Life Jacket or Buoyancy Aid?

This is a rough guide only and is no substitute for taking a recognised boat handling course or – a chat with the RNLI.

The difference between a buoyancy aid and a life jacket

  • Only a life jacket will keep the wearers head above water.
  • If you fall in face down it is designed to turn you over.
  • A buoyancy aid will not prevent you from drowning.
  • If unconscious or disabled and the wearer is unlucky to be face down, a buoyancy aid will not turn you over.

Buoyancy aids are only recommend for water sports where you doing things like water skiing, mono boarding, being towed in an inflatable toy and there are at least 2 people in the boat i.e. someone steering and someone looking at the person being towed.

Other uses may include canoeing, kayaks etc.

If you are in any doubt please contact the RNLI on 0300 300 9909

Life Jackets:  The 3 Main Types

None Automatic:         Foam based – tend to be rather bulky and restrict movement

Semi automatic:          You need to pull a cord for them to inflate

Fully Automatic:          These auto inflate when you fall in

Each main type above has its pro’s and cons and prices range from £15.00 to anything upwards of £200.00+ depending on requirements.

None Automatic / Foam Life Jackets

These are by far the most reliable jackets on the market as they cannot deflate or be set off by mistake.  The downside is that they tend to be bulky and can restrict movement so are great for children but not perfect for active sailors.

Semi Automatic Life Jackets

These are cheaper than then fully automatic life jackets and a lot less bulky than the foam based jackets, however they do need to be well maintained with the gas cylinders being replaced as per the manufactures recommendations which is normally every 1-3 years.

Note that due to the need to pull a cord to inflate this type of lifejacket , they should only be warn when there is no chance of injury when the person falls in.

Fully Automatic life jackets

These auto-inflate when you hit the water and for many boat users are seen as the best type to buy as no manual intervention is needed.  Please remember that like the semi-automatic life jackets that you will need to replace the gas cartridge every few years.

Buoyancy Ratings

Children up to 9 years old normally would use a life jacket of 100N and adults should be rated to 150N where they are being used for pleasure activities i.e. lochs, lakes and coastal waters where the user will not be in the water for a prolonged length of time.

Lifejackets that are at 270N tend to be used by deep sea fishermen, long distance sailors etc.


It is vital to make sure that your lifejacket fits properly and will not rise above your head. To stop this happening some jackets have inbuilt harness and most can be bought with a crotch/ leg strap but this can often be an optional extra.

If you are unsure about this key point in buying a lifejacket please seek professional advice and try the jacket on before purchase.

Other things to consider

Hoods: these are often optional extras that are designed to minimise heat loss for users who might not be rescued quickly.

Comfort: This might sound obvious but some jackets fit some people better than others and cheap lifejackets tend to be less comfortable than the more expensive models so again it is worth while trying a few on before you make your purchase.

Lights: There are various different types of lights that can be bought as an added option and range from automatic i.e. they turn on when you hit the water including in daylight and type of light i.e. constant, strobe etc.

Buoyancy Aids

As with life jackets you need to make sure that you are buying the right one for job and hence you should consider:

Buoyancy rating

Comfort and Fit (see above)

In most cases this is made easier due to buoyancy aids being designed for a specific function i.e. kayaking, water skiing etc. and will come with a range of options from pockets to hydration bladders.

Obviously  someone out canoeing all day might want pockets for food and a hydration bladder so that they can drink on the move where as a jet skier would prefer some extra protection for when they fall off at speed.


Whatever water sport you decide to do we strongly advise using the right lifejacket/ buoyancy aid for your requirements and if you are not sure what to buy please seek professional assistance.