Does Prayer Become Invalid if a Covered Body Part Is Exposed?

Does prayer become invalid if a covered body part is exposed?

If an organ that should be covered is uncovered unintentionally during prayer that is being established in congregation or individually, prayer is not nullified if that body part is covered back immediately. The prayer is invalidated if the uncovered part is at least one fourth of the organ and stays uncovered for long enough to perform a rukn (to say Subhanallahi’l-azim). If a person uncovers a body part deliberately, prayer will be invalid (Marghinani, al-Hidayah, I, 290-291).

Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS