FactSentinel

Seatbelts are among the most effective safety technologies ever introduced in motor vehicles. The U.S. National Highway Traffic Safety Administration (NHTSA) estimates that lap and shoulder belts reduce the risk of fatal injury to front-seat passenger car occupants by 45 percent, and the risk of moderate to critical injury by 50 percent. For light truck, SUV, and van occupants, the estimated reduction in fatality risk is higher, at around 60 percent. The Centers for Disease Control and Prevention cites similar figures, and the World Health Organization reports that wearing a seatbelt cuts the risk of death among drivers and front-seat passengers by roughly 45 to 50 percent.

The reasoning is rooted in physics and in decades of crash data. In a collision, an unrestrained occupant continues moving at the vehicle's pre-crash speed until striking the steering wheel, dashboard, windshield, or other occupants, or until being ejected from the vehicle. Ejection is especially deadly. A belt spreads crash forces across the strongest parts of the body, the pelvis and rib cage, and keeps the occupant in the protective space of the vehicle. Estimates come from comparing outcomes of belted and unbelted people in real-world crashes, so they are approximations rather than exact values.

A common misconception is that being thrown clear of a wreck improves survival odds, but ejected occupants are far more likely to die. Another myth is that belts are unnecessary at low speeds or in cities, even though serious injuries occur at modest speeds. Belts also work together with airbags, which are designed as supplemental protection and can be less effective without a belt.