[If a woman] lent her tunic to a gentile woman or to a niddah, she may attribute [a stain] to [the borrower].  [If] three women wore a single tunic, or sat on a single bench, and blood was found on it, all of them are tamei. [If] they sat on a stone bench or on the seat of a bathhouse, R’ Nechemyah rules [them] tahor, for R’ Nechemyah was wont to say: Anything that is not susceptible to tumah is not susceptible to bloodstains.

[If] three women were sleeping in one bed and blood was found beneath one of them, they are all tamei. [If] one of [the women] examined [herself] and found herself to be tamei, she is tamei and the other two are tahor. And they may attribute [the stain] to one another; but if they were unfit to menstruate, we treat them as though they were fit to menstruate.

[If] three women were sleeping in one bed, and blood was found beneath the middle one, all of them are tamei. [If blood was found] beneath the inner one, the two inner ones are tamei and the outer one is tahor. [If blood was found] beneath the outer one, the two outer ones are tamei and the inner one is tahor. R’ Yehudah said: When [is this ruling valid]? When they ascended by the foot of the bed. But if the three of them ascended by going over [the outer one], all of them are tamei.  [If] one of [the women] examined [herself] and found herself to be tahor, she is tahor and the [other] two are tamei. [If] two [of them] examined [themselves] and found themselves to be tahor, they are tahor and the third [woman] is tamei. [If] all three of them [examined themselves] and found themselves to be tahor, all of them are tamei.  To what is this comparable? To a tamei heap that got mixed up with two tahor heaps, and they searched one of [the heaps] and found it to be tahor, it is tahor and [the other] two are tamei. [If they searched] two and found them to be tahor, they are tahor and the third [heap] is tamei. [If they searched] all three of them and found them to be tahor, all of them are tamei; [these are] the words of R’ Meir, for R’ Meir says: Anything that is in a presumptive state of tumah remains forever in its [state of] tumah until it becomes known to you where the tumah is. But the Sages say: He searches until he reaches bedrock or virgin [soil].

Seven detergents are applied to the bloodstain: raw saliva, split-bean water, urine, nesser, boris, kimunia, and ashlag. One immersed [the garment] and prepared tohoros upon it: [If] he applied the seven detergents to [the stain] and it did not come out, it is dye, the tohoros are tahor, and he need not immerse [the garment]. [If the stain] came out or dimmed, it is a bloodstain, the tohoros are tamei, and it is necessary to immerse [the garment].