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On a Torah level a woman is only tameh if she has a hargasha when she sees blood.[1] There is a major dispute as to what this includes and even further dispute nowadays when these signs aren't usually observed today.[2] Nonetheless, all poskim agree that today woman do become niddah on a Torah level even though she isn't sure that she had a hargasha at all.[3] Either way, the rabbis declared that any time a woman sees blood from her body she is tameh.[4] These laws apply equally to single and married women.[5] Additionally, if she sees the blood after it came out and is found as a stain it will also make her nidda[6] In the halachot of niddah a stain is called a ketem and the plural is ketamim.

What is a Hargasha?

  1. The most accepted definition of a hargasha is that if a woman feels that her mekor (usually defined as the uterus) opened that is a hargasha and when blood comes out that will make her niddah.[7]
  2. Alternatively, another definition of hargasha given by the poskim is feeling something liquid moving and exiting the body.[8]
    1. Many contemporary poskim hold that this hargasha is only if she feels an internal flow through the uterine opening and not a vaginal flow.[9] Others say that even if a woman feels a vaginal flow (from the vagina outside) that is also a hargasha. However, feeling an external dampness is certainly not a hargasha.[10]
  3. Lastly, some poskim hold that if the woman feels her body trembling that is considered a hargasha.[11]

Masked Hargasha

  1. There are also a few occurrences which Chazal state could be confused with a hargasha. Therefore, if blood is found at one of these times according to many poskim there is a concern that there was a hargasha even if she didn't feel one. These examples include: going to the bathroom, doing an internal bedika, and having relations[12]
    1. According to many poskim if a ketem is found within a short time period after going to the bathroom or relations there is a concern that the ketem is really a result of a hargasha and as such it is tameh on a biblical level, in which case there are no leniencies of ketamim. However, other poskim aren't concerned about this.[13]
    2. If a woman sees blood on toilet paper or in the toilet after going to the bathroom, she should consult with a doctor and rabbi. Some poskim hold that the blood on the toilet paper isn’t an issue of a ketem since the toilet paper isn’t mekabel tumah. Additionally, the blood in the water or on the toilet isn’t an issue of ketem since they aren’t mekabel tumah. Other poskim hold that we can't employ the leniencies of ketamim since she saw this ketem right after going to the bathroom and perhaps this blood came with a hargasha and she didn’t realize.[14]

If there is a Hargasha Without any Blood

  1. If a woman felt her mekor open and didn't find any blood she is nonetheless tameh.[15] if she's not sure if she had such a hargasha she's tahor.[16] If she checks immediately and doesn't find any blood there is a dispute if she is tahor.[17]
  2. If a woman felt a liquid exiting her body or a trembling of her body and didn't find any blood she is not tameh.[18]

Hargasha Nowadays

  1. Most women today do not feel the hargasha described by earlier poskim.[19] All the poskim conclude that nonetheless woman today are tameh on a biblical level for a few reasons.[20]
  2. Some poskim hold that feeling an ache or the like prior to or during having a period, which is common, is a type of hargasha.[21]
  3. Some poskim hold that today we do have the same types of hargasha though we just don't realize it.[22]
  4. Some poskim hold that if she knew that the blood came from her body she is a Niddah on a biblical level.[23]
  5. Some poskim hold that every woman is automatically tameh on a biblical level. If she usually has a hargasha and one time doesn't then she's not tameh on a biblical level, however, since woman today never have a hargasha they are automatically tameh on a biblical level.[24]
  6. Some poskim hold that today the hargasha is defined by a normal type of seeing blood for a period, which is usually a normal amount of blood. However, if a woman is on a Mirena IUD she might still be a niddah on a biblical level even if she only sees a drop each month since for her that is the normal way of her period.[25]

Leniencies of Ketamim


  1. If a ketem is smaller than a garis it is tahor.[26] According to some poskim, the size of a garis is 19mm or the size of an American penny.[27] Others write that it is the size of a circle with diameter of 20 millimeters.[28]
    1. The needs for the size of a garis applies whether she saw the ketem on her body or a clothing. However, some poskim are strict if the ketem is found on her body.[29]
    2. Nonetheless, if there are two stains on the body less than a garis they combine together to be considered a garis to be tameh.[30]
    3. If two stains are found on a garment and are not connected to each other, they don't combine for a garis and so if each is less than a garis they are tahor.[31] If two red spots are connected with white or brown, then the two red spots add up, but we don't include the brown or white in the measurement of a gris.[32]
  2. The thickness of the blood on the stain is not relevant. If it is very thick but doesn't cover surface area of penny, tahor. If it is really thin but does cover surface area of a penny, then tameh.[33]


  1. The shape of the stain doesn't matter as long as its combined area is less than a garis.[34]
  2. Blood found on the body larger than a garis is tameh irrelevant of its shape.[35]
  3. If the ketem is found in a shape other than a circle the area is measure by the total area. If it is less than 2.83cm2 according to the first opinion above and less than 3.14cm2 according to the second opinion. An ellipse is measured by π*r1*r2, where r1 is the larger radius and r2 is the smaller radius, and a triangle by (h2*b)/2, where h2 is height from the base and b is the base.[36]


A Place that Does not Contract Tumah

  1. If a ketem is found on something that doesn't contract tumah it is tahor.[37] If a ketem is found on something that isn't mekabel tumah but is on top of something that is mekabel tumah according to some poskim is tameh, while according to other it is tahor.[38]
    1. For example, toilet paper isn't mekabel tumah and if a ketem is found on it, the ketem isn't tameh.[39]
    2. Pads according to most poskim aren't mekabel tumah.[40]
    3. Clothing which aren't made from wool or linen they aren't mekabel tumah if it is smaller than 3 by 3 tefachim.[41]
    4. Something attached to the ground, such as a toilet, isn't mekabel tumah and isn't susceptible to ketamim.[42]
    5. Clothing made completely out of nylon or polyester aren't mekabel tumah but if it is stitched with even a thread of linen it is mekabel tumah.[43] Practically, even if a clothing says it is "100% polyester" it is subject to ketamim since they almost certainly have some threads of cotton in them.[44] Some say that if the nylon is made into clothing it is mekabel tumah.[45]

Colored Material

  1. If a ketem is found on something colored it is tahor.[46]
  2. The poskim clarify that off-white or light-beige is also white for these purposes. Additionally, many poskim hold that extremely light pastel colors are difficult to be considered colored, while others hold that they're also considered colored.[47]
  3. Even if the ketem is found on an undergarment that is close to the body, if the garmet is colored, the stain is tahor.[48]
  4. If a garment is striped and the ketem is found partially on the white section and partially on the colored most poskim consider the area on the colored part to be ignored. However, if the ketem goes over a colored strip and is found on both sides on a white area, those two white areas combine for the size of a garis.[49]
  5. If it’s found on a garment that was colored but now faded and is bleached white, it should be shown to rabbi.[50]
Practice to Wear Colors
  1. Since a stain found on a colored garment is considered to be tahor, women should generally wear colored garments during their pure time.[51]

Different Locations on the Body

  1. If the ketem is found only on the woman's body it is only tameh if it is found on the inside part of the legs where they would touch when standing with legs together, heel, toes, or on the fingers or knuckles. Blood on the upper part of the body is tahor unless she woman laid down with her feet up, or did exercises, aerobics, headstands or other activities that can cause blood to appear on the upper body.[52]
  2. If the ketem is found both on her body and on her clothing, if she has a valid reason to suspect that ketem came from an outside source such as if she walked through a butcher's market the ketem is tahor, otherwise it is tameh.[53]
    1. If there is a ketem on her lower body and she has a wound on her neck or a bloody nose such that blood could fall on that spot lower on the body the ketem is tahor, however, if the wound is on the shoulder then the ketem can't be attributed to the wound.[54]
  3. If the ketem is only found on the clothing, if it is found by the area of the waist and below it is tameh. If it is on any clothing that is worn above the waist it is tahor because the stain wouldn't have come from her since it is above the waist. However, if she laid down with her feet up and there is a concern that the blood ended up on the upper part of her clothing the ketem is only tameh if it is found both on her clothing and her body but if it is just found on her clothing it is tahor.[55]
    1. If the stain is on the outside of her clothing, she is pure unless it is likely for uterine blood to be there like on a spot that touches that area when she puts on the garment or takes it off.[56]
    2. If upon waking up, she found a stain on her pajamas, a ketem on the upper part of the clothing is also tameh since the pajamas move all around. The same would apply to bedding such as a blanket or sheet[57]
    3. If the ketem is found on the sleeve that could reach that area if she were to bend over it is tameh.[58]
  4. If the ketem was found on a garment which wasn't checked that it was clean from stain beforehand a ketem found on it is tahor.[59] However, if it was laundered in between it is considered like it was checked and a ketem found on it afterwards is tameh since the laundry would remove the stain.[60]

If Her Ketem is Tameh

Becoming Tehora Again

  1. If a ketem is tameh and she was previously tahor she is now tameh and requires a hefsek tahara after waiting 5 days, according to Ashkenazim, and 4 days, according to Sephardim. After hefsek tahara she requires seven clean days known as shiva nekiyim with the requisite checks before she can go to mikveh.[61]


  1. If a woman became tameh on three occasions in a row because of a ketem that doesn't create a veset.[62] A woman who doesn't have a veset and became tameh because of a veset doesn't need to count an onah beynonit from the time she became tameh because of a ketem.[63]
  2. Furthermore, seeing a tameh ketem doesn't interrupt an upcoming veset day. For example, if a woman saw on the 1st of Nissan and then a ketem on the 15th her veset for the 30th of Nissan (onah beynonit) remains in place.[64]


  1. Shmuel in Gemara Niddah 57b. See also Mishna Niddah 58b.
  2. The Laws of Niddah v. 1 p. 70
  3. The Laws of Niddah v. 1 p. 74 fnt. 15 and Appendix A. See Pitchei Teshuva 190:1.
  4. Shach 190:1
  5. Rama 183:1. Torat Hashelamim 183:4 writes that although the gemara Nidda 31b says in the name of Rabbi Meir that the the reason to observe the separation from nidda for seven days is to keep the marriage fresh because when it becomes regular it becomes disgusting, so with the observance nidda it becomes like they're married anew, nevertheless this applies to single women.
  6. Shulchan Aruch 190:1
  7. Trumat Hadeshen 246, Shulchan Aruch YD 190:1, Taharat Habayit v. 1 p. 334, Shoshanat Ha'amakim 1:1
  8. Nodeh Beyehuda YD 1:55 holds that feeling a liquid exiting the body is a type of hargasha while the Chatom Sofer 1:145 argues that it isn't a type of hargasha. Sidrei Tahara 190:1 cites this as a dispute between the Shev Yakov who held that it wasn't a type of hargasha, and Maharshach who held it was. Rav Ovadia Yosef in Taharat Habayit v. 1 p. 14 holds that this isn't a type of hargasha.
  9. The Laws of Niddah v. 1 p. 76 citing Shaarei Tahara p. 8 quoting Rav Elyashiv and others. Chavot Daat 190:1 suggests this in understanding the concept of a hargasha of a flow.
  10. The Laws of Niddah v. 1 p. 76 citing Rav Moshe Feinstein in Igrot Moshe 4:17:7
  11. Pitchei Teshuva 183:1 based on Rambam Isurei Biyah 5:17, Shoshanat Ha'amakim 1:1
  12. Niddah 57b, Pitchei Teshuva 183:1 citing the Chavot Daat 190 and Sidrei Tahara
  13. The Sidrei Tahara 190:36 and 190:67 is concerned that there was a hargasha when she went to the bathroom or had relations and didn't feel the hargasha as the Gemara Niddah 57b discusses. If so, a ketem found afterwards is potentially deoritta and if so there are no leniencies of ketamim. This is codified in the Badei Hashulchan 190:104. However, Rav Ovadia Yosef in Taharat Habayit v. 1 p. 411 quotes the Pardes Rimonim who argues since the earlier poskim didn't mention this distinction. Furthermore, it might be an unlikely concern and she already has a chazaka of being tahora. Therefore, Rav Ovadia concludes that a ketem after these occurrences is treated like any other ketem. Rabbi Mordechai Willig (Niddah Shiur 93, 100) agreed with Rav Ovadia.
    • Chazon Ish 90:1 is lenient regarding a ketem after urination but not relations.
  14. Sidrei Tahara and Chavot Daat are concerned that any time a woman sees blood when she goes to the bathroom there’s a concern that there was a hargasha and she didn’t realize. This is based on their understanding of the Gemara Niddah 57b. See Machasit Hashekel 190:1 for the two ways of reading of this gemara. Some poskim argue that we're not concerned for a hargasha since it isn't common and she has a chazaka of being tahora. See Taharat Habayit v. 1 p. 411. Regarding toilet paper being mekabel tumah see further based on Igrot Moshe 3:53. Regarding the water in the toilet bowl, Rabbi Willig cited the Taharat Yisrael who was lenient since the water is connected to the water in the reservoir.
  15. Trumat Hadeshen 246, Shulchan Aruch YD 190:1
  16. Nodeh Beyehuda YD 2:118, Taharat Habayit v. 1 p. 334
  17. Pitchei Teshuva 190:5 quotes the Kereti Upeleti as holding that she is tahor and the Chavot Daat as holding that she is tameh.
  18. Chacham Adam 113:1 (cited by Pitchei Teshuva 190:3) writes that if a woman trembles and checks and doesn't find any blood she doesn't need to be concerned that she is tameh. Sidrei Tahara 190:3 adds that even for the hargasha of feeling a liquid exit the body it is possible that one can assume it was mey raglayim since that's more common than blood. Therefore, Taharat Habayit v. 1 p. 334 rules that the stringency of the trumat hadeshen that automatically a hargasha renders a woman tameh doesn't apply to the body trembling or feeling a liquid exit the body.
  19. Shev Yakov 40, Teshurat Shay 457, The Laws of Niddah v. 1 p. 70, Shoshanat Ha'amakim 1:4
  20. The Laws of Niddah v. 1 p. 74 fnt. 15, Shoshanat Ha'amakim 1:9 says when a woman menstruates we assume she had a hargasha. Therefore, even if she seemingly experienced no hargasha, she is rendered impure min hatorah.
  21. Rav Moshe Feinstein in Igrot Moshe YD 4:17:12, Maharam Shik YD 177, 184 based on Rambam Isurei Biyah 8:2. Mishmeret Hatahara (ch. 1 fnt. 15) quotes Rav Elyashiv as saying that we're concerned for this type of hargasha nowadays when feeling a hargasha isn't common.
  22. Aruch Hashulchan YD 190:61, Rav Moshe Feinstein in Igrot Moshe 4:17:12. The Laws of Niddah v. 1 Appendix A cites Chatom Sofer 177 as agreeing with this approach.
  23. Sidrei Tahara 190:93 in understanding Rashi and Tosfot. See also Maharam Lublin (responsa 2).
  24. Rav Elyashiv in Kovetz Teshuva 1:84
  25. Rabbi Mordechai Willig (Niddah Shiur 83) on and in his notes to The Laws and Concepts of Niddah by Rabbi Zvi Sobolofsky pg. 311
  26. Shulchan Aruch YD 190:5. The reason for this leniency is that it is common to find lice on the clothing and beds in the days of chazal and so a small amount of blood could be attributed to lice and not from her body. This is evident from the Gemara Niddah 58b. What about today when lice aren't as common? The Chatom Sofer 182 writes that the reason for the original institution of ketamim was because of taharot and even though we hold that it applies today even though the reason doesn't apply, we only apply the gezerah with the limitations that chazal would have had in their days. Therefore, concludes the Chatom Sofer, even though our lice are smaller than in the days of chazal we can continue to be lenient using their size of lice. Furthermore, Rav Moshe Feinstein in Igrot Moshe YD 3:46 fundamentally agrees but argues slightly differently; since chazal never stipulated that we are only lenient where lice are common it is evident that chazal only created a gezerah on a ketem that was larger than a garis. Since the original gezerah wasn't enacted upon a ketem smaller than a garis we can't add to that gezerah. Therefore, Badei Hashulchan 190:56 and Taharat Habayit v. 1 p. 391 conclude that we still use the leniency of a garis today even though lice aren't as common as it was in the days of chazal.
    • See the Sefer Eshkol (Hilchot Niddah, v. 1 p. 70) who writes that the reason that the Rif doesn't quote the halachot of ketamim is because it doesn't apply nowadays since we don't deal with taharot. The Raavad in Baalei Hanefesh (Shaar Haketamim p. 64) argues that nowadays ketamim still apply today. The poskim all accept the Raavad as is evident from Shulchan Aruch 190:1, yet the logic of the Eshkol supports the argument of the Chatom Sofer.
  27. Rabbi Forst in The Laws of Niddah v. 1 p. 189 writes that the poskim hold the size of a garis is the area of a circle with a diameter of 19mm or a penny.
  28. Taharat Habayit v. 1 p. 367 assumes 20mm.
  29. The Rambam (as understood by the Maggid Mishna Isurei Biyah 9:6) holds that a ketem on the body is tameh in all circumstances even if it is smaller than a garis. However, the Tosfot (58a s.v. keshirah), Raavad (Isurei Biyah 9:6), Rashba (Torat Habayit 15b), and Ramban (Hilchot Niddah 4:4) argue that a ketem less than a garis on the body is tahor since it could be from a louse. Hagahot Maimoniyot (Isurei Biyah 9:1) explains that the Rambam holds that it is less common for there to be lice on the body as much it is common for there to be lice on clothing. Alternatively, the Rambam is strict since the likelihood is that if the blood is found on the body it is from her and not from the outside (See Maggid Mishna above). Shulchan Aruch YD 190:6 writes the anonymous opinion like the Tosfot and quotes the Rambam as well. The Bach 190:12 follows the Tosfot on this question but the Shach 190:9 argues that we should be strict for the Rambam. Taharat Habayit v. 1 p. 375, Shoshanat Ha'amakim 1:20, Igrot Moshe 4:17:7, and The Laws of Niddah v. 1 p. 195 are lenient.
  30. The Shulchan Aruch 190:8 quotes the opinion of Tosfot (58a s.v. keshura) and the Raavad (Baalei Hanefesh p. 74) who hold that on the body the stains that are less than a garis can combine to be tameh. Though it isn't clear if the anonymous opinion in Shulchan Aruch disagrees with this opinion, as the opinion of the Rashba (Torat Habayit 18b) is that it is tahor, nonetheless the poskim are machmir. The Shach 190:9 is strict because anyways he holds like the Rambam, the Bach 190:12 is machmir, Taharat Habayit v. 1 p. 377 is machmir since either that is the opinion of Shulchan Aruch or it is the opinion of the majority of the rishonim, and The Laws of Niddah v. 1 p. 195 is strict. Chacham Ovadia Yosef (taharat habayit 1:8:4, yabea omer 8:16:2) writes that this is limited to when the stains on the body are in the same general vicinity
  31. Shulchan Aruch 190:8
  32. Badei Hashulchan 190:79, Shoshanat Ha'amakim 1:29
  33. Shoshanat Ha'amakim 1:28
  34. Smag (Lavin no. 111) writes that even if the blood is spread out in a line it is still tahor if it is less than a garis. Shulchan Aruch YD 190:5 codifies this. Shoshanat Ha'amakim 1:18 agrees
  35. The Rashba [(Torat Habayit 18b), Rosh (Niddah 9:2), and Rambam (Isurei Biyah 9:9) understand that even though the Gemara Niddah 58a asks whether blood found in an odd shape on the body is tameh and the gemara leaves it unresolved, we are strict because the Briatta implies that we're stricter with a stain found on the body. This is codified by the Tur and Shulchan Aruch YD 190:9. Shoshanat Ha'amakim 1:20 agrees
  36. Orot Hatahara p. 129
  37. The Mishna Niddah 59b cites a dispute between Tanna Kama and Rabbi Nechemya whether something that's not mekabel tumah is susceptible to a ketem. Rabbi Nechemya holds that it is not. Tosfot Niddah 59a explains that the only reason that ketamim make a woman tameh is because the ketem itself is tameh because of the blood on it. However, something that isn't susceptible to tumah isn't susceptible to ketamim. The Rashba Niddah 57b s.v. amar provides another reason; since most clothing are mekabel tumah, chazal didn't make a gezerah on something that wasn't common. Most rishonim accept the opinion of Rabbi Nechemya including Rashba (Torat Habayit 23b), Rosh (Niddah 9:2), and Rambam (Isurei Biyah 9:7) in opposition to the Raavad (Baalei Hanefesh p. 68) who holds that we follow the Tana Kama. Tur and Shulchan Aruch YD 190:10 are lenient like most rishonim.
    • Shach 16 quotes Tosafot that if something is mikabel tumat negaim that counts as mikabel tumah even though it’s not mikabel tumat met. Pitchei teshuva 190:17 says this is machloket achronim.
  38. The Sidrei Tahara 190:93 at the end writes that it seems if a ketem is found on something that isn't mekabel tumah which is top of something that is mekabel tumah she is tameh. Since the idea of ketem making a woman tameh is based on the idea that the blood makes the cloth tameh so too it should make the woman tameh, however, when the ketem is on a cloth that isn't mekabel tumah it is tahor. Yet, when the cloth is on top of something that is mekabel tumah the ketem makes the woman tameh since the cloth would make the item holding it tameh through tumat masa. However, the Pri Deah (Introduction 4) and Taharat Habayit v. 1 p. 410 argue that the poskim never mentioned this concern and apparently weren't concerned. Badei Hashulchan 190:99 writes both opinions and supports the Pri Deah from the Shulchan Aruch Harav.
  39. See Pitchei Teshuva 190:18 who cites a long discussion between the Nodah Beyehuda, Chatom Sofer, and others if toilet paper of their day was mekabel tumah. However, Rav Moshe Feinstein (Igrot Moshe 3:53) writes that our toilet paper is certainly not mekabel tumah since it is so thin that it falls apart and is unusable after it is used once. Taharat Habayit v. 1 p. 406, Shoshanat Ha'amakim 1:11 agree.
  40. Rabbi Mordechai Willig (Niddah Shiur 94 at the end) holds that pads aren't mekabel tumah even if they are attached to the undergarments with an adhesive. Taharat Habayit v. 1 p. 405 seems to agree. Mishmeret Hatahara (ch. 3 fnt. 30) quotes Rav Elyashiv as saying that since the pads are meant to be attached to the undergarments they become part of the garment and are mekabel tumah and as such a ketem on them is tameh.
    • The Nodah Beyehuda YD 2:105 held that the paper of his day which was made from worn out clothing is mekabel tumah because of being a thick cloth (levadim) even if it isn't woven. The source for this is the Rambam Kelim 1:11 and 22:2 and Tumat Tzarat 13:1, which in turn is based on Sifra Shemini 6:7:8 and Tosefta Negayim 5:1. Pads are made from cotton and as such aren't mekabel unless it is made into a thick cloth. Mishmeret Hatahara argues that even though the pads are thick they are't mekabel tumah since the Chatom Sofer 6:81 writes that a thick cloth is only mekabel tumah if it is made for a purpose of clothing but not if was made just to function as a piece of wood in order to clean or absorb liquid (Chullin 129a).
  41. Rambam Kelim 22:1. Mishmeret Tahara (ch. 3 p. 30), Pri Deah (Introduction 3), Taharat Habayit v. 1 p. 401, and Orot Hatahara p. 129. See Taharat Habayit who cites the opinion of the Bet Shlomo in explaining the Rash and Rosh Kelim 27:2 that even if other materials are even 3 by 3 etzbaot the cloth is tameh.
  42. Pitchei Teshuva 190:19, Taharat Habayit v. 1 p. 405, Badei Hashulchan 190:105, Orot Hatahara p. 130-2
  43. Igrot Moshe YD 3:53 holds that nylon is tahor since it is made from petroleum from under the oceans. Taharat Habayit v. 1 p. 407 agrees but adds if there is any linen stitching it is mekabel tumah.
  44. The Laws and Concepts of Niddah (pg. 46) by Rabbi Zvi Sobolofsky based on Taharat Habayit 8:11. Taharat Habayit is based on Rambam (Kelim 1:3) that one thread of mekabel tumah makes the entire clothing mekabel tumah. However, Shiurei Shevet Halevi p. 170 writes that as long as the majority of the clothing is made from material that isn't mekabel tumah the entire clothing isn't makebel tumah. Chok Uzman (ch. 2 fnt. 32 p. 106-107) quotes this from Rav Chaim Pinchas Sheinberg as well. Rav Pessin (Temurat Ayil 52) agreed. However, Chok Uzman explains that this approach only makes sense if the part that's mekabel tumah is mixed in completely with the part that's not mekabel tumah. However, if it is sewn together and the part that has material which is mekabel is recognizable, then everyone agrees it is mekabel tumah. His example is nylon tights with a cotton lining is mekabel tumah according to everyone. He explains that this lenient approach is based on the Mishna Lmelech.
  45. Minchat Yitzchak 4:118 holds that even nylon is mekabel tumah once it is made into an article of clothing. Badei Hashulchan 190:107 agrees.
  46. The Gemara Niddah 61b cites a machloket Rabbi Natan and Rabbanan whether colored garments have ketamim. Rashi (Niddah 61b) explains that there are no ketamim on colored garments since the blood isn't apparent on a colored garment. Taharat Habayit v. 1 p. 393 adds that in the days of chazal they would distinguish between different shades of red and so if the garment was colored that significantly change the ruling. Shulchan Aruch YD 190:10 holds like those rishonim who pasken that colored garments don't have ketamim. The Be'er Moshe 4:65 writes that a ketem on a colored garment that we know looks like blood is tameh. However, Taharat Habayit v. 1 p. 393 argues.
  47. Shevet Halevi YD 1:87 is strict regarding ketamim on yellow or other very light colored garments. However, Meil Tzedaka p. 62 and Rav Ovadia Yosef in Taharat Habayit v. 1 p. 387 disagree and holds that any colored garment doesn't have ketamim, even yellow. Rabbi Mordechai Willig (Niddah Shiur 91) and Rabbi Zvi Sobolofsky (Laws and Concepts of Niddah pg. 48) agree. The Laws of Niddah v. 1 p. 205 writes that if it is off-white certainly it is considered white (as white garments of the days of chazal were probably not as white as those of today). Yet, extremely light pastel colors are difficult to classify and a woman should avoid wearing them.
  48. Pitchei Teshuva 190:21 quotes the Chatam Sofer YD 161 that colored garments only prevent ketamim on the outer garments and not the undergarments. He is also concerned for those rishonim including the Hagahot Maimoniyot and Ramban who hold that a ketem on a colored garments renders the woman tameh to her husband, even though for taharot it doesn't. Nishmat Avraham 190:2 quotes that Rav Shlomo Zalman Auerbach was machmir for this. However, the Maharsham 1:81, Chazon Ish YD 89:4, and Chacham Ovadia Yosef (Taharat Habayit v. 1 p. 389, Shu"t Yabea Omer YD 3:3), Rav Zvi Sobolofsky (Laws and Concepts of Niddah pg. 48), Shoshanat Ha'amakim 1:12 are lenient.
  49. Pitchei Teshuva 190:20 quoting the Meil Tzedaka, The Laws of Niddah v. 1 p. 205, Taharat Habayit v. 1 p. 394, Shoshanat Ha'amakim 1:14
  50. Shoshanat Ha'amakim 1:13
  51. Rambam Isurei Biah 9:7, Rama 190:10, Shoshanat Ha'amakim 1:12, Taharat Habayit 1:8:6
    • Badei Hashulchan 190:117 writes that some rabbis recommend wearing colors even during 7 nekiim if the woman has serious staining problems
  52. Shulchan Aruch YD 190:11, Taharat Habayit 1:8:13, Shoshanat Ha'amakim 1:19. Shach 190:17 accepts Shulchan Aruch's assertion regarding toes that a ketem found on any of them makes her tameh while the Taz 190:11 is lenient if the ketem is found on the top of the foot beyond the toes further out than the area parallel to the big toe.
  53. Shulchan Aruch YD 190:11 based on Mishna Niddah 58b, Gemara Niddah 58b, Rashba, and Rambam. Shach 190:23 however, writes that we do not attribute to any outside sources during the first 3 days of shiva nekiim.
  54. Shulchan Aruch YD 190:11
  55. Shulchan Aruch YD 190:12 based on Gemara Niddah 57b, Rashba and Raavad. Shoshanat Ha'amakim 1:16 agrees.
  56. Shoshanat Ha'amakim 1:16
  57. Shulchan Aruch YD 190:14, Shoshanat Ha'amakim 1:17
  58. Shulchan Aruch YD 190:13, Shoshanat Ha'amakim 1:16
  59. Shulchan Aruch YD 190:39
  60. Taharat Habayit v. 1 p. 446, Badei Hashulchan 190:354, Shoshanat Ha'amakim 1:15
  61. Shulchan Aruch YD 190:1 rules that if a woman sees a ketem that is tameh she requires a hefsek tahara and needs to have seven clean days afterwards. Rama adds that we treat the ketem like her seeing her regular period for all intents and purposes. Additionally, the Rama 197:11 writes that after seeing a ketem a woman needs to wait 5 days. While the Shach 196:21 questions whether it is necessary to wait these days prior to shiva nekiyim if they didn't have tashmish within the last 4 days, he concludes by quoting the Levush who says that the minhag is to be strict like the Rama.
  62. Shulchan Aruch 190:54 quoting the Raavad states that becoming tameh as a result of a ketem doesn't form a veset.
  63. Badei Hashulchan 190:505. See Badei Hashulchan 190:506 that the same is true of the other vestot.
  64. Badei Hashulchan 190:505