Comfortable Covid Mask

thingiverse

I used the blender add-on called FaceBuilder to create a custom mask that fits my face perfectly, but you can easily customize it to fit yours by submerging it in hot water and shaping it to your features. As of July 22, 2020, I've added files and instructions for scaling the print to match your facial contours. I designed the straps to use thin elastic, which is what I had on hand, but you can use whatever material works best for you - elastic shoelaces make excellent straps. I recommend printing it with a layer height of 100-150 microns to achieve a better seal. Alternatively, you can use food-safe epoxy to seal the holes in lower-quality prints. Some people think that because the virus is smaller than 0.3 microns, they're "trying to stop grains of sand with a chain-link fence," but the physics of filtration isn't that simple. According to this paper on HEPA filters, particles larger and even smaller than 0.3 microns are filtered out. In fact, the 0.3-micron specification is chosen because it's the particle size most likely to pass through. The smaller particles are caught due to Van der Waals forces. The experimental results show that filters are worse at filtering air with faster velocities (makes sense). So, my idea was two-fold: make breathing easier and slow down the airflow through the filters using Bernoulli's principle by increasing the inlet area. Using HEPA filters may not be a good option due to the high differential pressure required for breathing. The good news is that filtration physics remains the same for other filter media. To explore alternative options, visit this website, which uses NIOSH-approved equipment and shows promising results for commonly available materials: https://www.maskfaq.com/test-results. As of July 23, 2020, the best option they've found is Filti brand filter material (https://filti.com/product/filti-face-mask-material/). The 21-square-foot option costs $30 and should last a while. When using two layers stacked, it passes the N95 NIOSH standard, but be aware that washing the filters causes their efficiency to drop from 97% to 45%! So, don't wash your filters; just replace them. Take all this with a grain of salt - I have no way to quantify the mask's protection ability. It depends on the filter you use, how well you achieve a hermetic seal (test it by holding the mask on your face and plugging the holes with your hands), and your mask-wearing etiquette. However, recent studies show that even a rudimentary mask can protect both yourself and others. This design also accommodates glasses without fogging. I've removed the slits in the filter caps to make them more durable (UPDATE 6/24/2020). Watch for updated filter caps with a supportive grid - it's coming soon! I've added a supportive grid for the filter media (UPDATE 6/25/2020) and left the legacy version intact. Enjoy! I also added files and instructions for scaling the latest version to fit your face better (UPDATE 7/22/2020).