How to choose the right lifejacket?

Lifejacket, PFD (Personal Floatation Device), buoyancy aid, life vest.. whatever you call them they are all designed for one main purpose which is to aid your floatation. 

  • Drivers wear a seatbelt, 
  • Motorcyclists wear a helmets, 
  • Skydivers wear a parachute, 
  • Boaters wear a lifejacket.. 

Understanding the buoyancy of a PFD, lifejacket or buoyancy aid:

A Newton is a measurement in relation to a buoyancy aid / lifejacket this is how much weight it can support. 


150 Newton or above Lifejacket: Use on coastal or Offshore waters. It is designed to turn an unconscious casualty onto their back and keep their face out of the water. 

275 Newton Lifejacket: Use on Offshore waters. Functions the same way as a 150N but has a higher Newton value to cater for the wearer having heavier clothing / equipment. 

Buoyancy Aids:

50 Newton or above Buoyancy Aid: Generally known as a 'buoyancy aid' to be used in more sheltered conditions where you are 'in company' if assistance was required. Used by those doing watersports such as dinghy sailing, kayaking, waterskiing, jet skiing etc 

100 Newton Buoyancy Aid: Sheltered or calm waters, it is unlikely to turn you onto your back if you were unconscious but is more supportive that a 50 Newton version.

Correct fitting:

If a lifejacket / PFD / Buoyancy Aid fits properly: 

It will help keep your head above water. If its too big it will ride up around your face, if its too small is won't keep you afloat.

  • Always try it on for size
  • Check the table to ensure its correct for your size & weight
  • Make sure it correctly fastens
  • Hold your arms above your head and get someone to tug it gently upwards to check it does not ride up over your face/chin.. 

Types of Lifejacket / Buoyancy Aids & Personal Floatation Devices:

Auto Inflation:

  • Inflates automatically upon immersion. 
  • Comfortable & cool
  • May turn unconscious wearer face up
  • Requires regular maintenance 
  • Not suitable for 'wet' watersports i.e. waterskiing, jet skiing etc. 

Manual Inflation:

  • Only Inflates manually upon immersion. 
  • Comfortable & cool
  • May turn unconscious wearer face up
  • Requires regular maintenance 
  • Not suitable for 'wet' watersports i.e. waterskiing, jet skiing etc. 

Buoyancy Aid:

  • Fixed buoyancy, great for children and people nervous around the water
  • Requires little maintenance 

Buoyancy Aid:

  • Comfortable
  • Good freedom of movement
  • Requires little maintenance 
  • Unlikely to turn unconscious wearers face up
  • Suitable for watersports i.e. kayaking, dinghy sailing, windsurfing

Impact Buoyancy Aid:

  • Designed to keep you afloat in possible immersion
  • Requires little maintenance 
  • Rugged construction 
  • Designed for high impact/speed watersports i.e. waterskiing, wake boarding, jetskiiing

Impact Vest:


  • Requires little maintenance
  • Designed for high impact / speed watersports i..e waterskiing, wake boarding
  • Little or no floatation

What type of PFD / lifejacket / buoyancy aid should I use?

A buoyancy aid has fixed integral buoyant foam, vs a lifejacket that is inflated when you need it ! 

50 N + Buoyancy aid

  • Dinghy Sailing
  • Windsurfing
  • Kayaking / Canoeing
  • Stand Up Paddle Boarding

50 N Impact Buoyancy Aid

  • Jetskiing
  • Waterskiing / Wakeboarding
  • Tow Inflatables

100 N Buoyancy Aid

  • Non-swimmers going afloat in sheltered waters

150 + Newton Manual Lifejacket

  • Powerboating / Sailing / Motorcruising in Coastal or Near Offshore Waters

150 + Newton Automatic Lifejacket

  • Powerboating / Sailing / Motorcruising in Coastal or Offshore Waters

275 Newton Automatic Lifejacket

  • Powerboating / Sailing / Motorcruising in Offshore Waters
  • Working in heavier clothing / equipment / tools

Manual vs. Automatic Gas Inflation Lifejackets:

Manual Inflation Lifejackets:

  • Inflated only by manually pulling a cord 
  • Good for use in 'wet' environments i.e. lots of water spray where you don't want it to inflate accidentally
  • Does not work unless you pull the cord, therefore if you are incapacitated it won't help you! 

Automatic Inflation Lifejackets:

  • Either water or pressure (hydrostatic) activated 
  • Water activated lifejackets are more cost effective and can be easier to maintain 
  • Both automatic systems (assuming correctly maintained) will inflate when / if you fell in the water. 

Water Pressure Activated (Hydrostatic) Automatic Inflation Lifejackets:

  • Pressure (Hydrostatic) activation is great if you get lots of water spray as it will only activate when the lifejacket is submerged in water (approx 10cm) i.e. if you fell in. 

How does a Lifejacket work?

Dependant on whether your lifejacket is manual or automatic will depend when / how it is inflated - either way they do inflate (assuming correctly maintained). When activated the CO2 cannister inflates the bladder and will rotate you so you are face up in the water. 

Lifejacket Accessories:


  • Reflective Tape - makes you easier to be seen when someone is searching with a torch or similar 
  • Whistle - means of attracting attention
  • Manual Inflation Tube
  • Manual Inflation Pull Cord

Optional Extras:

  • Crotch strap/s - stops the lifejacket riding up which helps keep your face clear of the water
  • Spray Hood - helps keep the water clear of your face/ airways 
  • Light - water activated to ensure you can be seen at night
  • Personal Locator Beacon / AIS MOB

Parts of a lifejacket:

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