What are the characteristics required of the person who will recite the iqamah in congregational prayer?

The person who will recite the iqamah must be free from ritual impurity, of sound mind, and male. Accordingly, it is considered disliked (makruh) for someone who is without ablution, in a state of major impurity (junub), insane, intoxicated, or a woman to recite the iqamah. It is recommended (mustahabb) for the person reciting the iqamah to be a righteous individual. (Ibn Nujaym, al-Bahr, 1/268-270; ‘Aliyy al-Qari, Fath bab al-‘inayah, 1/227)

The person reciting the iqamah must at least be discerning (mumayyiz), meaning able to distinguish between good and bad. This ability generally begins at around age 7 and continues until puberty. The adhan and iqamah recited by a child who is not yet discerning are not valid. The adhan and iqamah recited by discerning children are valid. However, it is considered more virtuous for the iqamah to be recited by someone who has reached puberty. (cf. al-Sarakhsi, al-Mabsut, 1/138; al-Fatawa al-Hindiyyah, 1/54; Ibn ‘Abidin, Radd al-Muhtar, 1/391-393)

Source: T.C. Diyanet İşleri Başkanlığı, Din İşleri Yüksek Kurulu