Safety at sea
Safety at sea: how to ensure you are found when things go wrong
Everyone on board has life jackets, that's the easy part. The question that is asked far less often is: if things go wrong tonight, how does anyone know where you are? Safety at sea ultimately revolves around that one chain: raising the alarm, being seen, and being found.
In this guide, we walk through that chain step by step. What does a marine radio do, where does its range end and a distress beacon take over, when do you need an EPIRB and when a PLB, and what is mandatory in the Netherlands? We use ACR equipment as an example because we carry that brand and know the models well. The logic behind it applies to any brand.
Safety at sea does not start with technology
Most incidents we hear back about start small. An engine that cuts out at an unfortunate moment, a sail that gets stuck, someone slipping on a wet deck. What happens next depends on preparation: did the rest of the crew know what to do, were the right items in the right place, and was there a way to reach for help.
Technology is therefore the final layer, not the first. But it is the layer that makes the difference once you can no longer do anything yourself. That is why it is useful to view your safety equipment as four steps that reinforce each other.
- Step 1, raising the alarm: marine radio with DSC. One press of the red button sends your position and MMSI to the Coast Guard and to all ships in the vicinity. The Dutch Coast Guard monitors channel 16 and DSC channel 70 continuously and can also be reached via 0900-0111.
- Step 2, raising the alarm when step 1 is no longer possible: a 406 MHz distress beacon. No range, no power, no time, or you are already in the raft. An EPIRB or PLB works via satellite and operates worldwide.
- Step 3, becoming visible to nearby ships: a SART or a beacon with AIS puts you back on the screen of any ship searching in the area.
- Step 4, being seen in the final hundred meters: life jacket lights, strobes, and emergency signals. The satellite brings a helicopter close by, then someone has to find you with the naked eye.
Safety equipment on board at a glance
These tools do not replace each other; they support each other. The further you get from shore, the more layers you need.
| Tool | Purpose | Range | View |
|---|---|---|---|
| Marine radio with DSC | First choice for raising the alarm and staying in contact with the Coast Guard | Coast Guard and ships within VHF range | VHF and AIS |
| EPIRB | Ship's distress beacon, releases automatically upon sinking in Cat I | Worldwide via Cospas-Sarsat, minimum 48 hours | Distress beacons |
| PLB | Personal distress beacon on your life jacket, also for man-overboard | Worldwide via Cospas-Sarsat, 24 to 28 hours | Distress beacons |
| SART (radar or AIS) | Makes a life raft visible to searching ships | Local, approximately 5 nautical miles | SART transponders |
| Survival radio | GMDSS radio for in the life raft, sealed emergency battery | Ships and coastal stations within VHF range | GMDSS radios |
| Life jacket light and signal | Being seen in the final hundred meters, including in the dark | Visual range, up to several kilometers | Safety lighting |
EPIRB or PLB: what is the real difference?
Technically, they do the same thing. Upon activation, a digital mayday with your position is sent via the Cospas-Sarsat satellite network to the nearest rescue coordination center. The difference lies in where the beacon is located at the moment you need it.
- An EPIRB belongs to the ship. It is kept in a bracket or housing on deck, is registered to your MMSI, and transmits for at least 48 hours. A Category I model releases automatically if the vessel sinks.
- A PLB belongs to the person. It stays on your life jacket or in your pocket, weighs a few hundred grams, and must be activated manually. Transmission time is typically 24 to 28 hours.
- The painful reality: an EPIRB still attached to a sailing ship won't help someone who has gone overboard. And a PLB in a jacket pocket in the cabin won't help anyone.
For coastal and inland sailing, a PLB per person is often the most sensible start. If you are crossing oceans or sailing further from the coast, an EPIRB is the foundation, preferably supplemented by a PLB per person. Two independent sources of alarm also give the Coast Guard confirmation that it is not a false alarm.
What to look for in an EPIRB
For ACR, there are currently two models, and the difference between them shows clearly what matters for every brand.
The GlobalFix V5 AIS transmits an AIS distress alert alongside the satellite signal. Ships within VHF range will see you immediately as a target on their plotter while the satellite route is being processed. This is a huge advantage in busy areas like the North Sea, where the first ship is often on-scene faster than a helicopter.
The GlobalFix V6 does not have AIS, but it does feature Return Link Service and NFC. Return Link Service means a blue light on the beacon illuminates as soon as your distress message has actually been received and your position is known. In a raft, with no other communication, that light is the only thing telling you that help is on the way. With NFC, you hold your phone against the beacon to read the battery status and when the last self-test was performed.
Furthermore, the same points apply to every EPIRB: at least 48 hours of transmission time, a 121.5 MHz homing signal for the final kilometers, a white and infrared strobe light for helicopters with night vision, and a battery that must be replaced after about ten years or after activation.
Category I or Category II, what do you need?
The difference lies solely in how the beacon is released from its holder.
- Category I is stored in a hydrostatic housing that releases automatically between 1.5 and 4 meters of depth. The beacon floats up, gets wet, and begins transmitting without any human intervention.
- Category II is removed from the bracket by hand. It is more compact and affordable, perfect for coastal sailing, but requires someone to be able to reach it.
- Pay attention to the mounting location. A Cat I housing must be able to float up freely. It won't work under a bimini or behind rigging.
- The release mechanism has its own expiration date. You must replace a hydrostatic release every two years, independent of the beacon's battery expiration date.
PLBs: small, but only if you wear them
A PLB is the cheapest way to bridge the gap between "the ship is still sailing" and "I am in the water." The ResQLink 400 weighs 144 grams and floats. The View models have a small display that shows your own GPS coordinates, useful if you still have phone or radio contact and want to relay your position. The RLS versions confirm, just like the V6, that your call has arrived.
No subscription, no monthly fees, no operator certificate. The battery lasts about five years. The only real pitfall is leaving the device in a drawer at home or at the bottom of a grab bag. Clip it to your life jacket and leave it there.
What you need to arrange in the Netherlands
This is the part where most confusion lies, so keep it short and clear. The National Inspectorate for Digital Infrastructure (RDI) mandates that you register both an EPIRB and a PLB.
- EPIRB: register with the RDI, after which you receive an MMSI number that is programmed into the beacon. Your supplier will do this for you. The beacon will be added to your radio license.
- Operator certificate: using an EPIRB requires at least a Marcom-B certificate. No certificate is required for a PLB.
- PLB: also register with the RDI, using your personal identification code and contact information. This information is passed on to the Coast Guard.
- No subscription: Cospas-Sarsat is funded by governments. There are no monthly or annual fees for the satellite system.
- False alarm? Call the Coast Guard Center immediately. It saves a search operation and a lot of money.
- Disposing of an old beacon? Not in the scrap metal bin. Return it to your supplier, who will ensure proper decommissioning.
Registration is not a formality. Without registration, the Coast Guard only knows that a beacon is going off somewhere; they do not know who you are, what kind of vessel you are sailing, or who they can call at home to check if you are even out at sea.
Visible to searching ships: SART and AIS
A rubber life raft gives almost no radar echo. In even slight waves, a searching ship can pass right by it, even if they know you are in that grid.
A radar SART solves this by actively responding to X-band radar. The unmistakable pattern of twelve blips in a line appears on the ship's screen, which changes into circles upon approach. The Pathfinder PRO stays in standby for 96 hours and works even if everything else has failed.
An AIS SART works the other way around and transmits positions itself, about eight messages per minute, visible on any AIS screen within approximately five nautical miles and at shore stations. For pleasure craft, this is often more practical because almost everyone has AIS on board, and not everyone uses radar during a search operation. Under GMDSS, a SART is mandatory for commercial vessels and for any vessel with more than one life raft.
The grab bag: survival radio and the rest
A standard handheld radio is fine on deck, but not built for a raft. A GMDSS survival radio has a sealed primary lithium battery that can lie idle for years and still be full, starts up immediately on channel 16 when activated, and can be operated while wearing survival suit gloves. The ACR SR303 also features NFC, so you can check the battery expiration date with your phone instead of relying on a sticker that has become unreadable.
Other items that belong in a grab bag, regardless of brand: your PLB (or on your vest), a waterproof flashlight, water, your documents, medicines, a backup phone in a waterproof case, and an emergency signal. A floating emergency bag is not a luxury, because a bag that sinks as you grab for it is just gone.
Being seen in the final hundred meters
This part is skipped most often and is the cheapest to get in order. A head in the water at night is virtually invisible without a light, even from ten meters away.
- Life jacket light: an automatic light that turns on by itself in fresh and salt water, such as the ACR HemiLight 3. Fits on almost any vest and costs a fraction of the vest itself.
- Strobe: the Firefly PRO flashes for over 56 hours and is visible for over 4.8 kilometers. The Waterbug version activates itself upon contact with water.
- Marker light for the lifebuoy: the SM-3 turns on automatically and floats upright, ensuring the buoy remains findable at night.
- Electronic emergency signal: the ResQFlare Pro signals SOS for at least three hours in red-orange and infrared. A pyrotechnic flare burns for about thirty seconds, expires, and must be disposed of like small fireworks.
- Whistle: a simple floating emergency whistle on your vest travels further than shouting and doesn't tire you out.
Searchlights: the difference between searching and seeing
In a man-overboard situation, when entering a harbor in the dark, or when relocating a buoy, a controllable searchlight is indispensable. Pay attention to candela, the light intensity in the focused beam, and not to lumens.
The ACR RCL series ranges from the RCL-50 LED with over 100,000 candela for smaller and medium-sized ships to the RCL-95 with 440,000 candela and the HID models RCL-300A and RCL-600A for professional long-range work. The RCL-85 is the easiest to install because all controls are wireless and only a power cable needs to run to the light. The XRCiZ feature moves the mechanism automatically every thirty days, preventing the light from seizing up due to salt and inactivity.
Maintenance: what expires when
Safety equipment is the only thing on board that you buy hoping never to use, and for that exact reason, everyone forgets about it. This is the schedule we follow.
- Monthly: self-test of EPIRB and SART, according to the manufacturer's instructions. For beacons with NFC, read the test result with your phone.
- Every two years: replace the hydrostatic release for a Cat I setup.
- Approximately five years: PLB battery.
- Approximately ten years: EPIRB battery, or sooner if the beacon has been activated. Replacement is performed by an authorized dealer or battery service center, which then re-tests the beacon.
- Annually, start of the season: test life jacket lights, check batteries in strobes, open the grab bag and check the contents.
- Upon sale or relocation: update registration with the RDI. Outdated contact details waste time in a real-life situation.
Checklist per sailing area
- Inland and sheltered waters: DSC VHF radio, life jackets with automatic life jacket lights, whistle, and a PLB for those sailing solo.
- Coastal and Wadden Sea: the above plus one PLB per person on board, an electronic emergency signal, and AIS on board.
- Crossings and offshore sailing: EPIRB (Cat I if it is possible that no one can reach it in an emergency), one PLB per person on board, grab bag with survival VHF, SART, strobe lights, and spare batteries.
- Commercial shipping under GMDSS: EPIRB, SART, and survival VHF according to the requirements for your sailing area, with valid inspections and certification (SOLAS, MED).
Mini glossary
- EPIRB: Emergency Position Indicating Radio Beacon. 406 MHz emergency beacon associated with the vessel and registered to the MMSI.
- PLB: Personal Locator Beacon. Personal 406 MHz emergency beacon that you carry on your person.
- Cospas-Sarsat: the international, government-funded satellite system that detects 406 MHz emergency signals and forwards them to the nearest rescue center.
- RLS: Return Link Service. Confirmation via Galileo, visible as a light on the beacon, that your emergency message has been received.
- SART: Search and Rescue Transponder. Makes a life raft visible on radar or AIS.
- HRU: Hydrostatic Release Unit. The release mechanism that deploys a Cat I beacon when sinking, to be replaced every two years.
- GMDSS: Global Maritime Distress and Safety System, the international system for maritime distress and safety communication.
Our honest advice
Start with what you actually wear. A PLB on the life jacket of every person on board provides more safety than a more expensive beacon sitting in a cupboard. If you sail beyond the coast, an EPIRB is the foundation and you should choose Cat I as soon as the scenario is conceivable that no one can reach it anymore.
And don't forget the cheapest part. Life jacket lights, a whistle, and an electronic emergency signal together cost less than one beacon, but they determine whether you are seen in the last hundred meters.
Frequently asked questions about safety at sea
What is the difference between an EPIRB and a PLB?
An EPIRB belongs to the ship, is registered to the MMSI, and transmits for at least 48 hours. A Cat I EPIRB is automatically released when sinking. A PLB is worn by yourself, activated manually, and typically transmits for 24 to 28 hours. Both use 406 MHz via Cospas-Sarsat.
Do I need to register my emergency beacon in the Netherlands?
Yes, both an EPIRB and a PLB must be registered with the RDI. With an EPIRB, you receive an MMSI number that is programmed into the beacon. Without registration, rescue services do not know who is sounding the alarm.
Do I need a certificate for an emergency beacon?
A Marcom-B certificate is the minimum requirement for using an EPIRB. In the Netherlands, no operator certificate is required for a PLB.
Are there subscription fees for a 406 MHz emergency beacon?
No. The Cospas-Sarsat system is publicly funded. You pay for the beacon, registration is handled via the RDI, and there are no other subscription fees.
Is an AIS beacon an alternative to an EPIRB?
Not as a replacement. AIS works locally and is only visible to ships with AIS within about five nautical miles. That is fast and useful in busy areas, but it does not alert rescue services if no one is in the vicinity. Satellite and AIS complement each other, which is why some beacons do both.
How often should I test my EPIRB?
Perform the self-test monthly according to the manual. If it passes, the beacon is working. Additionally, have the battery replaced on time and check the expiry date of the hydrostatic release unit for a Cat I setup.
What should I take with me if I have to abandon ship?
Stay with the ship as long as possible, as it is easier to find than a person. If you must leave, take the grab bag, the survival VHF, and your PLB (or wear it already) and ensure the EPIRB goes with you or is left activated.
Are you unsure about what you need on board?
You don't buy safety equipment every week, and the choices are certainly not obvious. We are happy to help you assess your sailing area, your current equipment, and what is required or advisable for your vessel. From the right category of EPIRB to registration, programming, and the location on board where the beacon can actually float free.
Official dealer, fast delivery, and advice from people who sail themselves.
