The lonely shatnez tester using the batterie d'badika shown above works to save us from a serious averra...the wearing of a garment which contains a combination of sheep or lamb's wool and linen.  We tend to think it's something found only in men's suits, but it can and often is found in women's, children's, and even home furnishings such as rugs and carpets.  For a comprehensive portal go to Shatnez Lab of Houston.


The word "shatnez" is actually a truncated combination of "shua" (combed), "tovi" (spun), and "nuz" (woven).  The applicable halachas are few but complex.  In short we have an obligation to check, particularly if we have a garment which we know to be wool or linen.  If you think "100% wool" on the product label means what it says, think again.  If you think the guy in Boro Park selling you a suit which he claims is 100% shatnez free is, think again.  Shatnez shows up in the the most expensive and the cheapest garments.  It's there where you least expect it.

Burning in an alcohol flame used to be the test of choice: wool and hair smell, linen flames, and synthetics often melt.  Now we rely on the microscope which definitively distinguishes one fiber from another:  the bamboo-like nodes in linen...

A typical suit has 35 - 50 places which require examination to determine if shatnez is present.  Sometimes you can tell just by looking; sometimes by pulling apart a thread and observing the nature of the fibers; and sometimes the fibers have to be examined under a microscope.

The shatnez tester does not need to tear irredeemably apart the garment to check the suspect areas, but he must open up small seams in a few places to turn it inside out. For all practical purposes shatnez testing is essentially non-destructive.

Shatnez testers usually charge small, nominal fees for a service that may take up to an hour to perform.   Find out who they are in your town, and bring your garments in for checking in plenty of time.  Erev yuntiff is already too late.