Neuroscience Research Australia, Randwick, NSW, Australia.
Faculty of Medicine, The University of New South Wales, NSW, Australia.
Traffic Inj Prev. 2022;23(5):244-249. doi: 10.1080/15389588.2022.2048825. Epub 2022 Mar 25.
It is often assumed that a child restraint with a five or six-point internal harness provides greater protection for children in frontal crashes than a booster seat with a lap-sash seat belt. However, most research comparing these restraint types has focused on protection for children aged up to approximately 3-4 years of age. Recently, harnessed child restraints for older children up to approximately 8 years of age have become available, but there is little data on their performance compared to booster seats for children over 4 years of age. This study aimed to compare frontal crash performance of a series of harnessed child restraints for children aged 4-8 years to booster seats.
Four large harnessed child restraints (Type G in the Australian Standard, AS/NZS 1754:2013) and six high back booster seats (Type E in AS/NZS 1754:2013) were tested in frontal impact on a deceleration sled. Head and pelvis accelerations were recorded and head excursions were measured from high speed video.
Head excursion was an average of 92 mm greater in the large harnessed child restraints than the high back booster seats. The initial position of the head in Type G restraints, an average of 58 mm further forward compared to Type E boosters, was the main contributor to the larger head excursion during impact. Conversely, peak head accelerations in the impact phase were, on average, 37.2 g lower in the large harnessed child restraints than the high back booster seats.
These data suggest that recommendations for harnessed restraints and booster seats for children aged 4-8 years is not as obvious as is sometimes assumed. Harnessed restraints allow greater head excursion in frontal impacts, potentially increasing the chances of head impacts, especially in vehicles with limited clearance between the restraint and the seat in front. The likelihood, and types of, incorrect use that occur in each restraint type, the vehicle occupant space, and the restraint's crash performance under ideal conditions should be considered in recommending restraints for these older children.
人们通常认为，与配备有腰部安全带的增高座椅相比，具有五点或六点内部安全带的儿童约束系统在正面碰撞中为儿童提供了更大的保护。然而，大多数比较这两种约束类型的研究都集中在保护年龄在 3-4 岁左右的儿童上。最近，为年龄在 8 岁左右的较大儿童提供了配备有安全带的儿童约束系统，但关于它们与 4 岁以上儿童的增高座椅相比的性能的数据很少。本研究旨在比较一系列适用于 4-8 岁儿童的配备有安全带的儿童约束系统与增高座椅的正面碰撞性能。
在减速雪橇上对四个大型配备有安全带的儿童约束系统（澳大利亚标准 AS/NZS 1754:2013 中的 G 型）和六个高背增高座椅（AS/NZS 1754:2013 中的 E 型）进行了正面冲击测试。记录头部和骨盆的加速度，并从高速视频中测量头部的位移。
在大型配备有安全带的儿童约束系统中，头部位移的平均值比高背增高座椅大 92mm。在 G 型约束系统中，头部的初始位置比 E 型增高座椅向前移动了 58mm，这是导致在冲击过程中头部位移更大的主要原因。相反，在冲击阶段，大型配备有安全带的儿童约束系统中的头部峰值加速度平均比高背增高座椅低 37.2g。
这些数据表明，对于 4-8 岁儿童的配备有安全带的约束系统和增高座椅的建议并不像有时假设的那样明显。在正面碰撞中，配备有安全带的约束系统允许更大的头部位移，这可能会增加头部碰撞的可能性，尤其是在约束系统和前排座椅之间的间隙有限的车辆中。在推荐这些较大儿童使用的约束系统时，应考虑到每种约束系统类型的错误使用的可能性和类型、车辆乘客空间以及在理想条件下约束系统的碰撞性能。
