Cotton Contamination & Colour Grade Risk Scorer

The weights here are a stated convention, not a measurement: polypropylene is weighted an order of magnitude above the graded defects because its failure mode is categorical rather than proportional — it does not make the yarn slightly worse, it makes one finished piece unsellable, and it is detected after every value-adding process has already been paid for. That is why the polypropylene share is printed separately and why a lot with any PP at all should be stopped and hand-sorted whatever the composite says. Stickiness behaves differently again: it is a processing failure, not an appearance defect, and honeydew contamination that passes a visual inspection can still shut a spinning frame down through roller lapping in humid weather, so read the SCT count against your own mill humidity rather than against a trade limit. Counts depend entirely on sample size and inspector diligence — an untrained inspection reliably returns zero.