It’s March 2020. The COVID-19 pandemic hits US shores and we are woefully under-prepared–my wife is a nurse in NYC and informs me they do not have enough of the correct face mask to prevent transmission of the virus to doctors, nurses, and clinical staff.
Supplies are low, and replacements are unavailable or delayed.
Not only this–alternatives of the same or similar level of filtration are unavailable as well, due to the medical shortage.
Let’s get to work.
These 3D-printed parts can make an old, inadequate respirator safe for use in a high-contact, high-exposure setting using a commonly available item as filtration media.
Exploded view of the mounting adapter and filtration cartridge:
Alternatively, should a limited supply of n95 masks be available, this system could stretch the supply substantially. By cutting up the donor mask, theoretically, the material from one mask could be used to protect as many as eight people.
Files have been updated; now these cartridges are compatible with disposable 3M respirators, standard 3M respirators AND standard MSA respirators.
ASA (Polylite) Selected for main cartridges for its resistance to exposure to environmentals including heat, humidity, and UV radiation (these can be sterilized and reused indefinitely)
TPU (ninjaflex)Selected for custom-fit, airtight gaskets
Donor mask used:3M 5201 Disposable Half Face Respirator
Filtration medium used:Cotton Rounds
I have made these parts open source and they are available for free download at grabcad.com and thingiverseright now. At last count, these files have been downloaded over 525 times by users in more than 14 countries.