When Must I Check for Shatnez?

In previous articles, I discussed many of the basic laws of shatnez. We learned at the time that the prohibition of shatnez exists only if the garment is made from a blend of sheep’s wool and linen, but that wool of other species does not make shatnez. Thus, wool made of camel, rabbit or goat hair mixed with linen is not shatnez (Mishnah, Kilayim 9:1; see Rambam, Hilchos Kilayim 10:2). (“Wool” means simply soft hair that is comfortable enough to use as cloth.) Therefore since mohair and cashmere are both varieties of goat’s wool and not made from sheep’s wool, the existence of linen in a garment containing them will not make it shatnez. At the time, a correspondent noted that in practice one should not rely on this, since manufacturers usually add less expensive sheep’s wool to mohair and cashmere.

We also learned in the earlier articles that when a thread is spun from a blend of fibers, the halachic status of the thread is determined by what composes most of the thread’s content and ignores the existence of other fibers inside the thread (Mishnah Kilayim 9:1). Therefore, a thread spun from goat hair fiber with a small amount of sheep’s wool fiber cannot become shatnez, whereas a thread spun with a majority of sheep’s wool fiber can. However, a thread of linen that is woven into or otherwise attached to a woolen garment renders the garment shatnez, and there is no bitul (Rosh, Hilchos Kilei Begadim #5 quoting Tosefta; Shulchan Aruch, Yoreh Deah 299:1). Even a single linen thread in a large woolen garment renders the entire garment shatnez.

How should one check for shatnez?

The first step in checking for shatnez is to read the label when looking at the garment. Although one cannot be certain from this that the garment is not shatnez, it may tell you that it is.

Years ago, I was present when a frum organization conducted a men’s fashion show as a fundraiser. A local mechaneich was modeling a suit for the show when the announcer read the garment description over the microphone for all to hear: “This suit contains 70% wool and 30% linen.” I will not describe the pandemonium that ensued.

Here is another example:

Following a lecture on shatnez, a woman came forward with a scarf for which the content label stated: 48% Linen 42% Wool 10% Cashmere.

However, one should never rely on labels, which are notoriously inaccurate. Here is an example: =

May one rely on the label?

Since neither storekeepers nor manufacturers take any responsibility for the content label on their garments, I see no halachic basis to rely on them. The concepts of uman lo marei umnaso, that an expert may be relied upon because he is careful and concerned not to damage his professional reputation, and mirtas, that a merchant is concerned about being caught lying because it will affect his business, are true only when being caught with a lie or an error that will disparage their professional reputation. In an environment where we see that clothing stores feel no responsibility, legally or commercially, for the accuracy of the content labels on the clothes that they sell, there is no halachic basis to rely on those labels.

Even when a label is accurate, it describes only the material itself, but not backings, linings, ornaments, loops, fillings, button thread, etc., all of which often contain shatnez. It is even common that garments contain remnants of wool or linen thread in seams and canvasses that accomplish no recognizable purpose. For example, a number of shatnez laboratories have reported woolen sweaters containing remnants of linen threads in their seams.

Here is another example: A sweater purchased in a store in Boro Park, was labeled as 70% acrylic and 30% wool. This appears to have correctly described the exterior of the sweater, but no mention was made of the materials’ of the lining – which was 100% linen – making it shatnez min haTorah.

So how does one know whether a garment must be checked for shatnez?

Although all types of garments might contain shatnez, the halachic question is: When is the possibility of shatnez frequent enough to require that this garment be checked.

The laws of checking are not unique to shatnez. Let us see if we can compare shatnez to other halachic issues. The most extensive discussion about checking for non-kosher items regards checking animals to see if they are tereifos, defects that render them non-kosher. This halacha is germane to all meat, eggs and dairy products that we consume, since the eggs produced by a tereifah chicken and milk from a tereifah cow are also non-kosher. So what can we do? If we were to check every chicken or cow for tereifos before we consumed any eggs or dairy products, this would drive up the price of eggs and milk considerably, since we would need to slaughter the chicken before we could consume its egg and the cow before we could drink its milk. Obviously, we all realize that halacha does not require this. So what does halacha require?

The general rule regarding checking these items is as follows:

When a problem exists in more than half of a species, one may not consume the product of that species without checking. When one cannot easily check for a problem, and it occurs less than half the time, there is no need to check for a problem, One may eat eggs or drink milk and rely that the majority of chickens and cows are not tereifah.

Regarding meat, the halachic authorities dispute when one is required to check for tereifos. How high a percentage of tereifos is needed to require examination? A dispute over this issue developed in the early nineteenth century between two great poskim, Rav Efrayim Zalman Margolies, the Rav of Brody (Shu”t Beis Efrayim, Yoreh Deah #6) and Rav Yaakov of Karlin (Shu”t Mishkenos Yaakov, Yoreh Deah #16 & 17). The Beis Efrayim contended that it is not necessary to check for a tereifah if we do not find that Chazal and early poskim required it, whereas the Mishkenos Yaakov contended that if a certain tereifah occurs in ten per cent of animals, one is required to check every animal for this tereifah. (The halachic source for this figure of ten per cent is beyond the scope of this article.) It appears that the accepted approach today is to follow the Mishkenos Yaakov’s ruling and check for tereifos that appear frequently (see Darkei Teshuvah 39:3), although some contemporary authorities feel that the percentage should be closer to seven per cent than ten per cent. This percentage is usually called mi’ut hamatzuy, literally, a commonly found minority.

Do we compare tereifos to shatnez?

Do we do a statistical survey of shatnez found in clothing and see if we find shatnez in 10% of men’s suits, ladies’ sweaters, etc.?

The halachic sources do not imply this. Based on a Mishnah (Kilayim 9:7), the Rambam rules “Someone who purchases wool garments must have them checked very well to determine that they are not sewn with linen thread” (Rambam, Hilchos Kilayim 9:28). He does not say that it depends on the percentage of shatnez that we find.

For example, one early authority contends that whether we need to be concerned about shatnez depends on local market conditions (Rash, Kilayim 9:7). When hemp is readily available and less expensive than linen, one need not be concerned that a tailor would use linen (see also Taz, Yoreh Deah 302:4). The Shulchan Aruch (Yoreh Deah 302:2) concludes the following: “One purchasing wool garments from a gentile must remove all the stitching and replace them with hemp,” although he also rules like the Rash that one may be lenient when hemp is readily available and less expensive than linen. (We should note that there are authorities who disagree with the Rash and the Shulchan Aruch, contending that one may not be lenient even when hemp is readily available and less expensive than linen, because the tailor may prefer working with linen, which is stronger and easier to work than hemp.)

It appears that we do not use the rules of mi’ut hamatzuy – that we statistically use 10% to determine whether we must check, for the laws of shatnez – for the following reason. All the cases of mi’ut hamatzuy are when there is a natural situation that something happens – wine sours, animals develop diseases or injuries that render them tereifah, or insects dine on vegetables. One cannot apply mi’ut hamatzuy to something dependent on the whim of a manufacturer, who is, after all, a baal bechirah. Thus, we should compare the laws of shatnez to situations where we are concerned about whether a product was adulterated with a non-kosher substitute. There the logic is: Do we suspect that someone would adulterate the product with non-kosher? The answer is that we must be strict when we suspect that there might be a problem, and we are not required to be strict when there is no reason for suspicion. The same rules apply to shatnez.

With this background, we can understand that any garment that has a reasonable concern that there might be shatnez needs to be checked.

Cannot check in time

What if I cannot get it checked in time, and I need to wear it immediately? Reuvein arrives in Zurich the day that his brother is getting married, but his suitcase did not end up on his flight. He has nothing appropriate to wear to the wedding, and there is no time to have a new suit checked for shatnez. May he purchase a suit and wear it to the wedding, and only afterwards have it checked for shatnez?

My suggestion is that he call a local shatnez tester or one of the major shatnez testing laboratories, as they may be able to advise which brands have a lesser chance of being shatnez, or they may know that a particular brand is mostly shatnez and it would be assur to wear that brand without checking.

Here is an actual story. The night of bedikas chometz, about 6 years ago, a yeshiva man called the Har Nof Shatnez lab. He purchased a new suit in Geula and wanted a “heter” to wear it on Pesach, relying that “most suits in Geula” are probably not shatnez. Although the particular brand had been shatnez-free in previous years, the shatnez checker knew that 700 suits containing shatnez of that brand were recently brought into Israel and some had been distributed to local “frum” stores. Based on this information, the “checker” told the consumer to do bedikas chometz and then bring the suit for checking. The suit’s collar indeed contained shatnez, which was removed that night, and the suit was tailored the following morning. BH – he didn’t wear shatnez at his Pesach seder!