a rational case against mask effectiveness

I've heard this argument in bits and pieces, but I've never seen it laid out quite like this (found in an Instapundit comment thread and slightly edited):

I work in the HVAC industry, so air filtration is something I have been dealing with for over 40 years, including air filtration for surgical suites, TB wards, and labs. And as technically complicated as that may sound, the principles behind it are almost absurdly simple: the holes in the filtering media have to be smaller than what it is that you want to filter out, while at the same time allowing adequate air flow.

So, given that the Covid virus is infinitely smaller than the micron rating (micron rating is the size of the smallest particle that a filter can trap) of even the N95 mask, masks are an exercise in futility. I have been saying this from the start, and the analogy that "using a mask to filter out Covid is like using a chain link fence to filter out mosquitoes" is totally apt. It was a simple way to describe the situation, so of course, the know-nothings in our legacy media had to denigrate it lest people start realizing what a crock of feces they were peddling. Consequently, there was more unadulterated complete and utter BS spread about masks than rational thought could sweep away.

First was the incomprehensible idea that all masks were equally effective at preventing the spread of Covid no matter what they were made of—a concept so bereft of any basis in science or engineering that adherence to it was more an article of faith that one would find in a religion than anything a rational thinker would believe. Then [the pro-maskers] trotted out the insane idea that masks with high micron ratings were still effective because the Covid virus rode on bits of moisture when transmitted by aerosol, and so moisture could be trapped more easily than the virus alone. Of course, this bit of nonsense was also bereft of any basis in science or engineering. While it is true that you could trap moisture more easily, any mask that did so effectively would soon accumulate so much moisture that the wearer would quickly be waterboarding himself with the moisture from his own breath. It also ignores the fact that if an unmasked person exhales his or her breath into the air, the moisture is almost instantaneously absorbed by the air as it has a far lower humidity level than a human's exhalations.

So the real way to combat these moronic mandates is to force those imposing them to defend them on a rational and scientific level, and they will not be able to do so.

I admit I'd bought in to the notion that a mask could at least stop droplets, e.g., when coughing and sneezing. I'd never thought of the angle provided in the above comment. If the Party of Science really wants to be the Party of Science, it should listen to people like the above commenter. Ultimately, the whole mask thing is a charade. One of several perpetrated on the people. And I say that as someone who has now been through COVID.