This photo shows the gap between the mask and the adjuster, between the nose and the cheek-bones. Fix The Mask solves it by having "fins" or, in the open source version, by adding a ball of cloth, tissue paper, etc.Same as the photo, but as a diagram.
Surgical masks often have a simple design in which the fit is not good. To a lesser extent, this happens with a number of FFP2/N95 masks which have a poor fit. On twitter, user "fitmyworld" seems to have knowledge & experience.
The lack of fit allows aerosols to leak in and out, which reduces their effectiveness. In addition, moisture fogs glasses.
Therefore, the initiative Fix The Mask designed an add-on to improve the fit. On that website there is an opensource design (link).
In this case, the ear saver concept, invented and popularized by the maker movement during the first waves of Covid, is also used, generally using 3D printing.
Bring text and photos. Elements to make a homemade mask adjuster. Photograph by Esther Cuadrado for LibresDeCovid and Aireamos.
Elements needed: 3 rings of elastic, and an ear saver. The ear saver could be made from recycled bottle plastic.
Homemade mask adjuster in place. Photograph by Esther Cuadrado for LibresDeCovid and Aireamos. Adjuster in place: it is placed on the outside of the mask, surrounding the mouth and nose, and then tightening towards the ear flap, with sufficient tension until leakage is reduced.
Difficulties:
Not useful if you need to put it on & take it off frequently.
"3 shaped" curve between cheekbones and nose still leave leakaging. See below.
Ideas for improvement:
To make it easier to put on and off the frame could be more rigid. See the other designs below.
The "3 shaped" gap mentioned above is avoided by fixthemask using extra ridges, on left and right, that fill up that gap. How could we make something personal for each face, yet simple to do at home?
First, get the shape of the gap using a "contour gauge". The simplest version is with cooking sticks (1-2 mm diameter) run through a the holes of a strip of cardboard. Done between the cheekbones, this would give us the "3 shape" for that particular person.
Now we'd need to create the filler and make sure it stays without being displaced towards the eyes which would make it both useless & uncomfortable. Testing & iterative redesign needed.
