ISO 21915-1:2020

This document specifies the qualitative analysis for cupro and lyocell using the two methods separately:
-  scanning electron microscope (SEM) method based on the application of ISO 20705, and
-  spectral analysis method.
These testing methods are applied only for cupro and lyocell, or those blends. If other fibres are present, those are identified using the test method of ISO/TR 11827 and removed using the relevant part of the ISO 1833 series.
This method is not applicable for the fibre surface that is damaged during the process (e.g. chemically or physically).