The main purpose of the lap belt in a three point restraint system is to transmit the large loads generated, due to deceleration involved in automotive collisions, to the strong pelvic bones. However, existing seat/belt systems often do not ensure adequate positioning of the lap belt. This may cause the lap belt to lie over the abdomen, resulting in serious abdominal injuries. There are many factors which affect the fit of any particular seat/belt system. However, the location of the lap belt anchorages has been found to be one of the most significant factors.

This paper describes the development and evaluation of two prototype belt systems (PBS) for the right front seating position of contemporary passenger vehicles. The purpose of these systems is to demonstrate the applicability of belt anchorage relocation in a production vehicle, as well as confirming the expected improvement in lap belt fit.

The two vehicles chosen for modification were a 1982 Chevrolet Malibu (bench style seat) and a 1982 Ford Escort (bucket style seat).

The quality of belt fit for both modified vehicles was evaluated with human subjects as well as by a newly developed "Belt Configuration Test Device" (BTD) and found to be favourable.