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How Life Jackets Work


Life Jacket Usage
A waterskier floating in the water
A waterskier floating in the water
Andy Whale/Photonica/Getty Images

The U.S. Coast Guard has several federal requirements regarding flotation device use. Recreational boats must carry one wearable PFD for each person aboard the boat. One throwable PFD, such as a ring or a cushion, must be present on any boat 16 feet and longer, although canoes and kayaks are exempt from this rule. These devices should be readily accessible, meaning they're not in the bottom of a trunk or tied to the side of a boat.

In addition to these federal regulations, many states have laws regulating the use of life jackets, particularly for children and for activities such as water skiing. However, there is no law that a person has to wear a life jacket. In 2005, the Coast Guard found that only about 23 percent of recreational boaters were wearing personal flotation devices [source: U.S. Coast Guard].

Many states have tried to pass laws mandating life jacket use for all adults, but they have not been successful. Those who support mandatory rules for adults point to laws regarding seat belts and helmets as instances where legislation increased use and saved lives. Boating, however, is seen as more of a leisure activity, where those who participate are choosing to do so at their own risk. In a 2002 survey, 55 percent of boaters disagreed that all persons should be required to wear a flotation device while aboard a boat [source: U.S. Coast Guard]. Boaters were more likely to support enforcing laws related to boating under the influence or stricter control of reckless boaters.

Some people may choose not to wear a life jacket because they are strong swimmers, and they count on providing additional buoyancy through actions such as treading water. A life jacket has additional safety purposes to consider:

  • A life jacket will help protect a person against hypothermia, an important threat when a rescue might be slow in coming. The jacket will help keep a person's head above water, so it stays dry, and it will help hold in body heat. Instead of exerting heat and energy in treading water, people wearing life jackets can pull their legs into their chests, which slows the escape of body heat.
  • Most life jackets are brightly colored to aid in rescue efforts.
  • Life jackets can absorb some of the impact of a fall and minimize injuries.
  • Few people plan to fall overboard. When someone ends up in the water who didn't expect to be there, a life jacket can provide some valuable time in adjusting to the shock. Most people thrash around when panicked; a life jacket helps the user right himself and keep the head above water.

For more information on life jackets and how other things float, check out the links on the next page.