A couch, which is meant for sitting or lying down, can contract tumah if a person who is a niddah or a zav/zavah sits or lies on it. In fact, many objects in the home may have the ritual status of tumah. However, since the destruction of the Beit Hamikdash, the laws associated with this type of tumah no longer have practical applications, and anyone may sit on a couch without concern regarding the ritual status of the couch.

Ashkenazi practice is that, when the wife is in niddah, a couple may not sit together at the same time on a seat where the movement of one person can be felt by the other. However, this restriction is not connected to the laws of tumah.