USA Masks are made of non-woven fabric, at 20 to 25 grams per square meter in density. We use three layers of material, a melt-blown polymer (usually polycarbonate, polyethylene, polypropylene, polystyrene, or polyester). Masks that are used for dust protection and non-surgical masks can be made of cloth.
The outer layer repels water, blood, and other body fluids
The middle layer filters certain pathogens
The inner layer absorbs moisture and sweat from exhaled air