Seat belts prevent injuries and fatalities. Wearing a seat belt while traveling in a car can help reduce the chance of injury or death as a result of a crash by as much as 50 percent.
As of June, 2014, mandatory seat belt laws exist in the District of Columbia and all states except New Hampshire, while child safety seat laws exist everywhere in the United States. Children are required to be restrained in proper devices or booster seats. Older children may be permitted or required to use adult seat belts. The age at which a child must use an adult belt varies from state to state.