An introduction to Newtons

The body does not weigh as much in water as it does on dry land.

50 Newtons (usually expressed as 50N) is normally enough to maintain an adult’s buoyancy.  

N = the unit of buoyancy. 1 kg = 9.81 N (which, for readers in the US, equates to approx 11.25 lbs

Regatta’s products are CE marked, which certifies conformity to European Standards.




The main levels of buoyancy are:

50N – EN 393
Life vests, flotation jackets & flotation suits. For use
by swimmers in protected waters where help is nearby. Not a lifejacket!


100N – EN 395
High fluorescent flotation garment with reflective strips, which - under strict test conditions - must be able to turn the wearer onto their back. People who cannot swim should always wear a lifejacket. For use in protected waters.


150N – EN 396
Lifejackets. For use in coastal and offshore waters, with foul weather clothing. Level of buoyancy should be carefully checked in cases where heavy tools or equipment are being used by the wearer.



275N – EN 399
Inflatable lifejackets. Offshore, shipping and industry for extreme conditions. Can be used with strong protective clothing, most survival suits and safety harnesses.

The Thermo Cruise Baby provides 100 Newtons of buoyancy.

Measuring Buoyancy