The prohibition of shatnez is a prohibition of wearing or covering oneself in a beneficial way similar to wearing. A tent or umbrella made from shatnez would be permitted to use even if you are being protected from the elements.

Just as it is forbidden to feed your child treif food to eat it is also forbidden to dress a child in shatnez. There is no distinction between your child and someone else’s child. Therefore children’s clothing which may contain shatnez must be tested.

The Torah’s prohibition of shatnez primarily refers to wearing of shatnez garments. Sitting, lying, or walking on shatnez would be permitted. There is, however, a Rabbinic decree prohibiting these activities due to the fact that the shatnez material may rise up and cover part of the body. Therefore carpets, rugs, mattresses, pillows, couches and chairs could possibly be a concern if they contain shatnez. Regarding mats of mattresses the Talmud says even if ten mattresses lay one on top of the other, and the bottom one is Shatnez, it is forbidden to sit on the top mattress.

This rabbinic prohibition largely depends on the softness of materials used in the construction of the article in question. Soft materials are forbidden and firm materials are permitted. Due to the complexity of these details, it is advisable to consult a Rabbinical authority or your local certified shatnez laboratory whenever a question arises regarding the possibility of shatnez in these items.

May one try on a shatnez garment for size?
When one goes to a clothing store to buy a new suit, pants or dress is it permitted to try it on before having the article tested for shatnez?

Usually when people shop for clothing the shatnez status of the garment purchased is unknown. In this case it is permitted to try on the clothing in the store or in the privacy of one’s home to see if it fits. Even if it is known that these garments sometimes contain shatnez, it is still permitted to try them on, unless one knows that the particular garment he is trying on is shatnez.

In the less common case when you know the garment you want to try on for size is shatnez the halachic opinions vary. If a garment is known to contain shatnez, it is prohibited for those who follow the opinion of the Beis Yosef,(such as many of those of Sephardic descent), to try on the garment in order to buy it. If, however, one wishes to model the garment for another person, some authorities would permit it. Some would even permit the buyer to try on a shatnez garment, provided that he will not buy the garment he is trying on. Rather, he should try on another garment that is identical in size and style to the one he will buy.

For those who follow the opinion of the Rama, it would be permitted to try on a shatnez garment in the dressing room of the store or in the privacy of one’s home. It would also be permitted to try on a jacket or a coat in the store itself, since he does not benefit from wearing such a garment in such circumstances. Trying on trousers, or any other garment one would be embarrassed to be seen without, would be prohibited in the store outside the privacy of the dressing room.

Some are of the opinion that even those of Ashkenazic descent should not try on a shatnez garment. It would then be permitted only in the manner described above according to the Beis Yosef. The custom, however, is to be lenient like the Rama.

When a tailor or a shatnez tester is working on a garment, it is common for them to drape the garment across their lap as they work. This is permitted, since there is no intent to benefit from the warmth of the garment.

This being said it is strictly forbidden to wear a garment that requires shatnez testing, even temporally without having it first tested by a certified shatnez laboratory.

If you have questions regarding shatnez, you may write to Rabbi Neiman at [email protected]

Rabbi Eliyahu Neiman in 1991 was certified as expert in the field of shatnez in testing and halacha from the “Vaad Mishmeres Habeged” of Bnei Brak and the “International Association of Professional Shatnez Testers and Laboratories” of  Lakewood, NJ. 
Founded and managed the “Kiryat Sefer-Modi’in Illit Shatnez Laboratory from 1991-2005.
Senior tester in “Mishmeres Nasson Shatnez Laboratories Jerusalem from 2002-2008.
Rabbi Neiman is presently manager of the “Shatnez Express Betar Illit” as well as the “RBS (Ramat Beit Shemesh) Shatnez Laboratory”. He also runs Shatnez pick-ups in Jerusalem’s Ramat Eshkol, Yeshiva Ohr Somayach and N’vei Yaakov.

(Jerusalem Kosher News – www.jerusalemkoshernews.com)