I've noticed that coffee filters are getting hard to find lately at my local store for my Behmor BraZen which takes the 10 cup basket coffee filters. Several weeks ago I sent a bunch of Chemex filters to a friend who was running out and couldn't find any locally or online. I haven't started reusing the paper filters yet, I may just switch to my metal filters instead if I finally run out even though I prefer the taste with the paper filters.

My Wife told me that she had used a couple of my coffee filters in her cloth mask, even thought I sourced better filter material for this purpose.

I wonder if used filters (for pour over) are good for masks? I wouldn't suggest using it for a mask filter first then for coffee but I if you're the only one consuming it then I guess it doesn't matter.

You can order Lab filters too, they are always available and come with different porosity so you can choose the grade you want. They are flat and round so you have to shape it yourself but you can make a fluted design with a few simple folds. Cost wise should be as cheap as other filters

DamianWarS wrote:I wonder if used filters (for pour over) are good for masks?

New coffee filters apparently do a pretty good job at filtering micron sized particles but they aren't recommended because the breathability is so poor. You'll end up breathing almost entirely around the sides of the mask. Used filters? Kind of stinky, I imagine, without improving breathability.

Two layers of finely woven cotton seems to be the best filtration/breathability compromise for inexpensive COVID-19 masks.

I feed my filters to the worms/compost. Is this a bad practice?

Composting filters is fine, but since I don't have worms anymore I pull them out so the compost breaks down faster in the bin.

jpender wrote:New coffee filters apparently do a pretty good job at filtering micron sized particles but they aren't recommended because the breathability is so poor. You'll end up breathing almost entirely around the sides of the mask. Used filters? Kind of stinky, I imagine, without improving breathability.

Two layers of finely woven cotton seems to be the best filtration/breathability compromise for inexpensive COVID-19 masks.

depends the regulation. where I live the requirement is 2 layers but there is no requirement as to what those layers are. coffee filters would be acceptable but so would to pieces of cloth.

I'm not talking about regulation.

There have recently been studies of filtration efficiency and breathability of various fabrics and combinations. Two layers of finely woven cotton doesn't result in the very best mask but it's one of the best that uses materials that are inexpensive and easily obtainable. Most people already own fabric that is suitable.

A coffee filter would end up being less effective because you'd breath around it more than through it. Or so I've read. You could google all of these studies for yourself.

Or just try it. It's easy to make a mask.

I wonder if it would work to sew used coffee filters together to make clothing. Or at least a hat. Failing that, perhaps the larger size filters could be used as toilet paper. I suspect used Aeropress filters wouldn't work as well.

That'd be like asking for a clogged toilet

jpender wrote:I wonder if it would work to sew used coffee filters together to make clothing. Or at least a hat. Failing that, perhaps the larger size filters could be used as toilet paper. I suspect used Aeropress filters wouldn't work as well.

clothing yes, tp no. filters are pretty resilient and they won't flush well, and I certainly don't want to filter anything down there. I've heard they work good as cat hats.