[If] blood mixed with water — if it has the color of blood, he is required to cover [it]. [If] it mixed with wine, we view it as if it were water. [If] it mixed with the blood of an animal or with the blood of a beast, we view it as if it were water. R’ Yehudah says: Blood cannot nullify blood.

[If] blood splashed or is on the knife, one is required to cover [it]. Said R’ Yehudah: When? When there is no other blood but that, but if there is blood other than that, he is exempt from covering [it].