I agree the term fibre bundle has crept into the text, but I guess it is difficult to distinguish if you can see one fibre or a bundle of fibres under PLM. If the analyst doesn’t find fibres or bundles macroscopically after 10 minutes of searching, but fibres/bundles are found microscopically, then reporting ‘trace’ content would be appropriate. Using microchemistry might help with identification, where fibres could be hiding in a sample, very useful technique.
