Designed to utilize available non-medical filter material to make an easy to assembly and sanitize mask. The mask can be custom heat formed using hot water. Requires half inch elastic for bands. I am currently using a combination of a MERV 12 AC furnace filter and a HEPA filter cut to 3.25" squares to make masks for my family. This appears to be the best materials I can source locally to make something with (hopefully) higher protection than a cloth mask. I decided to use both because the cost of the HEPA filter is high and in high demand. The MERV 12 material is used as a pre-filter for the HEPA filter hopefully increasing the effectiveness and life of the filter.

I have made my best effort to provide and design a high quality mask that utilizes common filter material due to the shortage of medical grade PPE. My hope is this will alleviate some of the supply chain strain on our health care system by allowing citizens to make their own PPE that they feel comfortable wearing in public. Here are some of the resources I have turned to when researching 3D printed PPE.

Paper describing the effectiveness of various grades of AC filter and HEPA filter

• http://3jboicbe6zk2otw9dphoerro-wpengine.netdna-ssl.com/wp-content/uploads/2020/04/N95-Alternative-Mask-rev04.pdf
• Please see this website for the source of the paper and more information https://enmed.tamu.edu/diymasks/

FAQs on 3D Printing of Medical Devices, Accessories, Components, and Parts During the COVID-19 Pandemic

• https://www.fda.gov/medical-devices/3d-printing-medical-devices/faqs-3d-printing-medical-devices-accessories-components-and-parts-during-covid-19-pandemic

FDA Approves First 3D-Printed Mask for COVID-19 Support

• https://governmentciomedia.com/fda-approves-first-3d-printed-mask-covid-19-support

NIH 3D Print Exchange: Lots of approved or pending approval models available

• https://3dprint.nih.gov/

Two excellent and well documented mask designs:

• The Make The Masks design is designed to use a N95 surgical mask cut into 8 squares to make each mask go longer for each medical personnel. This design is in use in Hawaii hospitals and has passed local fitment/seal testing. Make the Masks provides fitment data on their website as well https://www.makethemasks.com/
• This is a complex modular 3D printed design. It utilizes HEPA filters and has received NIH approval. Before utilizing my mask or any non-FDA or non-NIOSH mask please review the guidelines provided https://www.makermask.com/use-guidelines.html

I am using MERV 12 AC furnace filter as a pre-filter to trap dust and extend life of the HEPA filter. From the Texas A&M paper posted above MERV 16 or HEPA should have protection near to n95. Please note disassembling the filters could compromise the filter media and reduce filtration ability. The design prints without supports and one mask can be printed in 2 hours. I used an infill setting of 15% and 2 walls thick. The filters are cut to a minimum size of 3 inches square. Two 18 inch lengths of 1/2" inch elastic is used for the straps. The straps are adjustable. I currently have only one size available and am working on a larger and smaller size.

Disclaimer Statement: The mask could be considered for possible use in certain activities while N95 masks are unavailable. If approved N95 masks are available, use those approved N95 masks first. While these masks may provide some level of particulate matter filtration that offers some measure of protection, but no guarantee, representation, or warranty is made relating to meeting or exceeding the performance standards of an N95 PPE mask certified by the National Institute for Occupational Safety and Health (“NIOSH”) or approved by the Federal Drug Administration. Any use of this type of mask is at the user’s own risk. This statement was taken from the Texas A&M paper and will be removed upon request.