Advice - Buoyancy

Advice - Buoyancy

Buying a Buoyancy Aid / Impact Vest or Life Jacket

The first thing to understand about a Buoyancy Aid is that it is fundamentally different in design and in purpose to a Life Jacket and to an Impact Vest.

Buoyancy Aids

A Buoyancy Aid is simply designed to make life easier if you are taking part in a water sport that involves you actually (or potentially) being in the water at some point. Buoyancy Aids will assist your flotation greatly, but generally speaking you still need to be able to swim in order to stay fully afloat with your head above the water. A Good Buoyancy Aid will provide a certain amount of insulation on cold days and most will provide varying amounts of impact protection depending on their design and the materials used.

The accepted standard for a Buoyancy Aid is that is provides 50N of floatation and that it is ISO-approved. Buoyancy Aids are worn like a jacket and fasten at the front or side with either snap buckles or zips (or both). As with most things, you get what you pay for and we recommend that you should always spend as much as you can comfortably afford as the more expensive models are generally made from higher quality and harder wearing materials, are more comfortable, and have more adjustments / features for the perfect fit.

Impact Vests

An Impact Vest differs from a Buoyancy Aid in that it is designed primarily for protection and freedom of movement rather than buoyancy. They may, however, offer up to 50N of buoyancy in some cases but they rarely meet the necessary ISO standards required of a buoyancy aid as their main purpose is different.

Impact Vests are intended for use during high-speed watersports where potential injury could occur from coming into contact with the water (or obstacles / equipment) at high speed. Impact vests are intentionally made to be tight fitting so that they stay put during a hard fall and as a result they can take a bit of getting used to at first.

Many designs offer a front zip, which makes entry and exit much easier, but some are literally pull-over style and are pulled over the head rather than zipped or buckled up. Although a little more awkward, pull-over vests offer the ultimate in mobility, especially when tucking forward, as there is no rigid zip to get in the way.

Impact vests tend to be thinner than buoyancy aids as this improves mobility. They often have segmented panels, which are separate sections (often visible) that allow the vest to flex more at the joints. Some also have added protection in critical areas of the torso and spine such as around the ribs (handy when riding at the cable park).

Life Jackets

A Life Jacket differs from a Buoyancy Aid in that it is designed primarily to keep you afloat, even if you can't swim, and to rotate you onto your back if you are unconscious so that your head is held above water and you can breathe. For this reason, Life Jackets tend to be bulky and have a pronounced head / neck support plus straps to ensure that the jacket does not come off if the user is thrown into the water at speed. Wearing a Life Jacket for most recreational water sports is impractical and uncomfortable, but using them for boating or perhaps kayaking would be perfect, and if you want to tow younger kids in towable inflatables then we also recommend Life Jackets for this purpose too.

Which is Right For Me?

For most recreational water sports activities a well fitting buoyancy aid will be exactly the right thing to wear. However, if you are a competent wakeboarder or skier and you like to shred hard then we recommend that you wear an impact vest.

The interior of a buoyancy aid will be soft foam and the exterior cover will be either nylon or neoprene. Nylon is generally cheaper and harder wearing than neoprene and it dries quicker, but neoprene is much softer and more comfortable against the skin, especially when you are not wearing a wetsuit. It also provides better thermal insulation. If you can justify the extra cost then always go for neoprene, but having said that nylon is perfectly good for most applications. 


Correct fit is everything when it comes to buoyancy aids and spending time in the wrong one will not only spoil your day but it could also be dangerous. To check that you are wearing the correct buoyancy aid for your height and weight just perform these simple tests (always perform these checks with the vest fully fastened).

1 - Is it comfortable? If it is rubbing or is too tight somewhere then it could be a simple matter of relaxing one or more of the adjustment straps. If after doing this you still feel uncomfortable then go for the next size up.

2 - Try taking a few nice deep breaths. If the jacket restricts your breathing at the top of each breath then relax the adjustment straps. If after doing this you still feel uncomfortable then go for the next size up. Remember that some watersports can make you quite out of breath and being able to breathe properly is obviously important.

3. Lift your arms up above your head. If the Buoyancy Aid does not move above the level of your ears then it is the correct size. If the jacket ends up over your head then it could be a simple matter of tightening one or more of the adjustment straps. Start tightening the straps at the waist and work your way up. If the vest has shoulder straps, tighten them last. Repeat the test and if the jacket still ends up over your head then it is too big so go for the next size down.

4. Ask someone pull up on the shoulders. If it moves up past the level of your ears then try tightening the straps. Repeat the test and if it still moves up above your ears then it is too large so go for the next size down.

Good Practises

  • Don't use your Buoyancy Aid as a cushion. It will damage the foam and it will lose buoyancy.
  • Don't leave your Buoyancy Aid lying in direct sunlight for long periods.
  • Always rinse your Buoyancy Aid in fresh water after use, especially after being in salt water.
  • Drip-dry your Buoyancy Aid before storing. Store in a cool, dry, dark place where there is good ventilation.

How Much Buoyancy Do I Need?

Buoyancy is measured in Newtons (N). 

  • Level 50 Buoyancy Aid: Not recommended for weak or non-swimmers. No self-turning ability.
  • Level 70 Buoyancy Aid: Equivalent to the old system’s Type III PFDs. They are the most common PFDs worn by recreational boaters. No self-turning ability.
  • Level 100 Life Jacket: High flotation PFD. Some self-turning ability.
  • Level 150: High flotation PFD. Offshore waters, self-turning ability.

Combined British and European Standards (BS ENs) exist for buoyancy equipment. Each Standard is intended to be suitable for different activities in various risk situations.

BS EN 393:1994 Buoyancy aids: 50 N. These have a buoyancy of no less than 50 Newtons for the average adult and are intended for use in sheltered waters when help is close at hand and the user is a swimmer, and in circumstances where more bulky or buoyant devices would impair the user’s activity or actually endanger them.

BS EN 395:1994  Lifejackets: 100 N. These have a buoyancy of no less than 100 Newtons for the average adult and are intended for relatively sheltered waters when normal clothing is being worn and the wearers remain capable of helping themselves.

BS EN 396:1994  Lifejackets: 150 N. These have a buoyancy of no less than 150 Newtons for the average adult and are intended for use in tidal waters or when foul weather clothing is being used; and where the wearers may not be capable of helping themselves due to injury or exhaustion (or where there may be a delay in rescue).