4 ms·
To be effective a filter has to be a restriction, how are they showing people with increased performance with a filter? Unless the filters aren’t working.....
by thedrbrian 6y ago
To be effective a filter has to be a restriction, how are they showing people with increased performance with a filter?
Unless the filters aren’t working.....
- jfengel 6y agoThe filter is intended to filter out particles 100 nanometers and up. Air molecules are .3 nanometers. So a mask can, in fact, both filter out the disease vectors while allowing oxygen in and CO2 out.