The objective of this paper is to compare the morphology of children aged from 3 to 15 years old with actual Child Restraint System dimensions.

First, an anthropometry study has been performed on about 2000 French children aged from 3 to 15 years old. For each subject, 15 external measurements have been acquired in particular in sitting position. They include classical dimensions like weight and heights (head-seat, shoulder-seat, etc) but also new data concerning for example the sternum length, the xyphoid angle or the thorax and abdominal widths.

In a second step, 13 dimensions have been measured on about 30 actual CRS. These CRS concern only forward facing system such as booster seat and they represent the different standard groups:​ 0+,1, 2, 3. To complete the geometry acquisition, 6 dimensions concerning the back seat of 6 different vehicles have been measured. Dimensions have been focused in particular on the belt position in the car or in the CRS. For each child anthropometric dimension, the 5th, 25th, 50th, 75th and 95th percentiles curves are given and discussed. Then, these dimensions are compared with the measurements performed on the CRS and on the vehicles. In particular, data concerning the belt position regarding the children morphology along ages are detailed. The location of the belt on the shoulder is more specifically evaluated.

Results highlight that some of the CRS appear as unsuitable regarding the children anthropometry. This article shows for example a gap between the CRS classification based on children weight.