- Dr. Scott Segal, Wake Forest Baptist Health
While some of the masks studied at Wake Forest filtered as little as 1 percent of particulates, the best filtration masks were actually all-cotton, high thread count cloth masks OR certified N95 masks.
Knits, cotton blends, polyester blends, gaiters, bandanas, t-shirts, valve masks, scarves, single layers, open-weave fabrics, etc. provide little to no protection -- and might actually aerosolize and spread COVID-19. Sadly, businesses, hospitals and health insurers have fallen prey to ordering and distributing unsafe knit, synthetic or cotton-blend masks with company logos.
- - - - -
BASIC REQUIREMENTS FOR HIGH-FILTRATION (79% or higher) CLOTH MASKS:
- minimum of two layers
- each layer tightly woven "quilting weight" or "batik"
- 100 percent cotton
- optional 100% cotton flannel inner lining (middle layer)
- avoid seams, decorative sewing, punctures on mask front or "breathing zone"
If buying a pre-made cloth mask, make sure the lining (against the face) is not an inferior open-weave cotton, a prevalent trick used to hide inferior quality fabrics on the inside toward the face. (TRICK: Show an outer, heavy-weight layer in your packaging; Use a cheap, open-weave, bandana-weight cotton as your second layer.)
Since most people won't be sewing with silk, I've left out recommendations.