Buoyancy aids are a specialist form of personal flotation device (PFD) used most commonly by kayakers, canoeists, people practicing rafting, and dinghy sailors.
The foam used is typically closed cell PVC (polyvinyl chloride), although some manufacturers are now starting to use less toxic and more recyclable materials.
Some lower quality ones only offer a belt, and these are often poor fitting and may be designed for generic water sports rather than specifically canoeing/kayaking.
Minimalistic designs which tend to hug the body tightly and are well cut around the arms aim to allow the wearer complete freedom of motion (something important to both Slalom and Polo paddlers as well as playboaters).
These vests may not be fully suitable for other purposes, such as whitewater paddling where additional buoyancy is required due to the higher flow of water.
They have to be comfortable to wear whilst paddling for long distances, and so typically have very low cut sides to allow the arms free movement.
More recently they are being designed more and more like whitewater vests, with low cut fronts to allow the paddler to lean forward easily.
As an example, WW harnesses require a significant load to release effectively, (usually provided by the force of the water, when a rescuer in the river is held by rope from the bank).
Buoyancy aids come with a set of specifications detailing their sizing, weight range, and the standards they adhere to.
Buoyancy aid and personal flotation devices need regular and routine inspection of any belts, stitching and other parts.
This wear and damage serve as valuable indicators on when to retire a personal flotation service or buoyancy aid.
Ancient instances of the life jacket can be traced back to simple blocks of wood or cork used by Norwegian seamen.