New Variable Test Method For Home And Contract Floor Coverings

Textile floor coverings are classified into areas of application by mechanically producing changes in the appearance of samples in the laboratory. However, there is no test method for producing changes in the appearance of rigid textile floor coverings and thus simulating wear behaviour in practice. A new variable test method is likely to change this situation permanently. A change in the associated EU and DIN standards is also being discussed.

Normally, these tests/classifications use the subjectively assessed strength of the change in appearance to decide whether the floor coverings are suitable for home or contract use, for weak or heavy-duty. For this procedure, samples are fixed in a drum wall. However, the procedure has not been adapted for a long time – the last adjustment from practical stress to a simulation in the laboratory was carried out in 1984 in a research project of the TFI – Institute for Floor Systems at the RWTH Aachen University. Since then, however, the product range for floor coverings has been completely renewed.

With broad support from the flooring industry in Belgium and Germany, a variable test method – the so-called FOCuS method – has now been developed. It also enables the testing and classification of non-textile floor coverings. Up-to-date knowledge of movement mechanisms and forces of the human gait play a decisive role in this.

A New Test Method According To DIN And EU Standards?

For the new development, more than 30 textile floor coverings were provided by the participating companies, representing the current manufacturing spectrum in Europe. The test method that is most comparable to the human gait is the LissonTretradprüfung. However, this test is unsuitable for the subjective visual assessment of the change in appearance, as the assessable area is too small for the often coarsely structured and patterned floor coverings.

The current approach to the newly installed test tracks differs in essential conditions from the conventionally used methods such as frequency of use, lighting and dirt ingress. In addition to regular maintenance cleaning, not only were subjective assessments and colour measurements carried out on a regular basis, but also the state of wear was documented by scanning.

For the development of the new test method, various concepts were developed on the basis of the method review and human gait, and the current parameters of the “FOCuS” test method were worked out. In addition to the rubber stoppers of the “Vettermann drum test” and the soles of the treadmill test, metal abrasion bodies were used as wear bodies due to their better wear properties. The type of changes in appearance achieved with this method is comparable to the results in the hexapod test and in practice.

In addition, the results of the new test method were discussed in workshops with the members of the project-accompanying committee.  Overall, the new test method was considered to be very forward-looking. The findings gained during the project period in comparison to previous practice should therefore also be discussed in the relevant standardisation committees at German and European level.

A report on this topic was published in the 2/2019 edition of melliand Textilberichte, the authors were

• Sophia Gelderblom, Bayram Aslan; TFI – Institute for Soil Systems at RWTH Aachen University, Aachen
• Jo Wynendaele; Centexbel, Gent/Belgium
• Thorsten Knierim, Testing and Research Institute Pirmasens e.V. (PFI), Pirmasens
• Didier Van Daele; Ghent University, Ghent/Belgium