Everything About Masks


  More Homemade Mask Details

  Donate Masks & Goggles

  Comparisons Of Mask Materials

  Mask Design Matters

  No Hepa Vacuum Bags

  N95 vs N95S Masks

  Vented Mask Dangers

  Request For Fabric

Some of these I’ve run before, but I thought I’d put everything in one place. Key sections are new. We now want everyone wearing masks in public. So we need lots more of them homemade. But design matters. It’s a bitter shame when healthcare workers throw away masks because they are unusable. Read “Design Matters” below for guidance. And please spread the word about exhalation valve dangers. Thank you! (Second post about everything else will follow.)


Please wear masks and bandanas in public! Testing is now showing that people are often contagious without symptoms, that people can be contagious a long time after symptoms resolve, and that simple masks and even bandanas offer significant protection, especially when used in combination with physical distancing and great hygiene measures. Homemade masks should fit snugly and be washed after each use. If reuse is needed masks can have a contrasting inside and outside fabric so you can be careful to not let the outside ever touch the inside of your mask or your face. Wash your hands before and after touching your mask and if possible only touch the ties, not the fabric.


Many neighbors have done Map Your Neighborhood on their blocks. Most groups that did, received at least one orange backpack with emergency supplies at that meeting. I had forgotten that among those supplies were one or two N95 masks and a pair of clear goggles that fit over a pair of glasses. Hospital workers really need both of those items right now. Ummm… really, really need them. Can you donate yours? Contact me to set it up. Even if your stash didn’t come from Map Your Neighborhood.


Making DIY Masks with Household Materials

Bottom line: Test data shows that the best choices for DIY masks are cotton t-shirts, pillowcases, or other cotton materials. These materials filter out approximately 50% of 0.2 micron particles, similar in size to the coronavirus. They are also as easy to breathe through as surgical masks, which makes them more comfortable, enough to wear for several hours. DOUBLING THE LAYERS OF MATERIAL FOR YOUR DIY MASK GIVES A VERY SMALL INCREASE IN FILTRATION EFFECTIVENESS, BUT MAKES THE MASK MUCH MORE DIFFICULT TO BREATHE THROUGH. (Paper towels are less than half as effective.) https://smartairfilters.com/en/blog/best-materials-make-diy-face-mask-virus/   


Bria Schurke

March 29 at 11:12 AM

Anything is NOT better than nothing, particularly if masks become vectors themselves. Design is just as important as fabric for DIY masks.

Hi all, I am a public health practitioner, medical provider, and my family has a large scale clothing production company. I am working with about 250 people making homemade masks for various organizations and hospitals that I am involved with. I am finding that MANY of the DIY donated masks DO NOT WORK and we are unfortunately having to throw them away. This is what I have learned so far and suggestions I have for people who want to mass produce DIY masks designed to reduce droplet distribution. Disclaimer: masks I am discussing are NOT designed to reduce inhalation of COVID-19, they only reduce droplet distribution by someone who has a cough.

I’d much prefer if we could all use medical grade N95 masks, but that is simply not a reality and we are forced to mass produce DIY masks as a community.

There is a lot of emphasis put on the fabric and materials used for the masks..and less emphasis on the design. Currently the Minnesota Department of Health has no recommendation for mask design, per recent guidelines issued yesterday.. As a medical provider, this is a huge concern.

Masks with elastic ear loops do not accommodate for different head sizes, the tend to fall off, and wearers tend to touch their face to readjust them. Ear loops also cause sore ears after hours of use. I watched my own triage nurse holding her DIY mask on her face as she swabbed COVID-19 patients. The mask would simply not stay on and we do not have any masks in our clinic or ER.  This is a problem then, if people are now touching their face more, then touching public counters, door knobs etc. The CDC recommends that symptomatic people wear the DIY 2 layer 100% cotton masks to reduce the spread of droplets. It seems like the fabric recommendations are changing daily and there is still ample research needed to be done on best practices for DIY home masks.

Cute masks with designs, thick/stiff fabric, are difficult to wash and difficult to breath in. Even if we use the correct recommended fabric, if the masks don’t fit well, are unbearable to wear for at least an hour, and can’t be washed easily, then they are pointless.  Also elastic breaks down in cleaning solutions and heat. Once elastic is stretched out it renders the mask useless.

If we really want effective masks that reduce the spread of droplets that are mass produced by the general public then I strongly recommend designing masks with these standards:

1) ties behind head (reduces face touching, stays on face). Ear loops are causing people ears to become sore and even bleed after hours of use.

2) Easy to wash (using light colored monotone or pure white fabric, ink bleeds when washed sometimes) *Edit: MDH guidelines now recommend washing in hot water and detergent after every use. This is IMPORTANT! Otherwise you just have another disease vector. COVID-19 “lives” in the mouth.

3) covers brim of nose to under chin and expands well across the face

4)accommodates different head sizes with same pattern size.

5)wearable for a long period of time (does not irritate face, somewhat breathable, stays on face)

6) meets CDC standards (2 layer 100% cotton) Seems to be changing daily!

7) accommodates shrinkage when washed

8) minimal materials and easy to make for mass production

9) uses a pattern that accommodates for different sewing skills. some masks do not fit at all if the cut or straight stitch is off.

10) uses straight cut for mass production and less waste of fabric (vs mask design with rounded edges that wastes fabric).

The time is now for Minnesota to prepare and get this right. People are putting a ton of effort into making masks to donate. It is a waste of their time, resources, and effort if they are making masks that either are intolerable to wear and/or become vectors for disease because they force people to touch their face more. I hate to keep throwing away donated masks because they simply do not cover the face well, fall off, or can’t be washed.

Everyone who makes DIY masks should fit test them for at least 5-10 min prior to making more..and ensure the recommendations listed above. Have someone with a different sized head try them on for a while too.

Attached is a design that is:

1)easily mass produced (cuts production by 1/3 from pleated design)

2)made with washable white fabric

3) ties behind the head, similar to masks we wear in surgery

4) accommodates a wide variety sewing skills

5) is secure, stays on the face and doesn’t need to be adjusted

6) can be worn for a long period of time.

This pattern is simple, reduces waste and only uses 2 10″ x 8″ pieces of 100% cotton (straight up rectangle, no rounded edges!) and 2 38″ strips of twill tape (can also use shoelace material or whatever material will tie securely, but can also be untied). Designed to be worn by the general public and not necessarily as a cover over an N95 (but can also be used for a cover as well.)

Here is a link to a google drive with instruction video and pattern:


I’d love to continue brainstorming with folks. I have been working on prototypes and fit testing many different designs and fabrics for the last 3 weeks. I really believe we need to get this right and make sure the public is well informed. Design truly matters!!!(Design from Good Clothing Company, not my own.)


A quick warning : Do not use HEPA rated vacuum bags if you are making masks from vacuum cleaner bags. I searched a lot of sites to find any issues and I found two sites that warn that the HEPA rated vacuum bags are made with glass fibers and some are sprayed with chemicals. This is not the case for the paper and cloth bags of the kind we are using. While they do not filter as tightly as the HEPA specification, they are adequate for most uses except front line medical workers who need m95 or m99 masks. So don’t try to improve them by using HEPA bags. Interestingly, I stumbled across a site that was actually warning about the contents found in used vacuum bags. Of course do not make masks from used bags. They must be new and clean and not HEPA. ~Paul Eisenberg


From my big brother: Flip, do not use N95s as a plural form. Use “N95 masks.” It confuses the issue in a very serious way. In fact, go through your posts and make sure you have not used N95S as a plural and if you have, replace it. [Done.]

  N95s is a designation for masks that are intended and allowed to be used in sterile fields, masks that are treated with antimicrobials and hydrophobic surface treatments.

   An N95S is a completely different animal from an N95, though they “look” pretty much the same. The N designation means it can be worn for a shift. 95 means only 5% of the 0.3 micron test particles get through (so it protects you from 95%) …


   N95 masks with exhalation valves were designed only to protect the wearer, and not other people. They not only release unfiltered air, they propel it, like putting your thumb over the end of a garden hose. We can fix this! But we need to do so.


   “Respirators with exhalation valves can be used in a healthcare setting when it is not important to maintain a sterile field (an example of an acceptable practice would be when taking the temperature or blood pressure of a patient). Respirators with exhalation valves should not be used in situations where a sterile field is required (e.g., during an invasive procedure in an operating or procedure room) because THE EXHALATION VALVE ALLOWS UNFILTERED EXHALED AIR TO ESCAPE into the sterile field.” [Quote from CDC, emphasis mine.]

   We’re trying to avoid infecting each other. Prior to this pandemic, it was rare for there to be concern about infecting others through the outflow valve except during surgery. We are now in a new situation in which we all need to be concerned. At the choral rehearsal in Skagit Valley, 45 of the 60 participants came down with the virus, and two died. That group was not touching, and was sitting spaced apart. Singing appears to add power and range to exhalations. And unfortunately, masks with valves appear to do the same. So, put strong tape over the valve intake, on the inside, while touching the mask as little as possible. Wash your hands first.

  Please help spread this word, because it hasn’t yet gotten out in the world.


A friend wants to make masks with her new sewing machine. She’s in the at-risk population so can’t really go out & shop for the things she needs: 100% cotton fabric & 1/4″ elastic. Does anyone have some to share? I will be glad to pick up from your porch/steps & deliver to her porch. 

Jennifer Dannenberg 510-604-5279, Lynn St

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