Booster seats are recommended for children approximately 4 to 10 years old, with more specific recommendations according to their size. The booster seat improves the geometry of the lap and shoulder belts, and allows the child's lower limbs to bend at the knees eliminating the need to slouch. Without a booster seat, children will also often place the shoulder belt under their arm or behind their back. This paper presents sled tests with a 6-year old child dummy in several restraint conditions. In addition to correct booster seat use, the dummy is restrained with a three-point belt, and with the shoulder belt either behind the back or under the arm. Dummy injury measures illustrate the increased injury risk due to misuse of the shoulder belt. In support of the sled test findings, data from the CIREN (Crash Injury Research and Engineering Network) database illustrate injury trends resulting from these misuse scenarios. (Author/publisher)
Abstract