According to a research paper published by CDC, multiple layers of water resistant materials made cloth masks have been found to be effective in protecting against the coronavirus
Cloth masks have been used in healthcare and community settings to protect the wearer from respiratory infections. The use of cloth masks during the coronavirus disease (COVID-19) pandemic is under debate.
- The filtration effectiveness of cloth masks is generally lower than that of medical masks and respirators;...
https://mfame.guru/cloth-masks-made-of-water-resistant-material-effective-against-covid/