I couldn't be bothered to buy the rubber thing but I am finding that a pair of rubber bands improves both my surgical masks and my K95s (which otherwise don't fit me well). Thanks for the tip!

Did you do any smell testing to see whether the mask fits in a way that makes you unable to smell things?

I live in NSW Australia and we are currently (3 Sep 2021) battling Delta strain, which has a Reff of 1.3 even during a strict lockdown, curfews, and a reasonably high vaccination rate.

It’s got to be the masks, right? People are going shopping, wearing whatever mask they have, and getting infected because someone infected with covid is in the store and also not properly masked. Medical workers in full PPE are getting infected - how leakproof are their masks, really?

Our Government should do some trials to find the best inexpensive masks or mask-brace combination for getting Reff below 1.0, and then just give everyone a box of them to be used when they need to go out during the lockdown. With Reff below 1.0 we would eliminate covid sooner or later, and would aim to keep it that way.

I was inspired by this article to solve my own leaky mask problem. I have a nice 3M respirator mask with two discrete filters that seals really well to my face but I haven’t been able to use it during the pandemic because it has an exhaust valve. It only took ten minutes to remove the little round valve flaps that stop exhaled air going through the filters, and to put duct tape over the inside of the central exhaled air valve.

I cannot reproduce your demonstration of electrostatic charge, even if I am using masks or respirators, which I believe not to be fake. Please, what are the particles ? Paper ? Cut paper napkins ? What are they laying on ?

Disclaimer: I'm not an expert.

It turns out that surgical masks are made of the exact same material as N95s! They both filter 95% of 0.1μm particles.

I very much doubt this claim, and the link you provide in support of it is to a website that you later suggest is being run by people that seem to you "a bit sketchy". I also doubt that the way you propose for checking the "electrostatic effect" (on large pieces of paper?) can provide strong evidence that the mask's material provides filtering protection that is similar to a N95 respirator.

[EDIT: sorry, you later cite the Rengasamy et al. paper that seems to support that claim to some extent; I'm not sure how much to update on it.]

As a civilian you can’t purchase an N95 anywhere at any price.

This claim is false (see this [EA(p) · GW(p)] thread).

BTW: since presumably surgical masks are not intended to be used in this way, I would also worry about potential risks of breathing too little oxygen or too much carbon dioxide.

BTW2: Maybe it's worth looking into using your approach for "upgrading" cheap KN95 respirators rather than surgical masks (I suspect that cheap KN95 respirators tend to not seal well due to a lack of nose clip and due to bands that go around the ears rather than around the head). Though the above concern regarding oxygen/carbon dioxide might still apply.

[EDIT: BTW3: for a comparison between cloth masks, surgical masks and N95 respirators see this page on examine.com.]