The crash test dummy family has a new member, an anthropomorphic test device meant to be representative of a 10-year-old child, according to the National Highway Transportation Safety Administration.

The dummy was found to sit in a seat like a human child and don the belt like a human child, said a February report from the NHTSA.

The new dummy, designated HIII-10C is meant to fill in a gap in the line of crash test dummy children. While the NHTSA already had dummies for newborn infants, 12-month-olds, three-year-olds, six-year-olds, apparently euphemistically termed weighted 6-year-olds, and 12-year-olds, which can stand in for 5th percentile adult women, the agency was missing a 10-year-old dummy. And so, the NHTSA brought into the world a new middle child for the crash test dummy, a February report from the agency said.

The new dummy weighs 78 pounds. The NHTSA uses the child crash test dummies to evaluate the crashworthiness of booster seats and other restraints in a 30 mph frontal sled test. The Society of Automotive Engineers Dummy Family Task Group began development of the new 10-year-old dummy in 2000.

One of the primary difficulties in producing the new 10-year-old crash test dummy came from how to replicate chin-to-chest contact (which had been of greater force in earlier versions of the dummy than in real life), while still ensuring that the dummy would sit in a booster seat the way actual children do.

The agency would up working with the University of Michigan Transportation Research Institute to develop a new procedure for fitting the new crash test dummy to booster seats in a way that mimicked how actual children sit in them. The agency tested the new dummy with 34 different booster seats.

The new dummy and rules associated with it from the NHTSA allow the agency to expand Federal safety standards for child restraint systems (CRS) to systems meant for children weighing up to 80 pounds (it was previously limited to 65 pounds). This interest goes hand-in-hand with efforts to prolong CRS use among children who have outgrown their child safety seat, but who cannot adequately fit a vehicles lap and shoulder belt system, the NHTSA report said.