This part of ISO 5350 specifies a method for the estimation by transmitted light of the visible dirt and shives in laboratory sheets prepared from pulp. It is in principle applicable to all kinds of pulp, though it is mainly intended for pulp that is not manufactured in sheet form.
This part can also be applied to mill sheeted pulp if the sheets have high grammage or are very opaque for other reasons, in which case Part 2 is not applicable.
This International Standard is not intended for recycled pulp.
NOTE Shives in mechanical pulp are usually determined by means based on screening or optical analyses. Some grades of mechanical pulps can cause problems in sheet-making or inspection, which makes this International standard impractical.