Cloth mask tested by WSU nursing faculty could offer more protection

portrait of a woman wearing a mask
Shawn Brow, a nurse anesthetist in Spokane, is working with College of Nursing faculty to test a prototype mask design that offers more protection than a disposable or plain cloth mask. 

Two faculty members at the Washington State University College of Nursing are testing a fabric mask made with a filter available at big-box stores as an alternative to sometimes-scarce N95 masks.

Marian Wilson, assistant professor at the College of Nursing in Spokane, and Roschelle Fritz, assistant  professor at the College of Nursing in Vancouver, began collaborating this spring when the devastating effects of the COVID-19 pandemic were coming into focus.

“It was clear PPE (personal protective equipment) was going to be an issue and nurses on the front lines were being asked to wear their N95 masks for an indefinite period of time,” Fritz said, referring to respirators that filter out 95% of particles in the air. “Marian and I just delved into the literature, trying to see if there was anything out there that could protect people.”

Wilson’s colleague and co-investigator Shawn Brow, a nurse anesthetist in Spokane, knew a local seamstress interested in sewing masks for health care workers. They began to explore designs and ideas to create a homemade mask.

Using research funding from WSU Vancouver, Wilson and Fritz worked with Brow to acquire and “fit test” the masks at Arbor Health Morton Hospital in Morton, Washington.

Fit testing is required by the Occupational Safety & Health Administration for people who use N95 respirators to ensure a tight seal between the mask and a person’s face. It involves donning a mask, then testing whether the wearer can smell or taste specific things, like sweet or bitter scents. If the mask fits right the wearer shouldn’t be able to smell or taste anything. Masks are also sometimes taped to the face to enhance the fit.

“We wanted participants to simulate the tightness of the feel they would get with an N95 mask using just tape and a homemade mask,” said Wilson.

Two nurse-engineered prototypes were tested; the second model failed all fit tests. But the first model, which uses a filter, passed fit testing for 12 of the 28 participants. Any hospital personnel who might be asked to enter an airborne isolation room were eligible to take part in the study, which included nurses, physicians and housekeeping staff.

cloth masks
The prototype mask design includes a pocket for a piece of a household air filter that’s readily available at big-box stores.

Fritz said the pass rate would likely have been higher if taping had been done consistently.

The mask is made using cotton fabric, a long cord – which could be a shoestring – and a piece of a 3M Filtrete 1500 household air filter, which is inserted into a pocket inside the mask. Fritz estimated the cost of materials at about $10 per mask.

Wilson and Fritz would like to continue refining the cloth mask design and evaluating its effectiveness, but for now their goal is to let people know there is a better-quality alternative to disposable masks or plain cloth masks. The pattern is available from Georgette Thornton, a local leader with the nonprofit Days for Girls International.

The masks could be useful for people trying to protect themselves or their family members, or for healthcare workers who encounter a shortage of N95 masks.

“The other aspect to this is waste,” Wilson said. “We want to support high-quality reusable products that work for the average person in the community.”

Said Fritz, “This is by nurses, for nurses and anyone else who needs it. Nurses have the heart of the population in mind.”

–Story by Addy Hatch

Categories: General