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How Life Jackets Work


Testing and Maintaining a Life Jacket
Life jacket fit can be tested in shallow water, like a swimming pool
Life jacket fit can be tested in shallow water, like a swimming pool
Photodisc/Getty Images

You've picked out which life jacket works best for you and the type of water activity you'll be doing, but you shouldn't head out for the boat just yet. Test the life jacket in shallow water to make sure that it fits. When correctly fastened, the life jacket should stay in place and not ride up. You can test the fit of a child's flotation device by picking the child up by the shoulders of the jacket.

It's also worthwhile to test a life jacket in slightly deeper water to measure the freeboard. Freeboard is the distance between the surface of the water and the bottom of the user's mouth. With more buoyancy, the freeboard will be higher. In rough water with big waves, a greater amount of freeboard will make it easier to keep your head above water.

A life jacket should be tested every year to ensure that it still fits properly and for signs of aging, such as fading or tears. As the jacket ages, the foam will disintegrate, or, in the case of a hole or a tear, fall out of the jacket. When a life jacket is past its useful life, it should be cut into tiny pieces before it's thrown away. This will prevent someone from finding and using a degraded life jacket.

Life jackets will not last forever, but good care and maintenance will help them work properly while you have them. Most life jackets may be washed by hand in mild detergent, and then they should be allowed to drip dry. Do not dry clean a life jacket, because the solvents and the heat can disintegrate the foam. Store the life jacket in a well-ventilated place.

In caring for a life jacket, it's important to avoid extreme heat, such as from clothing dryers, because this will quicken the disintegration of the foam. Life jackets shouldn't be left sitting out in direct sunlight. Compression, including using a life jacket as a pillow or a seat cushion, will also compromise the integrity of the foam.

Inflatable devices require slightly different maintenance than naturally buoyant life jackets. Inflatable PFDs must have full cylinders of carbon dioxide, and the cylinders must be replaced each time the jacket is activated. An inflatable device must be regularly checked for leaks. Indicators on inflatable jackets will glow green when the canisters of carbon dioxide are installed and ready for use. If the indicator is not glowing green, then the device is not approved by the Coast Guard for use. With an automatically inflatable jacket, the water-soluble device must be replaced as well. If the life jacket is never activated, the bobbin or pill should still be replaced every one to three years. Additional cylinders and stoppers are available in a re-arming kit.

Your life jacket is tested and ready to go, but do you really have to wear it? We'll take a look at the laws on life jackets in the next section.