Customizing masks to fight the spread of COVID

University of Waterloo researchers are developing personalized 3D-printed mask components for front line health-care providers as well as patients who regularly visit medical facilities for treatments such as dialysis and chemotherapy.

Members of the  Multi-Scale Additive Manufacturing (MSAM) Laboratory have produced a number of prototypes based on approved design guidelines from Health Canada and the National Institutes for Health.

Lab members explored the idea of using reusable 3D-produced materials for the mask frame that holds a disposable filter sheet inside of it.

“We are using our specialized technology here on campus that can print multiple materials – both hard  for the mask frame and flexible for the seal –  at the same time,” says Ehsan Toyserkani, a mechanical and mechatronics engineering professor and research director of MSAM. “It requires a very sophisticated 3D-printing technology that is not available at many universities.”      

Unlike most one-size-fits-all masks currently available, MSAM lab researchers are customizing masks by adjusting shapes and sizes for children and adults of all ages, including seniors, whose facial tissue and structure greatly vary. Different ethnicities with unique bone structures are also being taken into consideration.

Mihaela Vlasea, a mechanical and mechatronics engineering professor and the associate director of MSAM, said the benefits of digital manufacturing are that changes can be made to the design for both fit and comfort more easily than with conventional production during which it’s more difficult to  make micro tweaks once the mold has been completed.

“That’s where we think we can actually pivot,” she says. “For instance, once we have a prototype in use someone can give us a call and say ‘I think you need an extra millimetre here or there’ and that’s the type of change that isn’t costly or time-consuming to make.”

The biggest challenge the lab currently has is finding the best disposable filter sheet for the mask. Members are looking for one that will effectively protect against the spread of COVID-19. In addition, materials for the mask frame that are acceptable for skin contact and can withstand sanitation are also being investigated.

Co-op student contributes to research

Cecilia Cancellara, a second-year nanotechnology engineering student, spent this year’s winter co-op term working in the MSAM lab.  She started out in January examining the characterization of metal powders but quickly redirected her research to sourcing materials for personal protective equipment in mid-March after the coronavirus outbreak was declared a pandemic.

“It was a pretty smooth transition,” she says.  “I had a previous co-op position with Waterloo’s mechanical and mechatronics engineering department that involved juggling different projects, many of which I hadn’t had prior experience. I think that prepared me very well for learning on the fly and adapting to new challenges to get done what needs to be done.” 

Cancellara credits the support received from all MSAM lab researchers for being able to successfully work remotely on her research and findings that she continues to document her findings in her co-op report.

Looking for testing partners

While the lab has been relying on financial support from the Advanced Manufacturers Consortium for its work, it has applied for a government grant to support hospitals directly with research and development.

Vlasea said that hospital representatives are working with her team are continuously looking for partners to help with the testing of prototype masks. The list included University colleagues Bill Anderson, a chemical engineering professor who has conducted extensive research on the disinfection of surfaces using ultraviolet (UV) light, and Zhongchao Tan, a mechanical and mechatronics engineering professor who specializes in pollutant and  particulates testing.

Lab employees are planning to work with Anderson, Tan and other researchers on campus to test how well the 3D-printed materials stand up to sterilization using various solutions.

Vlasea said the lab’s ultimate goal is to get the right product with the right fit into the hands of doctors and patients, specifically for long-term use.

“It may not have been the case before the pandemic where doctors would have to wear a mask 24 hours or however long their shift is, but now we know that is the standard norm,” she says.

In late March, the MSAM lab shifted its production focus to 3D-printed materials for face shields used by health-care workers battling against COVID-19.

With the help of dedicated technical staff and co-op students’ remote support, MSAM is currently producing more than 100 engineered polymeric headbands and bottom reinforcements each week for distribution in Ontario. The lab is looking into sending the parts to Quebec and other regions where there may be a storage of face shields.