A personal flotation device (also named PFD, life jacket, life preserver, life vest, life saver, cork jacket, life belt) is a device designed to keep a wearer afloat and their head above water, often in swimming pools, rivers, lakes, and oceans. The term includes all types of such devices from life preservers to life jackets to survival suits. They are available in different sizes and different designs purposed for various levels of protection.

Whenever possible choose life vests instead of a buoyancy aids. They can turn unconscious people on their back, allowing them to breathe. Buoyancy aids don't. Life jackets assist deep water activities including entries and treading water.

Practice wearing a life jacket, enter the water using ladder, steps or side. Float for a few minutes in the HELP position and Huddle position. Use a life jacket to tread water and swim to safety.

Bulky, but floats you the best. Best flotation for open, rough or remote waters. Turns most unconscious wearers face-up in the water. A Type I PFD provides more buoyancy than any other type and turn most unconscious wearers into a face-up position with their head out of the water.

This type requires a minimum adult buoyancy of 10 kg. Because of its bulk it is generally not comfortable to wear when not on the water. They are typically jacket-shaped but sleeveless, and usually have multiple ties and belts for closure.

Familiar to anyone who has rented a canoe or other pleasure craft, these are the bright orange vests also seen on water taxis and the like. They are a reduced version of the type I PFD, and provide a minimum 7 kg buoyancy. They usually have one belt and one tie.

Type II PFDs are used near shore where a quick rescue is likely. They will usually turn the face of an unconscious person out of the water, but are not as dependable as Type I PFDs for this task.

Most popular with canoeists, kayakers and small-boat sailboat racers, a Type III PFD is best for conscious wearers who can keep their own faces out of the water. They will not turn you on your back, but let you float face down. Hence they are known as "Insurance Covers" because they fulfill insurance requirements, but not much else.

Type III PFDs are usually jacket-style and may have pockets, lashing hooks, tow belts, and other functions that enhance their application. They typically fit the wearer closely, and many have buckles or zips to close. The minimum buoyancy is 7 kg, but some designs have higher buoyancy (frequently 8 kg).

A common sight around leisure centres are buoyancy aids that are worn in the wrong size. They reach over the ears and are way too large. This is a hazard as it can lead to breathing difficulties.

 

Throwable PFDs are designed for areas where there is constant boat traffic and rescue is immediate. They are commonly ring-shaped, but horseshoe and cushion type IV PFDs are also made. These are only a backup measure and should generally be thrown by someone with experience, as it is difficult to aim well, especially in rougher water. A cushion-style PFD has a buoyancy of 8 kg, while a ring-style has a buoyancy of 16.5 pounds.

Under some circumstances a throw bag, containing a floating rope to extend a line to a nearby swimmer or boat, can substitute for a throw able PFD.

Approved for the activities listed on the label. Some are approved for white water rafting, board sailing, etc. This type also includes new hybrid PFDs with foam floatation and an inflatable chamber. Type V Hybrid PFDs are as comfortable to wear as a Type III but when fully inflated have the floatation performance of a Type II or better.

Their turning performance (keeping an unconscious person face-up) is rated according to PFD types I, II, and III. Type V PFDs come in a variety of styles, from full-body suits to work vests. Some have a safety harness and some provide protection against hypothermia (survival suits).