In short: Choose a life jacket for the water you sail in, what you wear and who will wear it.
- 150 N is the usual choice for adults on coastal and open water. It is designed to turn an unconscious person in normal clothing onto their back.
- 275 N is for offshore sailing, heavy weather and heavy clothing. A 50 N jacket is a buoyancy aid, and it will not turn you over.
- An inflatable is easy to wear all day but needs checking every year. A foam jacket floats without a gas cylinder or firing mechanism and needs almost no maintenance.
- For children, we recommend a foam jacket with a collar and crotch strap in the right weight class.
For most adults sailing in Danish and Baltic waters, an automatic inflatable 150 N life jacket with a crotch strap is the right starting point. Choose 275 N for offshore passages and heavy clothing, and foam jackets for children. A life jacket only helps if it suits the situation and you are wearing it. All types are in our life jacket range.
We recommend a properly sized jacket for everyone on board, guests and children included. In Danish waters, Søfartsstyrelsen's order on life jackets in small vessels (no. 766 of 20 June 2024) requires every boat that is not moored in a harbour to carry a CE- or wheel-marked life jacket or buoyancy aid of the correct size for each person on board, and the skipper is responsible. Rules can change, so check the current text with Søfartsstyrelsen, the Danish Maritime Authority, and with the authorities at home if the boat is registered abroad.
What is the difference between a buoyancy aid and a life jacket?
A life jacket is built to turn you onto your back and keep your mouth clear of the water, even if you are unconscious. A buoyancy aid only adds buoyancy, so you must be able to swim and keep your own head up.
Buoyancy aids are typically 50 N and are used for dinghies, kayaks and water-skiing close to shore, where help is near. They will not keep the face of an exhausted, cold-shocked or unconscious person clear of the water. On a boat where you could fall overboard far from land, wear a life jacket.
How many newtons does a life jacket need?
For most adults on a leisure boat, 150 N is the natural starting point. Buoyancy is measured in newtons (N), and the standard EN ISO 12402 divides jackets into four classes. The class is on the jacket's label.
| Class | For whom and where | Turns an unconscious person? |
|---|---|---|
| 50 N (EN ISO 12402-5) | Buoyancy aid for swimmers close to shore, with help nearby | No |
| 100 N (EN ISO 12402-4) | Sheltered water and calm weather, where quick help can be expected | Not reliably, especially in heavy clothing |
| 150 N (EN ISO 12402-3) | Coastal and open water: the usual choice for leisure sailing | Yes, in normal clothing |
| 275 N (EN ISO 12402-2) | Offshore, heavy weather, heavy clothing or tools and equipment worn on the body | Yes, also in heavy clothing |
Rule of thumb: if you sail far from land, in heavy weather or in thick foul-weather gear, choose 275 N. Clothing that traps air can stop a jacket turning you onto your back, and 275 N is designed for exactly that. Always follow the manufacturer's guidance on weight and use.
Many inflatables are marked 165 N or 180 N. That is the jacket's actual buoyancy; the class is usually 150 N (EN ISO 12402-3).
Which life jacket for which kind of sailing in Danish waters?
Match the class to how far you are from help and how rough it can get. These are rules of thumb; the manufacturer's guidance comes first.
| Sailing | Rule-of-thumb choice |
|---|---|
| Dinghy, kayak or paddleboard close to shore in summer, with help nearby | 50 N buoyancy aid |
| Day sailing in sheltered water, such as the South Funen Archipelago or the Limfjord, in calm weather | 150 N; 100 N foam only with help close by |
| Coastal cruising and crossings in the Kattegat, the Belts or the western Baltic | 150 N with harness |
| Sailing at night, alone, or early and late in the season | 150 N with harness and a light; 275 N in heavy clothing |
| Offshore passages, such as across the North Sea or the open Baltic | 275 N with harness and sprayhood |
Foam or inflatable life jacket?
Rule of thumb: the jacket that helps you is the one you actually wear.
- A foam jacket floats immediately and only needs checking for wear and damage. It is bulky and warm to wear, and adult foam jackets are often 100 N. It suits children, guests and short trips in calm weather.
- An inflatable jacket is comfortable all day, also when you work on deck. Inflated, it typically gives 150 N or more. It must be checked at least once a year, and it only works if the cylinder and firing mechanism are in order.
Many sailors choose an inflatable for themselves and foam for children and guests. See our inflatable life jackets, with and without harness.
Automatic or manual inflation: which should you choose?
Choose automatic unless you have a specific reason not to. An automatic jacket inflates by itself in the water, even if you are knocked unconscious or in shock. A manual jacket only inflates when you pull the handle.
The first minute in cold water is the reason. Cold-water researcher Gordon Giesbrecht's widely taught 1-10-1 principle describes about one minute of cold shock with gasping, about ten minutes of useful movement, and up to about an hour before hypothermia leads to unconsciousness. Early and late in the Danish season the sea is cold, and in that first minute you may not manage to pull a handle.
- Water-sensitive firing: a tablet or bobbin dissolves when wet and fires the cylinder. It can also fire in a puddle or after long, heavy spray.
- Hydrostatic firing: reacts to water pressure once the firing head is a short way below the surface. Rain and spray do not set it off, so it suits sailing with lots of water over the deck.
All inflatables can also be fired by hand and topped up by mouth. A manual jacket can be a deliberate choice in an enclosed wheelhouse, where a jacket inflating inside a capsized boat can make escape difficult; you must then remember to pull the handle.
Do you need a life jacket with a harness?
Yes, if you sail a yacht, sail at night or in heavy weather, or sail alone. A built-in harness lets you clip on with a tether, and staying on board is far safer than being recovered from the water. Check that the harness is approved to EN ISO 12401.
- Clip on before you come up the companionway, and unclip only when you are below again.
- Clip on to a strong eye or a jackstay, never to the guardwires.
- Use a short tether where you can. A double tether lets you stay clipped on while you move.
Separate tethers and harnesses are under tethers and safety harnesses.
How should a life jacket fit?
Snugly. A loose jacket can ride up over your head in the water.
- Choose the size by weight and chest measurement; both are on the label. Adult inflatables are often for people from about 40 kg, but check the maker's figure.
- Tighten the waist belt. Rule of thumb: there should be just room for a flat hand between belt and body.
- Use the crotch strap or thigh straps. Without them an inflated jacket can be pushed up around your ears.
- Test the fit: ask someone to lift the jacket by the shoulders. If it slides up to your chin, it is too loose.
Try the jacket on over the clothes you sail in.
Which life jacket should children wear?
We recommend a foam jacket with a large collar and a crotch strap for children. The collar supports the head, the crotch strap stops the child slipping out, and a grab handle at the neck helps you lift the child back aboard.
- Choose by the child's weight, not age. Children's jackets come in weight classes, such as 15–30 kg, shown on the label.
- Do not buy a jacket for the child to grow into. One that is too big can slide up over the head.
- Use an inflatable on a child only if the manufacturer has explicitly approved it for the child's weight.
- Try the jacket in the water before the season, in a pool or shallow water with an adult alongside.
See our children's life jackets.
Frequently asked questions
Does everyone on board need a life jacket in Denmark?
We strongly recommend one properly sized jacket per person, preferably worn. In Danish waters an approved jacket of the right size for every person is required whenever the boat is not moored in a harbour (order no. 766 of 2024); check the current text with Søfartsstyrelsen.
Is 150 N enough in Danish waters?
For most adults in ordinary sailing clothes on coastal and open water, yes. Far from land, in heavy weather or in heavy clothing, choose 275 N.
How often should an inflatable life jacket be serviced?
At least once a year before the season, every time it has inflated, and at the manufacturer's service interval. How to service an inflatable life jacket takes you through it step by step.
How long does a life jacket last?
It depends on type, use and storage. Replace a foam jacket if the foam is compressed, hard or cracked, or the fabric is weak. An inflatable can last many years if it is checked. Follow the manufacturer's guidance on service life.
Any questions?
Not sure about size, buoyancy or firing mechanism? Write to us via the contact page with your weight, your boat and where you sail, and we will help you find a jacket that fits.
