This device is a general purpose face mask intended for use in the community and is not suitable for use by a healthcare professional or in a healthcare facility or environment, as described in FDA Guidance Enforcement Policy for Face Masks and Respirators During the Coronavirus Disease (COVID-19) Public Health Emergency, Section V B. This device has not been tested to assess the out-gassing limits of the material or their corresponding health effects.

This respirator facemask can be built of common materials plus small, easy-to-print 3D printed parts, and a small (55mm) disk of filter material. The mask conforms to the face, with the Tyvek forming an impermeable membrane, concentrating the breathing airflow through the filter housing. The filter housing is made of 2 identical 3D-printed parts that snap together over the filter and around the edge of a circular hole in the Tyvek. The filter material is a 55mm diameter disk of material (hopefully HEPA-certified) that permits sufficient airflow.

The 3D-printed parts are a quick print, using modest amounts of filament. The idea is to make lots of these parts quickly, since 3D printers are the limiting resource.

This mask is intended for emergency use during this pandemic when manufactured products are unavailable.

The following files are supplied:

maskresp40.stl --3D-print Filter Housing half, 2 of these snap together.

maskresp40loose.stl --Variant of maskresp40.stl with looser tolerances

MaskPatterns.PDF --Terse instruction sheet and 4 different-sized mask patterns

MaskInstructions??.PDF --Extensive illustrated instructions and discussion. This file is versioned.

NoseThingy2.stl --3D-print nose-shaper part, holds wire

NoseThingy.stl --Older, shorter version of NoseThingy2.stl

Disk_stencil.stl --3D-print stencil for cutting filter disks (optional)

Plain paper can be substituted for Tyvek, but it is not as durable. Tyvek is available as office supplies, construction material, and protective clothing. Do not print Tyvek with a laser printer. Tyvek is a trademark of DuPont.

I am really interested in real-world feedback on the use of these masks, especially by clinicians, so please comment.

Note that this design is also available at: https://www.thingiverse.com/thing:4257706/

The accompanying documents (look under "Extras" tab) show how to make a face mask using 2 of these parts... MaskPatterns.PDF has four 2d printable patterns for paper-like materials, regular and large size, regular and longer length, MaskInstructions06,PDF has illustrated instructions. Note that DiskStencil.stl is just a round stencil for cutting out filter material to dimension. Note that NoseThingy,stl and NoseThingy2.stl are for making something to mold the mask to the nose bridge (use TPU --needs to be flexible), Then insert wires. [more detail in instrructions]

17 April 2020 Update, files and documents all in place.

18 April 2020 Update to .PDF files, minor.

27 April 2020 Title, keywords, and descriptive summary changed.