S.A.F.E.
Cartridge System

The Self-Assembly Filter for Emergencies (S.A.F.E.) Cartridge System is a DIY mask system built using common supplies to leverage the benefits of HEPA filtration. In the face of a global COVID-19 pandemic, I lead a team of physicians and engineers at the Medical University of South Carolina in the development of an easy-to-make mask system for medical workers.

This mask project not only engaged multiple universities and organizations in South Carolina and across the United States, but garnered attention for its potential for use in multiple countries around the world.

This was released as an open-source project, available for anyone to create and use. Files for this project can be found at https://bit.ly/3CLm0pQ.

How can you make an impact while quarantined?

A national shortage of PPE for healthcare workers at the start of the COVID-19 pandemic created a dire and urgent need for new solutions to be put into place. Sitting at my desk in my apartment, I began to brainstorm and research what made N95 masks unique. Looking into different filtration mechanisms, I drew upon my experience and research on air filtrations from a previous project to arrive at a substitute for N95 mask material: HEPA air conditioning filters.

Air conditioning meets the human respiratory system

HEPA filters are commonly used in air conditioning units, and come in a wide variety of sizes and cartridge arrangements. These types of filters are also used in environments such as in operation rooms as a way to maintain clean airflow. Some of these HEPA filters can filter particles at 0.3microns at a staggering 99% efficiency, out performing N95 masks which filter same-sized particles at only 95% efficiency. Identifying HEPA filters as my filtration material, I knew I was onto something and began to prototype.

Concept to Functional Prototype in 15 Hours

Using materials commonly found at hardware stores, I began to prototype the S.A.F.E. Cartridge System at home. The first prototype was a simple box with a HEPA filter glued into it. That prototype quickly evolved into a 3D-printed model that can be easily assembled. Upon testing, I found that the pressure to breathe through the mask can cause it to lift from the face, so I added a one-way valve made from the rubber of a kitchen glove to the mask. The quick, iterative prototyping process allowed for rapid development of the mask system.

Approval for Use

With the assistance of MUSC administration, the S.A.F.E. Cartridge System was given a fast-track towards emergency approval for use. Days after finalizing our mask prototype and developing a custom 3D-printed mask with a window-sealing foam gasket, we passed an emergency PPE safety control. This proved to us that the mask can not only adequately filter air, but also that there are no areas of leakage in the mask’s seal against the user’s face. With this approval, the mask moved onto distribution.

Project Guides and Outreach

The final S.A.F.E. Cartridge System was documented in a project guide that informs users how to create a mask of their own at home. The project was posted as an open-source package so that people around the world could print and use our masks to support their local healthcare workers. The support was staggering, with thousands of masks being printed locally in South Carolina, across the U.S., and globally in 4 different countries.

Innovation Has a Place in Healthcare

The S.A.F.E. Cartridge System was a device with a widespread impact. Empowering schools, libraries, and hobbyists, the mask gave people at home an opportunity to support their healthcare workers in a tangible way. Since this project, two provisional patents have been filed and the S.A.F.E. Cartridge system was put on display at the South Carolina State Museum in Columbia, SC to show how innovation played a role to combat the COVID-19 Pandemic. The mask has also given our team the “I am an MUSC Innovator” Award in 2020.

More information about Jetter can be found at https://bit.ly/3CLm0pQ.