Seed coat fragments (SCF) are extremely difficult contaminants to remove from cotton fibers because of the fibers attached to them. Literature data suggest that carding is the most effective cleaning step during which a significant proportion of the SCF is eliminated. In the study described here, different detection methods are used to evaluate the ability of carding to clean SCF-contaminated cottons. Variations in SCF number and size distribution are evaluated. The amount of fibers attached to the SCF is measured by image analysis, and it appears to have a significant effect on the ability of the card to remove SCF.