Preparations for Immersion on the Night After Tisha B'Av
Question
Answer
Shalom Rav
According to the Ashkenazi custom, preparations should ideally be made on the eve of Tisha B'Av, including bathing, cutting nails, etc. On the night after the fast, one should only take a regular shower, comb the hair, and inspect the entire body.
This is not to ease the organization but to ensure that the preparations are done at a time when immersion is not yet possible, allowing for a calm washing and inspection.
According to the Sephardic custom, preparations should be made on the night after the fast, and there is no permission to advance them to the eve of the fast. The reason is to ensure that the preparations are close to the immersion.
Source
Shulchan Aruch, Orach Chaim, Siman 554, Se'if 8, Mishnah Berurah there Se'if 8.
Shulchan Aruch, Yoreh De'ah, Siman 199, Se'if 4, Shach there Se'if Katan 6 and Se'if Katan 9.