Filters and filter pockets
Some reusable face masks include a pocket where you can slip in a disposable filter as an extra layer.
Commercially-made face masks may come with a more high-tech filter provided, but you can also use tissue paper or the coffee filter in a tweak. Filters manufactured definitely for face masks are usually traded separately and often ready from melt-blown nanofibers. They can filter microscopic particles similar to face masks used in industrial and medical-grade covers. In our tests, an Earloop face mask with a disposable filter did well at blocking bacterial particles. Still, it was a bit harder to breathe through, and it is also not wholly sustainable as you have to dispose of the filters regularly, in a few cases after each use.
Opt for multiple layers – many tests showed a clear difference between single-layer face coverings and faced masks with a double or triple layer. It is better if your multiple layers are ready from different fabrics. Single-layer face wrappers were better than nothing at all, but in some circumstances, only marginally. The WHO advises the ideal combination of material for non-medical face masks is three layers consisting of:
- An innermost layer of a hydrophilic material
- A middle hydrophobic layer of synthetic non-woven material like polypropylene or a cotton layer
- An outermost layer is prepared of hydrophobic material (like polypropylene, polyester, or their blends)
Some face masks have a built-in metal wire, or a foam nose seal, diagonally the bridge of your nose to help mold the face mask close to your face to avoid gaps where air can leak out and to have it in place. It is helpful if you wear glasses to help stop them from steaming up.
Different face masks have different ways of fastening to the face: elastic straps or fabric ties are standard. To reduce the risk of infection, you can remove the face mask by using its straps and not touching your face or the face mask. It is worth checking these have sufficient give, so they are not uncomfortable to wear but help Earloop face mask fit closely to your face. Some handmade face masks may use ribbons or fabric ties, and some that go around your head instead of sitting behind your ears.