Seat Belt Types and Terminology








There are several different types of seatbelts used in modern cars and trucks. The three most widely used types of seat belts include: lap belts, shoulder belts, and combination lap and shoulder belts. Seat belts are frequently described by the number “anchor points” they have, i.e. the number of places where the seat belt system is anchored to the vehicle. The load from a seat belt is transferred to the vehicle structure at the anchor points. For example, a “two point” seat belt may be anchored to the seat structure and to the occupant’s door, while a “three point” restraint, like a lap / shoulder belt, would be anchored to either side of the seat near the occupants hips, and to the frame of the vehicle at the door pillar.

Seat belts are also typically described by the part of the body that is restrained. For example, a “lap-only” belt goes across the occupant’s lap only and does not restrain the upper body. A lap-only belt would also be considered a two point restraint. Whether the belt operates manually or automatically is also used to describe the style of restraint at issue.

There are a number of different varieties and combinations that emerge from these descriptions. An automatic, two point, shoulder-only seat belt, for example, is one commonly seen on both the driver and passenger side of sedans produced from the mid-1970’s through the 1990’s. With that arrangement, the occupant would get into the vehicle and the belt would automatically slide along a track in the door, stopping above the outside shoulder and restraining the person across the chest. This variety of seat belt system may also include a manual, lap-only component that the occupant would need to fasten themselves.

Most vehicles manufactured today include three point, manual, lap / shoulder safety belts. In fact, as of September 2007, federal law requires that all manufacturers provide three point safety belts for all seats in new passenger vehicles. As technology and public awareness continue to develop, it is likely that seat belt systems with more than three anchor points will become common place. Five-point safety belts are already being used in race cars and certain child safety seats.