Sunnybrook developing N95 mask alternative using full-face snorkel mask

April 30, 2020

Dr. Brian Li wears a full-faced snorkel mask being designed as a N95 alternativeSnorkel masksMask partsDr. Brian Li with full-faced snorkel mask

With N95 masks in limited supply worldwide, innovators at Sunnybrook Health Sciences Centre are developing an alternative form of the personal protective equipment using a modified full-face snorkel mask, should the need arise.

“This is an unprecedented time that is highlighting the need for innovative solutions to the challenges health-care workers are facing during the COVID-19 pandemic,” says Dr. Brian Courtney, a cardiologist, engineer and scientist at Sunnybrook.

Dr. Courtney is working with engineer and interventional cardiologist fellow at Sunnybrook, Dr. Brian Li. Both are leading teams of engineers, entrepreneurs and physicians in developing and testing the N95 alternative, as well as tie-back surgical masks that can be made in-house.

“In an ideal scenario, we wouldn’t need to use either of these masks, but in case we run out, we are developing alternatives that would allow us to keep doing procedures, look after our patients, and keep our health-care workers safe,” says Dr. Courtney.

Sunnybrook has long been at the forefront of medical innovation, from developing substances that soften plaque build-up in arteries to a world-first helmet-like device that uses focused ultrasound to non-invasively treat areas of the brain that were previously unreachable. These and other technologies have been developed in-house, and based on the needs of patients and Canada’s health-care system.

Personal protective equipment (PPE) — including gloves, gowns, face shields and masks — are considered essential tools for guarding health-care workers from being infected as they look after sick patients.

“In the context of the crisis, we are exploring all options,” says Dr. Jerome Leis, medical director of infection prevention and control at Sunnybrook. These options also include sterilizing and reusing N95 masks.

How it works

Drs. Courtney and Li, along with their teams, are currently testing their designs using the same testing requirements for existing N95 and surgical masks.

As an N95 alternative, a full-face snorkel mask provides shielded protection of the eyes, nose and mouth from the surrounding environment.

Using 3D printing techniques, the stem snorkel at the top of the mask is replaced by an adapter that fits widely available ventilator cartridges to filter particles in the same manner as N95 masks.

The masks and adapter would be sterilized and reused, and the cartridges would be thrown out after each use.

“We have been aggressively testing filtration efficiency, fog resistance, comfort, ventilation, re-sterilization and the risks of inadvertent contamination when putting on and taking off these masks,” says Dr. Li.

“The masks will not be used until their safety and effectiveness can be ensured,” adds Dr. Courtney. “So far, results are promising.”

Once testing is complete, Sunnybrook will be able to produce both the N95-alternative and surgical masks in-house immediately, should the need arise.

“This has very much been a collaborative effort,” says Dr. Li in reference to the group of colleagues who have volunteered their time and expertise to these projects. “Our teams are working tirelessly to make these masks a reality, knowing the urgency of the situation and the potential impact that it might make.”

These projects were also made possible thanks to a community of donors, including Canadian Tire Corporation and its Product Development Team for their support and gift of 1,100 full-face snorkel masks. Sunnybrook would also like to thank the Azrieli Foundation and Murphy Family Foundation for their generous support.


Sunnybrook continues to graciously accept donations of personal protective equipment that is vital in keeping our health-care workers and patients safe.


Media contact

Katherine Nazimek, Communications Advisor
Sunnybrook Health Sciences Centre
416-480-4040
katherine.nazimek@sunnybrook.ca