4 ms·

Not all cloth masks function the same way. If you read the studies, it depends on the weaving and the material. Cotton vs. denim, for example, is studied. None

by davmar 5y ago

Not all cloth masks function the same way. If you read the studies, it depends on the weaving and the material. Cotton vs. denim, for example, is studied. None are as effective as a non-woven material. But they are still more effective than no mask. Edit: > asbestos dust or second hand smoke You have to know what size of particulate matter that you're looking to filter is in order to determine whether that mask material works for the given application. What you're saying is too broad to be useful and isn't very insightful.

zdragnar 5y ago
Aerosol viral loads are (if I heard correctly) 50x smaller than asbestos particles. OSHA doesn't allow cloth masks to be used around asbestos. If this were a flu that spread primarily as droplets, cloth masks would have their place. As it is, we have known since early on that wasn't the case, and that cloth masks are about as useful as a cloth bonnet would be useful as a motorcycle helmet.
- davmar 5y ago
  https://pubs.acs.org/doi/10.1021/acsnano.0c05025 https://pubs.acs.org/doi/10.1021/acsnano.0c05025 "Materials were microimaged and tested against size selected NaCl aerosol with particle mobility diameters between 50 and 825 nm. Three of the top five best performing samples were woven 100% cotton with high to moderate yarn counts, and the other two were woven synthetics of moderate yarn counts" This image in particular: https://pubs.acs.org/na101/home/literatum/publisher/achs/journals/content/ancac3/2020/ancac3.2020.14.issue-7/acsnano.0c05025/20201113/images/medium/nn0c05025_0002.gif https://pubs.acs.org/na101/home/literatum/publisher/achs/jou... You can see N95 non-woven performs the best, but cotton twill does provide protection. Cool analogy tho.
  - zdragnar 5y ago
    50-850nm is way off; coronavirus are 20-500 tops. I guess we should call OSHA and tell them that it is okay to consider cloth masks as safety equipment around asbestos.

by davmar 5y ago

zdragnar 5y ago

Aerosol viral loads are (if I heard correctly) 50x smaller than asbestos particles. OSHA doesn't allow cloth masks to be used around asbestos. If this were a flu that spread primarily as droplets, cloth masks would have their place. As it is, we have known since early on that wasn't the case, and that cloth masks are about as useful as a cloth bonnet would be useful as a motorcycle helmet.

davmar 5y ago
https://pubs.acs.org/doi/10.1021/acsnano.0c05025 https://pubs.acs.org/doi/10.1021/acsnano.0c05025 "Materials were microimaged and tested against size selected NaCl aerosol with particle mobility diameters between 50 and 825 nm. Three of the top five best performing samples were woven 100% cotton with high to moderate yarn counts, and the other two were woven synthetics of moderate yarn counts" This image in particular: https://pubs.acs.org/na101/home/literatum/publisher/achs/journals/content/ancac3/2020/ancac3.2020.14.issue-7/acsnano.0c05025/20201113/images/medium/nn0c05025_0002.gif https://pubs.acs.org/na101/home/literatum/publisher/achs/jou... You can see N95 non-woven performs the best, but cotton twill does provide protection. Cool analogy tho.
- zdragnar 5y ago
  50-850nm is way off; coronavirus are 20-500 tops. I guess we should call OSHA and tell them that it is okay to consider cloth masks as safety equipment around asbestos.