Answer
In this case, we recommend, as do all international safety experts, that you stop immediately in a safe place, fasten the buckle once more and tell the child not to open it and the reason for this. It is always a possibility that an inventive, handy or strong child will open the buckle. If the force required to open the buckle were to be considerably increased to make it impossible for the child to open it himself, this would be contrary to the legal safety standards. The position of the buckle, the colour of the button, and the operating or opening force are all laid down in European standards. In the case of an accident, someone providing assistance without any knowledge of car seats must be able to see immediately how to release the child from a car seat in an emergency.