Post #854: Now will you take this seriously?

On September 12, 2020, I suggested that a box fan, some duct tape, and a 3M Filtrete ™ air filter was the best and cheapest approach to safe indoor dining in the COVID-19 era.  That’s Post #810.

I am not alone in figuring out that an air-curtain approach is the best possible method for separating individuals, once we all acknowledge that aerosol transmission is possible.

I’ve already voted, so I’m not tracking the debates.  But my wife thought it was worth quoting the NY times in this regard.  Because the fan-filter-duct tape solution is now slowly entering common knowledge.

"'A box fan, an air filter — and duct tape to attach them.

With four such cobbled together devices, at perhaps a total of $150, the vice-presidential debate on Wednesday night could be made much safer, according to experts in airborne viruses."
"Dr. Milton and his colleagues have contacted the debate commission, as well as both campaigns, to recommend purchasing plug-and-play air filters — excellent models cost just $300 each — or four box fans and air filters taped together. Each debater would have one device positioned to suck up and clean the air exhaled, and another to produce clean air.

In research conducted with singers over the past few months, Jelena Srebric, a mechanical engineer at the University of Maryland, found that this so-called Corsi box — named for Richard Corsi, an air quality expert at Portland State University — can significantly decrease the number of aerosols."

We will eventually figure this out.  Apollo 13 came home on the basis of duct tape and quick thinking.  America will eventually get through this crisis.  In part, perhaps, on the same basis.


Post #807: A vastly simpler mask liner using Filtrete ™

Source for base data: 3M, ASHRAE.  See Post #593 for writeup of these and other filtration standards.

I’ve done several posts about making masks out of Filtrete ™ home air-filter material.  Each time I return to that task, I find simpler ways to work with Filtrete ™.

In this post, I’m going to show just how easy it is to take a Filtrete ™ home air filter and make some simple, flat, easy-to-handle, fiber-free pieces for use inside cloth masks.  In a nutshell, extract the Filtrete ™ fabric from the air filter and hot-glue it between two layers of the thinnest synthetic fabric you can find.

Then end-user can then cut it to size, for use as a liner for a cloth mask.  That seems to work just fine, and nothing more labor-intensive is needed.  The materials run well under $0.25 per mask liner, depending on what size filter you buy, and how large you cut your mask liners.

A few tips and tricks for doing that are given below.  Of which, the only one that might not occur to you is to use kitchen “parchment paper” as a non-stick surface as you are gluing.

Continue reading Post #807: A vastly simpler mask liner using Filtrete ™

Post #780: Making an aerosol-filtering respirator from a dust mask and Filtrete (r) 1900

This post shows one way to upgrade a common dust mask so that it filters aerosol-sized particles.  The basic idea is not exactly rocket science:  Cover it with something that filters aerosol-sized particles. Continue reading Post #780: Making an aerosol-filtering respirator from a dust mask and Filtrete (r) 1900