Robins SPARK respirator mask v2

This design has been tested and is suitable for community use, but at this time does not meet the full requirements for use in a clinical setting.

Submitted by:

Lt Col Jay Vizcarra

Sat, 2020-04-04 01:21

Vertical Tabs

General Information

Model ID

3DPX-013505

Category

Labware & Devices

Device Use

Safety and Personal Protective Equipment

Keyword(s)

PPE, mask, FFF, FDM, TPU, HEPA filter

Developed by the Robins SPARK Innovation Hub, Robins Air Force Base, in collaboration with Mercer University and the Air Force Advanced Technology and Training Center. This N-95 respirator alternative provides the capability to utilize recommended filter substitutes like 1500 rated or above HEPA (demonstrates minimum removal efficiency of 99.97% particles greater than or equal to 0.3 um in diamter). NOTE: There are different variaties of HEPA which utilize synthetic materials; Please ensure the material you choose does not contain fiberglass. Additional information on HEPA via NIOSC documentation: https://www.cdc.gov/niosh/docs/2003-136/pdfs/2003-136.pdf

The mask was printed in TPU material for mask flexibility to accommodate a better seal and with PLA for the inner filter adapter to secure filtration material. Successful qualitative fit tests were conducted at the Coliseum Medical Center, Macon.

The design includes a larger filter area to allow for easier breathing.
Silicone tubing was used around the inner edge of the mask to increase seal effectivenss (1/8" ID, 1/4" OD, 1/16" thickness).

NOTE: This 3d Printed substitute does not guarantee 100% protection against the transmission of the COVID19 and is intended to use as is. However, it will at least offer some increased protection which has been reinforced by research in materials, design, and qualitative testing.

Credit to the following:

SrA Aaron Dabney, USAF
SSgt Jason Barnhart, USAF
SSgt Imani Burnett, USAF
MSgt Benjamin Weiland, USAF
MSgt Andrea Weiland, USAF
MSgt Luis Torres-Salas, USAF
Dr. Joanna L. Thomas, Mercer University
Mr. Jacob Sokolove, Mercer University
Mr. Sagar Patel, Mercer University
Mr. Colin Petherbridge, Mercer University
Mr. Brian Weaver, AF Advanced Technology and Training Center

Please contact Robins SPARK at Robins.Spark@gmail.com for any questions.

Segmentation Software

Slic3r

3D Modeling/CAD Software

Autodesk Fusion 360

How to Make

Printer Make/Model

Lulzbot Taz Workhorse

Prusa

Makerbot Method X

Print Units

Printer-specific Build Instructions

Specific material

TPU and PLA

Number of prints per build

Build time

Pre- and Postprocessing Instructions

Manufacturer Instructions:

For print sizes: Use the following percentages for both sizes: 100% = Large, 95% = Medium, 90% = Small

Mask - Utilized TPU and printed with a 0.4 nozzle at approx 230-240C (pending on type of TPU used; see optimal temps with your TPU manufacturer) with a layer height of .2mm and 20% infil. You can also chose to configure for 4 walls and 10% infil. When printing with TPU, slow down print speed to ensure a good print especially for the first layer (20 or even 15 mm/s). No retraction was used. TPU printing may take some time. PLA can also be used in place of TPU. In this case, adjust printer to match your optimal PLA temps (per manufacturer) and use same settings of .2mm layer height with a .4mm nozzle, 20% infil or increase walls to 4 walls and 10% infil.

Mask Filter Adapter - This is the inner adapter piece that holds the filtration fabric in place. Use regular PLA filament (or harder type) to ensure filter will remain secure inside the mask to ensure a good seal. PLA insert was printed with a 0.4 nozzle at approximately 210-215C with a layer height of 0.2mm.

Filtration Fabric - EnviroCare HEPA cloth vacuum bags (synthetic / polypropylene material) 2000 series (or better can be used) were utilized which provide up to 99.97% filtration of particles up to 0.01 micron. Cut fabric to the shape of the Mask Filter Adapter with at least 15-20mm overlap to enable it to wrap inwards when securing the Mask and Filter Adapter together.

Assembly - When assembling the mask, filter adapter, and fabric, simply lay mask on flat surface with inside of mask facing up. Align filtration fabric inside the mask to match the shape of the opening (where the filter adapter will go). Finally, carefully align the filter adapter (trying to keep the overlapping fabric even) and simply push filter adapter into place to secure fabric with a tight fit.

Strap - Regular bungee-like cord was utilized however any strap can be used. Cord can be fastened with a knot like shown in the pictures.

Silicone Tube - The following silicone tube was utilized to provide additional seal reinforcement:
McMaster-Carr Product #5236K506 High-Temperature Silicone Rubber Tubing for Air&water Soft, Durometer 35A, 1/8" ID, 1/4" OD, Opaque White, 25 ft. Length

Simply cut the silicone tubing to match a length that will cover the surface area that will contact your face. Cut with a little excess to ensure a completed circle when fastened to the mask. With a small amount of superglue, fasten silicone tubing along the inside and very edge of the mask (see photos). go slowly to ensure tubing is straight and adhering to the mask with no gaps. When the silicone tube reaches end to end (completing the circle around the mask), cut the excess to complete the circle leaving a hairline or two extra to ensure the ends are snug to one another (naturally pressing into each other). A little drop of glue on the ends can also seal the deal! If there are any noticeable gaps where air seems to be escaping near the chin area, additional tubing can be cut (slit longways into a half-circle) and fastened on top of first tubing layer.

Attribution

Attribution Instructions

Pls credit Robins SPARK, Mercer University, and ATTC when applicable.

Documentation

Additional Image(s)

Reviewer Notes

Dear author,

Please add specific instructions for manufacturing and assembly and bill of materials (specifically source for HEPA filter) before further testing can be done.

Thank you.

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.