Just make sure it says Filtrete. No glass. Looks like the doctor didn't do his homework.
On Sat, Apr 4, 2020 at 7:17 PM Charles <fran...@datacomm.ch> wrote: > Maybe not such a good idea: https://www.youtube.com/watch?v=qiYbXsIcI7E > > On 05/04/2020 00:35, Terry Blanton wrote: > > I found an old Hoover HEPA vacuum bag and thought to make a mask. > > Then I Googled the idea. Nothing new under the sun. HEPA spec is 300 > > nm but test show them effective down to 50 nm (depends on the > > rating). SARS-CoV-2 is 125 nm. > > > > https://youtu.be/W6d3twpHwis > >
