How long can the non-woven fabric be exposed to sunlight

Non-woven fabrics can be produced from different raw materials. The problem you ask is mainly for polypropylene (also known as PP) nonwovens, because this material will age under ultraviolet light and eventually become powder. It is worth mentioning that many shopping bags on the market are non-woven fabrics made of PP. If they are exposed to sunlight, they will age.