The three types of mask vary only in ties and size.

JUMP TO:
Mask type 1 (long ties, latex-free)
Mask type 2 (elastic ear loops)
Mask type 3 (long ties, latex-free, for children)

We have selected the style of mask for this site based on available research, input from healthcare workers, and plenty of fit-testing! It is similar to a mask style often called the "Olson" mask (or a few other names), though it has been improved:
(1) it includes a dart for a snug fit under the chin (loose/floppy fabric in area was major flaw)(2) it has been simplified to make it both faster/easier to sew and lighter to ship.

This mask allows a disposable surgical mask to be inserted into the mask as a filter (just cut off the elastic loops), and the research indicates this is the best option for filtration material in terms of a balance between breathability and filtration efficacy. There are materials with better filtration, but most are harder to breathe through, making the mask unsuitable for long-term wear. You can also insert a PM 2.5 filter if you have one, though the ones on the market now are fairly small, so it seems likely you will just draw air around the sides of the filter, rather than through the filter. In a pinch, people are using cut-up HEPA filters (such as from vacuum bags, air conditioning filter, etc). You can even using paper towels or facial tissue if it is all you have access to—not ideal, but still better than nothing. And there is some evidence that a layer of canvas/denim is a good choice (in the absence of lighter-weight filter availability). The fabric of the mask itself is too porous to effectively filter out aerosolized virus, so these are intended to be used over a mask or with an inserted filtration layer.

An important note: without a tightly-fitting mask/respirator that forms a seal at all edges, any masks such as a typical surgical mask, with gaps around the sides, do have the problem of some air leakage around the sides. Unless you're wearing your fabric mask over a properly-fitted N95 mask, it does not provide complete protection. Don't assume that because you're wearing a mask, you are entirely safe. It is important that when you first don the mask, you ensure the best/most comfortable fit, since you need to avoid touching your face once out and about. Ideally, look in the mirror as you adjust the wire around your nose. The goal is to reduce air gaps around the edges as much as possible. But remember that no mask is perfect, and a mask you wear is better than one you keep in your pocket because it is too uncomfortable.

This mask's fit makes it appropriate for wearing over an N95 (disposable) mask to prolong its life. Once soiled, an N95 mask is no longer effective and must be discarded. Wearing a fabric mask over the N95 significantly prolongs its life by preventing soiling. This is obviously more applicable in certain environments.

This version has long ties that can be tied behind the head. It has no elastic and is latex-free. The upper tie is secured at the back of the head, and the lower tie is secured at the back of the neck. Individuals with longer hair will want to experiment with tying up hair at different heights at the back of the head to see what works best to keep the upper tie securely in place (and not prone to slippage). It is recommended to tie up your hair before donning the mask to better avoid touching your face/hair while wearing the mask. It is also possible to make the ties into loops that go behind the ears, but this creates bulky loops that may not be comfortable for long periods.

This version is almost identical to mask type 1 above, but it has thin elastic loops which go behind the ears. You will knot the elastic into loops at your preferred length, trim the excess, then rotate the loop until the knot is hidden inside the fabric. You want a snug fit so the mask forms a nice seal around your face, but not so snug that it pulls your ears forward (it may seem fine at first, but it begins to hurt before long). The elastic may contain latex, so it is not suitable for those with latex allergies. The elasticity of the loops will start to fail with time, especially when washed in hot water (recommended), so this mask will not last as long as one with ties.

This mask is the same as mask type 1, but sized for a child's face. It has long ties that can be tied at any length behind the head and is latex-free.