Cloth Face Coverings [Masks] provide a physical barrier that reduces the transfer of airborne droplets which cause respiratory infections. A face coverings can be constructed with or without a sewing machine. Appropriate fabrics, 3-4 layers and fit increase level the level of protection. A face covering/mask does not guarantee protection against the transmission of any disease.
https://extension.okstate.edu/coronavirus/media/home/diy-masks-english-covid-19.pdf
This series was created by Dr. Lynn Boorady and Dr. Sumit Mandal with Design, Housing, andMerchandising, and Karla Knoepfli with Oklahoma 4H and is as part of the OSU Extension effort in combating COVID-19.
You can find more information at the following websites:
https://www.cdc.gov/
https://extension.okstate.edu/coronavirus.html