The performance advantage of seat belt pretensioners is well documented. But what is the effect for child restraints ? Four categories of child restraint systems (CRS) with and without seat belt pretensioners on adult seat belts were tested, using the ECE 44.03 dynamic test. Outcomes were compared in terms of head excursion, head and chest deceleration, and Head Injury Criterion (HIC). A common type of pyrotechnic pretensioner was used. For infant restraints, pretensioned conditions caused a reduction in head excursion and HIC. Two forward facing toddler seats showed lower HIC, and one a large reduction in excursion. Pretensioning caused reductions in HIC for forward facing impact shield boosters and for belt positioning boosters. Three CRS were also tested in a pre-impact braking mode, with and without pretensioner. Here the differences were less pronounced. On the whole, pretensioners improved the outcome for CRS, in particular for designs whichdid less well in the "normal" mode. The tests revealed no major ill effects for these models of CRS when used in adult seat belts with pretensioners. (A)
Samenvatting