May one wash rags or hand towels during the nine days?
If one has run out of clean rags or towels, then he may wash them up until the week of Tishe Beav. They may not be washed during the week of Tishe Beav. However, some are lenient if they get dirty extremely often and are changed daily. Practically, one may be lenient for hygienic purposes.
Explanation: The Poskim rule that up until the week of Tisha b’Av one may wash his garments if he no longer has any clean ones available. However, by the week of Tisha b’Av this is forbidden to be done, and no exception is mentioned. Nonetheless, some Rabbanim argue that all clothing that get dirty very quickly may be laundered during the nine days just like children’s clothing. In the event that there is some reason of Kavod Habriyos relevant certainly one may be lenient like this approach.
Sources: See Moed Lekol Chaiy 10:11; Ben Ish Chaiy Devarim 6 [permits handkerchief which gets dirty daily from blowing nose]; Nitei Gavriel 35:7 and 18 footnote 11 [regarding womens cooking clothing]; Piskeiy Teshuvos 551 footnote 106 [regarding hospital sheets]; See regarding children’s clothing which constantly becomes dirty with feces and urine, that they may be laundered even the week of Tisha B’av: Rama 551:14; [Levush 551; Kaf Hachaim 551:178