can deliver that position - accurate to roughly the size of a football field - to SAR co-ordinators within approximately 20 minutes of activation. A non-GPS beacon provides no embedded coordinates. The system instead calculates position by Doppler shift analysis across multiple satellite passes. That process can take up to 90 minutes, and the initial fix may only be accurate to within 5 km.
In the Torres Strait or the outer Coral Sea, a 5 km search radius around an approximate position is a significant problem. A vessel sinking in 35-knot conditions drifts. A crew member in the water drifts faster. The 70-minute gap between the two fix times, combined with the difference between a football field and a 5 km circle, translates directly into SAR fuel burned, assets committed, and time lost before anyone is on scene.
| Beacon Type | Position Fix Time | Transmission Duration | Satisfies Vessel EPIRB Rule |
|---|---|---|---|
| GPS 406 MHz EPIRB | ~20 minutes | 48 hours minimum | Yes |
| Non-GPS 406 MHz EPIRB | Up to 90 minutes, 5 km accuracy | 48 hours minimum | Yes |
| AIS-integrated GPS EPIRB | ~20 minutes plus immediate AIS alert | 48 hours minimum | Yes |
| GPS Personal Locator Beacon | ~20 minutes | 24 hours minimum | No |
Category I vs Category II: Float-Free Deployment and the Hydrostatic Release Unit
All 406 MHz EPIRBs carried in Australian offshore waters must comply with Australian Standard AS/NZS 4280.1:2003. A beacon without that certification cannot satisfy the mandatory carriage requirement for any vessel operating more than 2 nautical miles from shore. Beyond that certification, EPIRBs divide on how they deploy in an emergency.
- Category I (float-free): Mounted in a bracket fitted with a hydrostatic release unit (HRU). When the vessel submerges to between 1 and 4 metres, the HRU triggers automatically, the bracket releases, and the EPIRB floats free and activates. No crew action is required.
- Category II (manual only): Deployed by hand from a bracket or grab bag. If the vessel sinks suddenly - a collision at night, a rapid capsize - no one may be positioned to retrieve and activate it in time.
Queensland Maritime Safety Authority mandates that vessels in Category 1 waters - unlimited offshore waters - carry a 406 MHz EPIRB regardless of vessel length. That applies to any departure from Cairns for Torres Strait, PNG, Indonesia, or the outer Coral Sea. A Category II unit satisfies the carriage rule on paper, but float-free deployment is the only mechanism that guarantees beacon activation if the vessel goes down quickly.
HRU Maintenance: Disposable vs Reusable Units
The HRU is the most neglected component on most offshore yachts. The installation date for a disposable HRU is recorded on the bracket - not on the unit itself. Disposable HRUs must be replaced exactly two years from that installation date. Reusable units, such as the Hammar H20, must be returned to an authorised service agent annually; the service interval is stamped on the unit and a service label must be visible on the bracket.
On older vessels the bracket label is frequently faded, painted over, or missing entirely because a previous owner replaced the HRU without updating the record. If the label is unreadable before departure, replace the HRU through an authorised agent rather than assuming compliance.
AIS-Integrated EPIRBs: The Second Rescue Pathway
An AIS-integrated EPIRB transmits two simultaneous signals on activation. The first is the standard 406 MHz Cospas-Sarsat burst routed through Perth to the JRCC. The second is an AIS distress message on the AIS working channels - classified as Message Type 1 with navigational status 14, accompanied by an 'EPIRB ACTIVE' safety text. That message appears on the AIS display of any vessel within approximately 5 nautical miles as a circle-with-cross symbol, the AIS distress indicator.
The satellite pathway takes time. In the Torres Strait, a rescue helicopter may be based an hour or more away. A vessel already transiting nearby can reach the casualty in 20 to 30 minutes. The AIS signal requires no satellite relay and no JRCC co-ordination - it broadcasts immediately to whatever vessel is close enough to receive it. In a region with significant commercial and fishing traffic, this is a distinct rescue pathway rather than a redundant one. Most content on EPIRBs treats AIS integration as a footnote. It is not. For a remote passage, it is the mechanism most likely to get a vessel on scene while the satellite chain is still working through the alert process.
AMSA Registration at beacons.amsa.gov.au: The 2024 Change and What Still Needs Attention
On 4 November 2024, AMSA removed the two-year registration renewal requirement. Beacon registrations no longer expire. Owners who registered before that date and have a label reading 'Expires 2023' or 'Expires 2024' are grandfathered - their registration remains active. This has created a specific problem across the offshore fleet: boats are carrying beacons with expired-looking stickers that are technically current, but whose registered contact details have not been reviewed since the original registration because the old renewal cycle no longer forces that review.
A registration is only as useful as the contact details behind it. The beacon gets heard. What happens next depends entirely on whether the information in Perth matches the people who can actually respond.
Before every offshore passage, log in to beacons.amsa.gov.au. Confirm vessel name, owner phone numbers, emergency contacts, vessel description, and MMSI. Verify that the Hex ID in the registration matches the Hex ID printed on the physical beacon. This takes five minutes and is the step most frequently skipped.
Departing Australian Waters for PNG, Indonesia, or the Pacific
Cairns is one of a small number of Australian ports where yachts regularly clear out for international destinations. The AMSA registration remains valid and functional in international waters - the Cospas-Sarsat system is global, and the Perth MCC handles alerts from Australian-registered beacons wherever they occur. No additional registration is required before departing for PNG, Indonesia, or the Coral Sea route to the Pacific.
What does need attention: confirm that emergency contacts are reachable internationally, and that the voyage details in the registration reflect the actual planned route if that field is used. When the vessel is sold before or after a passage, the EPIRB registration must be transferred or cancelled at beacons.amsa.gov.au. An alert from a beacon still coded to a previous owner directs SAR co-ordinators to the wrong person, and can delay response to the actual casualty.
Battery Expiry and Why Authorised Servicing Exists
EPIRB batteries carry a 5-year shelf life and must sustain a minimum of 48 hours of continuous transmission from a single activation. PLB batteries need only support 24 hours - one of the reasons PLBs cannot serve as a vessel's primary EPIRB.
Battery replacement on a 406 MHz EPIRB cannot be performed by the boat owner. Unauthorised replacement is non-compliant under AS/NZS 4280.1 and can render the beacon unfit for its purpose. The restriction is not administrative: the replacement process requires resealing the housing to the original waterproof specification and verifying the unit's output against the standard. Only an AMSA-recognised authorised service agent can legally replace the battery and re-certify the beacon. AMSA lists recognised agents on its website; for current servicing fees, contact agents directly. In Cairns, allow at least six to eight weeks before a fixed departure date - agents may need to order specific battery assemblies, and the town is not a major service hub.
PLBs: What Every Crew Member Needs and What PLBs Cannot Do
A Personal Locator Beacon is registered to a person, not a vessel, through the same beacons.amsa.gov.au system using the PLB's Hex ID. Every crew member on an offshore passage should carry one. A PLB worn by someone who goes overboard activates with them regardless of whether the vessel is still afloat - it is the only distress device that stays with the individual in the water.
- PLBs complement the vessel EPIRB - they do not replace it
- Each PLB must be registered individually to the person who carries it
- PLB batteries also carry expiry dates - check the label on every unit before departure
- GPS-equipped PLBs offer the same position-fix advantage as a GPS EPIRB for the individual carrying it
- PLBs transmit for 24 hours minimum, not 48 - critical in a prolonged SAR operation
Testing Without Starting a Search
Self-testing is permitted, but the timing rule is specific. Testing must only be carried out within the first five minutes of any UTC hour. Most manufacturers' self-test sequences activate an LED and an audible tone without transmitting a full Cospas-Sarsat signal to the satellite network. The test confirms internal circuitry, not satellite transmission. A full live test of a vessel-mounted EPIRB is never authorised outside the designated window.
If an accidental activation occurs - a beacon knocked from its bracket, a unit dropped during installation - reporting it is both legally required and straightforward:
- Switch the EPIRB off immediately if this can be done safely.
- Call AMSA's National Distress Alerting System on 1800 641 792 and report the false activation.
- Stand by on VHF Channel 16 in case the Perth MCC or JRCC attempts contact.
- Provide the beacon's Hex ID, your vessel name, your current position, and confirm there is no distress.
- Follow any further instructions from the AMSA operator before resuming normal operations.
Failing to report a false activation is an offence under Australian law. SAR recovery costs can be billed to the responsible party, and a fine may also apply. Check AMSA's current penalty schedule for the applicable figures. The call itself takes under five minutes and AMSA staff handle false activations routinely.
Pre-Departure Beacon Compliance Checklist for Yachts Leaving Cairns
Each item below should be physically checked against the unit or the registration record - not assumed on the basis of the last passage.
- AS/NZS 4280.1:2003 certification: Confirm the marking appears on the EPIRB housing label. A beacon without it cannot satisfy the mandatory carriage requirement.
- Battery expiry date: Read the label on the housing. If the unit is within six months of expiry, book an authorised agent in Cairns now, before fixing your departure date.
- HRU expiry (Category I brackets): Find the installation date on the bracket. Disposable HRUs expire two years from that date. Reusable units must show a current service stamp. If the bracket label is missing, replace the HRU.
- AMSA registration: Log in to beacons.amsa.gov.au. Verify owner name, phone numbers, emergency contacts, vessel name, and MMSI are all current. Match the registered Hex ID to the physical beacon.
- Ownership transfer check: If the vessel was purchased recently, confirm the previous registration has been transferred or cancelled.
- GPS capability: Confirm whether the EPIRB is GPS-equipped. If not, understand the position-fix implications for your planned route.
- AIS integration: If the unit has AIS capability, confirm it is programmed with the vessel's MMSI and that the AIS output has been verified through the self-test sequence.
- Bracket mounting: Check that the bracket is positioned where it will be submerged if the vessel sinks, that the EPIRB seats correctly, and that the HRU is undamaged.
- PLBs for all crew: Confirm battery expiry dates on every PLB aboard and that each unit is registered to the correct person at beacons.amsa.gov.au.
- Hex ID record: Write the Hex ID for every beacon aboard on a card kept in a waterproof pouch accessible from the cockpit. It is the first piece of information a JRCC co-ordinator will ask for after a mayday.
Frequently Asked Questions
My EPIRB label says 'Expires 2023' - is my registration still valid?
Yes. AMSA removed the two-year renewal requirement on 4 November 2024, and all existing registrations were grandfathered at that point. Your registration is active. What you do need to do is log in to beacons.amsa.gov.au and check that your vessel details, owner phone numbers, and emergency contacts are still accurate - the old renewal cycle was the only mechanism that prompted owners to review that information, and it no longer exists.
Can I replace my EPIRB battery myself before a passage?
No. Replacing an EPIRB battery without an AMSA-recognised authorised service agent is non-compliant under AS/NZS 4280.1 and can render the beacon legally unfit for purpose. The battery enclosure must be resealed to the original waterproof specification and the unit's output re-verified - this requires tools and certification that a vessel owner does not hold. Contact an authorised agent in Cairns for current servicing timeframes and costs.
Does the AMSA registration stop working when I cross into PNG or Indonesian waters?
No. Cospas-Sarsat is a global system, and AMSA's Perth Mission Control Centre handles alerts from Australian-registered beacons wherever they activate in the world. You do not need to re-register before an international passage. What you should confirm before departing is that all emergency contacts are reachable from abroad and that your registration details accurately describe the vessel and its current ownership.
Do the PLBs each crew member carries count as the vessel EPIRB?
No. PLBs are registered to individuals, transmit for only 24 hours rather than 48, and are not required to be float-free or bracket-mounted. They cannot substitute for a vessel 406 MHz EPIRB under Australian regulations, and Queensland Maritime Safety Authority requires a vessel EPIRB regardless of vessel length for Category 1 offshore waters passages from Cairns. Carry both - PLBs protect individuals in the water, the vessel EPIRB protects the crew as a whole.
What do I do if my EPIRB goes off accidentally at the marina?
Call AMSA's National Distress Alerting System on 1800 641 792 immediately, provide the beacon's Hex ID, your vessel name, and your position, and confirm no distress exists. Stand by on VHF Channel 16. Failing to report a false activation is an offence under Australian law, and SAR recovery costs can be billed to the responsible party - the current penalty figures are available from AMSA directly. The call is straightforward and takes under five minutes.
How do I tell if my EPIRB includes GPS?
Check the label on the beacon housing - GPS models will state 'GPS' or 'with GPS' on the certification label, and the specification section of the user manual will confirm it. If the unit was purchased more than ten years ago and you cannot confirm GPS capability from the label or documentation, discuss the implications with a Cairns marine electronics supplier before committing to a remote offshore route. The position-fix difference between GPS and non-GPS models is significant enough to factor into passage planning for Torres Strait and the outer Coral Sea.