In this session, you’ll learn about buoyancy — the tendency of a body to float or sink in water or any fluid. You’ll learn how a life jacket with just fifteen-to-sixteen pounds of buoyancy generally can provide adequate flotation for an adult. You’ll also learn which body types are the most difficult to keep afloat. And you’ll learn the three basic kinds of life jacket flotation used for U.S. Coast Guard approved life jackets. Plus how to ensure that your life jackets are in serviceable condition. What problems are we trying to avoid? Not understanding that people will naturally float in water. Most people require only about fifteen-to-sixteen pounds of extra buoyancy to keep their heads out of water. Failing to realize that the people hardest to float are those with compact, dense bodies. A person with higher body fat may actually have an easier time floating. And even for a person with large muscle mass, a life jacket with twenty-two to thirty-four pounds can provide superior performance. Not understanding the implications of different amounts of flotation among various life jacket types. So, how do we do it right? Life jackets basically displace enough water to make the persons wearing them more buoyant. Most people require only about fifteen-to-sixteen pounds of extra buoyancy to keep their heads out of water. People with athletic body builds, who have a lot of bone and muscle mass and not much fat, may need added buoyancy. Understand basic kinds of life jacket flotation for U.S. Coast Guard approved wearable life jackets. Inherently buoyant primarily foam life jackets, with recent vest-style designs making them much more comfortable than older style life jackets. Inflatable – the most compact – which to meet carriage requirements can be worn only by persons over sixteen years of age and need care to ensure they are serviceable. And life jacket types, which meet buoyancy requirements with their inherent foam material and add inflation for extra buoyancy — also quite comfortable in recent designs. Inherently buoyant life jackets should be checked for rips, tears, or open seams in fabric or coatings large enough to allow the loss of buoyant material. Life jackets with buoyant material that has become hardened, non-resilient, permanently compressed, waterlogged, oil-soaked, or which show evidence of fungus or mildew, or not securely held in position, should be replaced. Inflatable life jackets must be equipped with a properly armed inflation mechanism, complete with a full inflation cartridge, and all status indicators showing that the inflation mechanism is properly armed. Inflatable chambers should be checked to ensure they are capable of holding air oral inflation tubes not blocked, detached, or broken; and manual inflation lanyards or levers all accessible; and inflator status indicators functional. Remember, the law says that life jackets must be in good shape before an operator uses his or her boat. Ones that are not in good shape should be cut up and thrown away.