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FAQs on Microfibers in the Fashion Industry

Learn from UL’s softline expert, Angela Donati, about the regulatory updates affecting microfibers in the fashion industry.


November 1, 2021

Following UL’s webinar, “Microfibers: Updates from Europe and the U.S.,” we interviewed Angela Donati, our softline technical expert, to clarify the most frequently asked questions from brands and retailers regarding microfibers, fiber loss during washing, and their environmental impact.

Please find the complete interview below. Contact us for further information.

Why is detergent not used in part 1 of the European proposed test method?

According to prEN ISO 4484-1, detergent has intentionally been left out of this test method and we do not recommend the use of detergent in this method. Detergent has been found to clog filters during the filtration process and sticks to fibres and filters during the whole testing procedure. This adds mass that can distort data and lead to misinterpretation of results.

According to ISO/CD 4484-3, a detergent may be used for washing tests and the preferable reference detergent is a nonphosphate liquid detergent.

According to AATCC 212 AATCC High Efficiency (HE) Standard, Reference Liquid Detergent WOB (without optical brightener) can be used. The test report must specify if testing was done using the detergent or water only.

Has any interlaboratory trial been organized to validate part 1 of the European proposed test method?

Yes, this interlaboratory trial involved 10 laboratories across six countries. Four samples were considered, and each laboratory tested 16 specimens for each sample. UL’s softline laboratory in Italy participated in this interlaboratory trial and, based on the good test results, we can be optimistic on the date of publication of this test method.

Which type of washing machine is used to test garments according to ISO/CD 4484-3?

Although there are many types of washing machines used at home, ISO developed the ISO 6330 domestic washing test method and included a description of the domestic washing machines and test conditions. According to ISO 6330, three different types of washing machines can be used:

  • Type A: Horizontal axis, frontloading type,
  • Type B: Vertical axis, top-loading agitator type
  • Type C: Vertical Axis, top-loading pulsator type

The type of washing machine used must be specified in the test report. Due to the complicated structure of the washing machine, cleaning of the washing machine is an important issue and ISO/CD 4484-3 proposes the verification of cleanliness.

How can UL help luxury brands and fashion retailers measure their environmental impact for fiber fragments?

First of all, as the regulatory landscape in this field is constantly evolving, we keep our customers updated on developments in technical standards and legislation. In addition, our laboratory network has the capability to test according to AATCC, The Microfiber Consortium standard and the draft prEN ISO 4484-1.