This document specifies three methods for the determination of the number of threads per centimetre in woven fabrics. Any of the three methods can be used, the choice depending on the character of the fabric. However, in case of dispute, method A takes precedence.
—Method A: Dissection of fabric, suitable for all fabrics. This is the most laborious method but has fewer limitations than the others; in particular, it is the only one that is really suitable for the examination of certain folded structures and other complicated weaves.
—Method B: Counting glass, suitable for fabrics with more than 50 threads per centimetre.
—Method C: Traversing thread counter, suitable for all fabrics.
Where the number of threads per centimetre is low, it can be convenient to express the results as the number of threads per decimetre.