@flowermusickids @kprather88 @CDCgov Cotton+silk or cotton+chiffon is around 80% in this study, but requires care to ensure excellent fit. I bought some masks made like this from Etsy early on, but ended up switching to KF94 shortly thereafter.
https://pubs.acs.org/doi/10.10...
@在这项研究中，flowermusickids@kprather88@CDCgov Cotton+丝绸或Cotton+雪纺约占80%，但需要小心以确保完美贴合。我很早就从Etsy买了一些这样的口罩，但不久之后就换成了KF94。
https://pubs.acs.org/doi/10.10...