In order to ensure that a child can not pass between the bars of the balcony, the distance between the bars must not be more than 10 cm. If the distance is greater, attach a plexiglass or wood plate for shielding the entire length and height. You can also weave a cloth firmly between the bars. Make sure the cloth is properly attached tightly to the bars. Note that there is no climbing opportunities on the balcony stand as planters, chairs, etc.