Yosef Karo

“ He should not sit on a bed that is set aside for her, even if it is not in front of her. Rama: And it is forbidden to sit on a long bench that sways and is not connected to the wall when his wife who is in Niddah sits on it. And there are those who permit when another man acts as a buffer and sits between them. ”

“ He should not touch her even with his smallest finger and he should not stretch out from his hand to her hand anything, and he should not receive anything from her hand, because perhaps he would touch her flesh. ”