THIS MASK WAS CREATED USING:
1. Polylactic acid (PLA) (3D printer filament)
2. West System Marine Epoxy (as an external coating)
3. Smooth-On Dragon Skin Silicone - tested skin safe, used primarily in special FX prosthetics
4. Dentec NIOSH R95 / N95 Filter Pad
5. 1/2 inch elastic band
6. Marine vinyl head strap (in some cases)
In response to the PPE shortage brought on by the COVID-19 pandemic, makers around the globe worked to design and fabricate DIY PPE using 3D printing technology. After reviewing several designs for last-resort, replacement respirators and masks, I generated the design shown here.
These masks have been built to accommodate Dentec NIOSH rated R-95 and N-95 filter pads which were in relatively large supply compared to 3M and Honeywell filters and cartridges. I’ve worked to assure the masks form an airtight seal around the user’s face while still maintaining comfort and the ability to be disinfected. A lip has been built out from the edge of the mask, allowing enough surface area to attach a foam seal. The foam has been sealed using multiple layers of skin-safe silicone to fill in the foam’s porosity while still allowing for flexibility and comfort.
The exterior of each mask has been sealed using West System epoxy resin, which expels very low VOC and out gasses fast. Additionally, the interior of the masks have been sealed with silicone as well. These two layers of additional sealant, both interior and exterior, fill any tiny voids that may exist within the layer lines of the 3D print. In addition to the mask bodies, caps, gaskets, head straps, and elastic sliders have also been fabricated by way of 3D printing.
To date, nearly 50 masks, along with a week's worth of replacement filter pads, have been donated to both healthcare workers and nursing students in the Norfolk, Virginia area.
Please click here to download all STL files for this project. The download includes mask body files of two sizes: small & large. All accessory files (cap, gasket, head strap, sliders) fit both the small and large mask bodies.
FILTER PAD REPLACEMENT:
The cap attaches to the body of the mask using a bayonet attachment. To replace the filter pad, turn the mask cap counter clockwise until it releases from the body of the mask. Pull on the gasket to remove it from atop the filter. You may alternatively push on the gasket from the interior of the mask to remove it.
Given the current shortage of PPE, alternate materials are currently being used in place of NIOSH rated filters. Such materials include the fabric found inside non-fiberglass HEPA filters, Halyard 600, blue shop towels, and even small portions of N95 masks. To use any of these alternate materials, use the pink gasket inside the mask as a template to trace a circle onto your chosen filter material. Doing so will provide you a patch of material that will fit perfectly inside your mask. Though, when cutting your material using your traced gasket, you may want to cut a bit beyond your drawn line to assure that there will be no air gaps inside the mask once the material and gasket are inserted.
The more materials you layer, the more protected you will be. But remember to allow enough airflow to breathe comfortably!
TO CLEAN THIS MASK, YOU MAY:
1 . Wash it with soap and water
2. Wipe it with alcohol
* Other methods of disinfecting have not been tested.
* Do not submerge in water.
* Do not expose to high heat as a method of disinfecting.
Marine vinyl as an alternate to the 3D printed head strap.
Pretty pink, baby blue.
ALTHOUGH EVERY ATTEMPT HAS BEEN MADE TO ASSURE THE EFFICACY OF THIS DESIGN, THE MASK HAS NOT BEEN FIT TESTED.
USE ONLY AS A LAST RESORT TO PROPERLY CERTIFIED PPE.