A Personal Flotation Device (PFD), also known as life preserver or life jacket, is required for every person aboard a recreational boat of any type, including canoes, kayaks, and personal watercraft. A person on water skis or knee board is considered on board the towing boat. Children under age 13 must wear their PFDs, except when below decks or in an enclosed cabin.
There are five types of PFD, types I through IV are most commonly used by recreational boaters. The lower the number the better they perform.
Type I is an offshore jacket for remote waters where rescue will probably be delayed. This device will turn most users face up. Type II is a near shore vest for protected waters where rescue is more likely to happen quickly. It will turn some users face up. Type III is a flotation aid also for inland and near shore. Users must turn themselves face up.
Type IV is a throwable device for a person in the water to hold onto while waiting rescue. Type V is special use and not normally used by recreational boaters.
Every US Coast Guard approved PFD is stamped with a label noting the PFD Type and recommended weight of user.