Reference: Liqaa. al-Baab al-Maftooh, Volume 68, Page 188
Question: If a person finished reciting Soorah al-Faatihah in the quiet prayer (Zhuhr and ‘Asr), should he say ‘aameen’ or not?
Response: When he finishes [reciting Soorah] al-Faatihah, he should say “aameen” in [both] the quiet and audible prayers, whilst doing so audibly [only] in the audible [Fajr, Maghrib and ‘Ishaa] prayers.
