Things You Didn’t Know You Needed to Know About Lint-Free Wipes

A recent search on Google for the term lint-free wipe returned over 18 million results. A further refinement to “lint-free wipes” returned over 330,000 results. And another search for “lint free wiper” produced over 1.5 million results. A simple change in characters or adding a letter churned out different results. The one thing they have in common, however, is a misnomer.

The truth is that there is no such item as a “lint-free wipe” because no material is entirely lint-free.

So, with all the lint-free results, how can this be? It’s because lint is a catch-all term referring to the short, fine fibers that separate from the surface of the cloth or yarn. It’s essential to note that the most crucial component of lint-free wipes is textile fibers – a material that is typically manufactured from natural or synthetic sources.

Dry Testing

When specialty wipers were first developed for cleanroom use, measurement techniques needed to be better developed. In the early 1980s, air particle measurement techniques were developed for testing wipers – so-called “dry testing.”  These measurements, which involved flexing the wipers mechanically, showed few releasable particles and fibers emerging from the wipers. Similarly, some wipers left few visible particles or fibers on the wiped surface. Hence the term “lint-free.”

Wet Testing

In the mid-1980s, all that changed when wipers were immersed in water or a dilute surfactant solution and gently agitated for a short time – so-called “wet testing.”  When the solution (in contact with the wipers) was passed through liquid particle measurement instruments or membrane filters, and the filters were examined microscopically, suddenly, significant particles and fibers were visible. The particles and fibers that adhered to the wiper when it was dry were released into the liquid and became available for detection and quantitation. It became clear that even the highest quality cleanroom wiper contained some particles and fibers, the components of lint. Interestingly, the most recent publication (2019) on wiper testing issued by the Institute for Environmental Science and Technology includes wet testing but not dry testing. Refer to IEST-RP- CC004.4 (2019), Section 7, for examples of acceptable testing for Particulate and Fiber contamination. Wet testing “sees” the particles and fibers that dry testing misses, providing greater measurement reproducibility.

Unfortunately, the “lint-free” adjective was never scrubbed from the cleanroom lexicon, and it has become an industry term synonymous with achieving the lowest levels of lint. However, no textile is entirely lint-free.

At Berkshire, we can scientifically measure the amount of lint contained in the wipe and provide the lowest level of lint-free wipes to suit the most stringent applications. Choosing the perfect lint-free wipe is based on factors such as your industry, application, and “total cost in use.” But often, the personal assessment of your cleanroom personnel on what works best is a good rule of thumb in the evaluation process.

So, what makes lint-free wipers a popular choice? Good question. The short answer is that they help keep cleanroom environments free of contaminants. The wiper’s ability to perform many tasks aids in maintaining the desired level of cleanliness in the cleanroom. That’s why choosing the proper type of cleanroom wiper is essential, especially when wiping hard surfaces and applying cleaning solutions is involved. So, how do you distinguish between similar cleanroom wipers when choosing the best wiper to suit your needs? The manufacturer’s product information sheet is an ideal place to begin. These sheets contain pertinent data that allows the end user to compare test results across several criteria. It serves as a precursor to other evaluation techniques, such as third-party testing, which is necessary to evaluate the cleanliness of a specific wiper product.

With a diverse range of lint-free cleanroom wipers, Berkshire is here to help you find the right wipe solution for your cleanroom need. Click here to learn more about our lint free cleanroom wipes. Need help to figure out what you need? Then reach out to our Technical Account Managers, who are well-trained and knowledgeable about contamination control and cleanroom supplies and ready to help guide you in your product selection.

Updated 6/8/2023