During “Shabua She’hal Bo Tisha B’Ab,” or the week in which Tisha B’Ab falls (until the day of Tisha B’Ab), it is forbidden to wear freshly-laundered clothing. Therefore, before the week of Tisha B’Ab one must wear for at least a brief period all the garments he plans to wear during that week. When Tisha B’Ab falls on Sunday, of course, there is no “Shavua She’hal Bo,” since Tisha B’Ab is observed on the very first day of the week. However, many people overlook the obvious fact that the restrictions of “Shabua She’hal Bo” certainly apply on Tisha B’Ab itself. Therefore, in such a case, one must ensure to prepare garments ahead of time for Tisha B’Ab. Presumably, people will be wearing their Shabbat clothing on Shabbat and will want to change into weekday clothing on Sunday morning. One must make a point of wearing the clothing he plans to wear on Sunday at some point before Shabbat, so that he will not wear freshly-laundered clothing on Tisha B’Ab.
One of the prohibitions that apply on Tisha B’Ab is that of “Rehisa” – washing. The Shulhan Aruch rules that one may not wash his hands on Tisha B’Ab unless they became dirty. The prohibition of “Rehisa” applies only to a “Rehisa Shel Ta’anug” – washing performed for enjoyment purposes, and therefore it is permissible to wash for the purpose of removing dirt and the like.
This Halacha gives rise to the question of whether one may wash dishes on the day of Tisha B’Ab. This is especially pertinent when Tisha B’Ab falls on Sunday, in which case one may want to wash the dishes from Se’uda Shelishit (the third meal of Shabbat). Halacha forbids washing the dishes used for Se’uda Shelishit on Shabbat itself, since they are not needed for Shabbat, and washing them would thus constitute “Hachana” (preparing on Shabbat for after Shabbat). Hence, when Tisha B’Ab begins, one will have the soiled dishes leftover from Se’uda Shelishit in his home and will likely want to wash them. As one washes dishes, of course, his hands come in contact with water and are washed, and the question thus arises as to whether this may be done on Tisha B’Ab, when hand washing is forbidden.
At first glance, we might claim that since this washing is not performed for enjoyment purposes, it does not fall under the prohibition of “Rehisa.” It appears, however, that the Shulhan Aruch made an exception only with regard to washing dirt off one’s body, and not for removing dirt from some other object. Accordingly, Rav Pinhas Zevihi (contemporary scholar in Israel), in his work on the laws of Tisha B’Ab (p. 178; listen to audio recording for precise citation), ruled that one should refrain from washing dishes on Tisha B’Ab until after midday. And even after midday, one should minimize direct contact with water as much as possible. This is also the ruling of Rabbi Haim Kanievsky.
It should be noted that it is entirely permissible to ask a gentile, such as a housekeeper, to wash one’s dishes on Tisha B’Ab, even before midday.
Summary: One may not wear freshly-laundered clothing during the week in which Tisha B’Ab falls, and on Tisha B’Ab itself. When Tisha B’Ab falls on Shabbat, in which case there is no “week” of Tisha B’Ab, one must prepare clothing for Tisha B’Ab by wearing a change of clothes for a brief period at some point before Shabbat. It is forbidden to wash one’s hands on Tisha B’Ab unless they become dirty. One should refrain from washing dishes on Tisha B’Ab until midday, including the dishes from Se’uda Shelishit, and even after midday one should minimize contact with water while washing dishes. One may have his non-Jewish housekeeper wash dishes even before midday.
