Variations of this idea are genuienly vital health/survival info, right now, and will continue to be going forward.

Yes, one particular design may or may not be more effective than the other, but the basic concept of ‘duct tape a HEPA filter onto a box fan’ is absolutely a critical life hack to know if you live near anywhere that does or can experience signifcantly degraded air quality.

It isn’t perfect, but it immensely better than doing nothing, and most importantly, it is not horrendously cost prohibitive (at least currently, jfc).

Walking around for 30 minutes in wildfire smoke is roughly equivalent to smoking a couple of packs of cigarrettes.

You probably do not want to be inhaling that shit all day long, for many days at a time, if you live in a home/building that does not have its own air purification system.

Chances are you probably don’t.

So have these things on hand, to assemble, when a wildfire or something decides your city is especially beautiful to it.

Fires and smoke can come fast, suddenly, with relatively little warning.

Be prepared.