"Billings" Filter for COVID-19 MASK

thingiverse

This is an easier approach to installing filters, as demonstrated by the team at Billings Clinic in Montana. https://www.billingsclinic.com/foundation/3d-printed-surgical-mask/ I simply took their design and scaled it up to fit the COVID-19 Mask on Thingiverse. The simplicity makes it possible to use a thin filter or cloth without worrying about the front plate coming loose. The goal is to cut one surgical mask into multiple squares, allowing for more than one use, but an air filter can also be disassembled to work effectively. Consult the MERV Rating of an air filter before making your choice, as there is significant variability. MERV 13 to 16 filters are rated for particles ranging from .3 to 1.0 microns. https://www.grainger.com/know-how/equipment-information/kh-what-is-merv-rating-air-filter-rating-chart/ I can attest that a HEPA-rated air filter or a HEPA vacuum bag may be too difficult to breathe through to be effective.