20th of January 2014
In the European market there are currently two main restraint systems available for car seats intended for toddlers of approximately 1 to 4 years old: the 5-point harness and the shield system. The aim of this statement is to explain why Maxi-Cosi considers that it is better to protect a child in a toddler seat with a 5-point harness, as according to numerous tests.
There are 3 main reasons why Maxi-Cosi chooses to equip its toddler car seats with a 5-point harness:
- Crash forces are transferred from the seat to the child’s rigid body parts that can take high loads: shoulders and hips/pelvis bone.
- Children are secured more firmly and therefore remain in the safest position in the car seat during all types of accidents (frontal or side impacts, but also roll-over accidents).
- A 5-point harness offers easy adjustment to the growing child and a perfect fit for children of all sizes and shapes.
Safer deceleration by restraining rigid body parts
A 5-point harness works with 5 main attachment points that make sure that children are restrained by the rigid parts of their body: shoulders and hips. The 5-point harness transfers the crash forces from the harness to the rigid points of the body and into the seat. Dorel’s experience with a 5-point harness shows that a child’s soft parts (abdomen area) are better protected and do not have to endure high loads. This is a natural way to secure a body.
Soft parts of a body may not withstand the forces of a crash in the same way as rigid parts do. When a child is restrained by its soft lower abdomen, he/she can fold over the belt or object, and that belt or object can intrude into the abdomen area.
With the current crash test dummies (both P as Q dummy types) the loads on the rigid parts of the body can be analysed in detail. The limits of the forces that these body areas can withstand have been established. All car seats developed by Dorel are designed so that the forces are optimally distributed and that they remain within these limits. Currently it is not possible to measure the loads on the soft lower abdomen area, as the current crash test dummies are not equipped with sensors in these areas.
The effects of the loads on the soft abdomen area and the chest area when using shield systems and booster seats for children are not sufficiently known yet. Therefore, the United Nations has assembled a Task Force consisting of international experts to conduct a research study with the objectives to establish injury limits and assess the overall risks for children. The group is chaired by Child Seat Expert Dr. H. Johannsen of the Technical University of Berlin.
Firm restraining to remain in the safest position
Although crash tests are designed to simulate real accidents as accurately as possible, accidents are more complex than crash tests.
In the case of a car accident where different forces are applied (for instance a roll-over), there is a risk of submarining or ejection of the child from the car seat. The 5-point harness makes sure that the child is tightly secured by a one-pull movement, and keeps the child in the safest position within the protective seat shell, whatever the accident may involve.
A car seat that passed ECE R44-04 legislation showed insufficient restraining capabilities during a simulated roll-over test. Crash tests by UTAC (independent testing organization for the automobile industry) have showed that after two full roll-overs, the dummy was ejected from a car seat with a shield systems. You can learn more in the video about the car seat roll over test for shield system and in the video about the car seat roll over test for 5-point harness.
To prevent such ejection from a car seat, an amendment has therefore been approved, which introduce a more severe test to better reproduce roll-over crashes. This amendment has been active since December 2013.
Perfect fit to the growing body
A 5-point harness is easy to adjust to different height positions and therefore offers a perfect fit for different body sizes. The shoulder straps can be easily adjusted in height. This positioning ensures that the forces applied in an accident are best transferred to the car seat shell and the rigid shoulder bones of the child.
Find here the full 5-point harness statement