Discolouration of the pages

As paper colour assessment is very subjective, change of paper colour on one sheet is assessed. For example sheet edges can be yellower in comparison with the rest of the sheet.

Damage categories

	Description	Pictures
Not selected	Discolouration is not identifiable
Not selected	Slight yellowness on single sheets (less than 10%).
Not selected	Severe yellowness on 10–30% of the sheets
Not selected	Very severe brownish yellow tone on more than 30% of the sheets.