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How can we tell if a child has outgrown the child car seat's harness?

How can we tell if a child has outgrown the child car seat's harness?


A lot of doubts arise during the stages at which children should be using a child restraint system when traveling by car. The most typical question is usually regarding which type of child seat is best for each stage, and another concern is often about when it is a good idea to switch to a better model or a larger one.

For a lot of parents, a closely related problem is how to tell when the child has outgrown the CRS we are using. How can we tell when the harness is too small for the child? Why is it so important to know this and what are the implications?

How do we know when a child has outgrown the child car seat's harness?

The answer will depend on the type of CRS we are using. As a general rule, a child restraint system has become too small for the child when their head extends above the back of the seat.

This is very important because whilst the child's head does not exceed the height of the seat they will be completely protected in the event of a collision. The seat will cushion the child from any blow the seat might receive due to the forces exerted on it in a crash. If the seat has side protection, which is highly recommendable, all angles will be fully protected.

With regard to the harnesses for Groups 0, 0+ and 1, they can be adjusted in a number of ways in order to adapt them to the child's height and size. lf the CRS has 3 positions for the harnesses, we could, for example, choose a higher position each time the upper part of the belt ends up being lower than the child's shoulders.

Once all possible adjustable positions have been used it is time to change the seat for a larger one.

The reason for doing so is because the harnesses are much safer when they fit snugly and are at right angles to the seat's backrest. If the child's shoulders are at a higher level than the point at which the harness comes out of the backrest the seat will provide less protection than if the child's shoulders were lower down.

Nevertheless, we should not forget the main reasons for replacing a child restraint system, which you can look at in more depth in this article.

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