The performance of tethered and untethered forward facing child restraints

Serious neck injury to children restrained in forward facing child restraint systems involved in crashes of moderate severity has been reported by several researchers in Europe and North America. No cases of similar injury have been reported in Australia for children correctly restrained in forward facing child restraints. The major difference between the forward facing restraints used in Australia and those used in Europe and North America is the universal use of a top tether strap in Australia. The rationale for this requirement of a mandatory top tether has always been that it reduces the likelihood of head contact with the vehicle interior. This paper describes a sled test program to investigate the performance of forward facing child restraints with a variety of top tether geometries. The restraint system performance was assessed using the CRABI six month child dummy.The results of the study indicate, that as well as reducing head excursion, a top tether, with the right high mounted geometry, significantly reduces head acceleration and neck loads in frontal impacts.