However one who has reached puberty is permitted to go down before the ark provided that he is doing it only occasionally. But he may not be appointed officially.
And this is forbidden even where there is already a chief cantor and but this one is merely being appointed as an assistant to substitute for him on specified occasions.
And this applies only if he is doing it by himself. However if he is doing so as part of a group, then from the time that he knows how to lift his hands he is allowed to do so with them.