In terms of the halachos in Shulchan Aruch Orach Chaim Siman 85 (which places is it ossur to say Krias Shema) would a small room with just a shower head have the same dinim as a room with a toilet or a room with just a bathtub?
Answer:
Although the Rashba (7:418) writes that the main problem of a merchatz (bathhouse) is the fact that it is a dirty place, many agree that a shower room is considered like a cheder emtza'i of the Gemara, in which it is not permitted to speak divrei Torah, but permitted to think about them.
For sources see Yabia Omer (5:11).
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