Check to see what the USCG Approved/Type rating is for the vest.

The Five Types of PFDs

Types I PFDs, or offshore lifejackets, are the most buoyant PFDs and suitable for all water conditions, including rough or isolated water where rescue may be delayed. Although bulky in comparison to Type II and III PFDs, offshore jackets will turn most unconscious individuals to the face-up position. They range in sizes from adult to child.

Type II PFDs, or near-shore buoyancy vests, are for calm and open water where a rescue will occur quickly. They are not designed for long periods in rough water. These vests will turn some, but not all, unconscious wearers face-up in the water. Some inflatable Type II models will turn wearers to the face-up position as well as a Type I PFD. This vest is less bulky than a Type I and often the least expensive of the PFD types. Type II PFDs are available in a variety of sizes.

Type III PFDs, or flotation aids, are for calm and open water where a rescue will likely occur quickly. These PFDs are designed to keep the wearer in a vertical position. It is the wearer's responsibility to maneuver themselves into a face-up position, usually accomplished by tilting their head back. Type III inflatable models will keep unconscious wearers face-up as well as a Type II inherently buoyant vest. This PFD is not recommended for rough water conditions. These PFDs are the most comfortable to wear and popular for recreation boating and fishing. Type III PFDs come in various sizes from adult to child.

Type IV PFDs, or throwable devices, are for calm conditions where rescue will happen quickly. Not designed to be worn, these PFDs are tossed to a conscious person who can hold onto it for flotation until rescued. A square buoyant cushion, a life ring, or a horseshoe buoy, are some Type IV examples.

Type V PFDs are also referred to as special use devices. These devices are to be worn for specific activities as described on the unit's label. To be effective Type V PFDs must be used in accordance with the label's specifications. Many must be worn at all times in order to qualify as a PFD. A Type V's label will also list its performance as a Type I, II, or III PFD. A Type V PFD, like a full body survival suit, provides protection from hypothermia; however, these suits are best suited for cool climates as they can become quite warm in mild or hot weather.