19. The Cleanliness of Where We Pray

5:7 Excrement that has dried up to the point that it crumbles apart is considered like dirt (so long as it has also lost its offensive smell). If it is frozen from the cold, it is still treated as excrement since it will return to its previous state when thawed. Excrement covered by snow is considered legitimately covered for the purposes of reciting prayers or learning Torah in its vicinity.

5:8 In order to recite prayers and study Torah, one must distance himself four cubits from the smell of excrement that is behind him. (Please note – we must distance ourselves four cubits from the odor, not from the object itself! A cubit is about 18 inches so four cubits is about six feet.) If one cannot smell it, he should still distance himself this amount but if there actually is no smell then four cubits from the excrement itself is sufficient. However, if the excrement is in front of a person, he must move so that it is no longer in sight. If it is dark out, a person must move the distance he would have to move by day in order to avoid seeing it. (The same applies if one is blind – see Rema on Orach Chaim 79:1.) If the waste matter is to one’s side, he should rotate so that it ends up behind him; in a pinch one may treat excrement to the side the same as if it were behind him (Mishnah Brurah 79:5). All authorities agree that when it comes to excrement, turning one’s face aside is insufficient (Biur Halacha on Orach Chaim 79:1).