U of M designers build prototypes to fill the urgent need for masks, ventilators

A mannequin wearing a surgical mask sits next to a machine.
The University of Minnesota is trying to fill some of the urgent need for masks and ventilators with handmade solutions. The College of Science and Engineering and the Department of Design, Housing and Apparel teamed up to create masks that health care workers can use in a pinch.
Courtesy of the University of Minnesota

Few supplies are going to be as important as the protective masks that can prevent the coronavirus from spreading to the doctors and nurses treating the sick.

But with shortages of masks widespread, researchers and designers at the University of Minnesota are turning to the art of origami — kind of.

“Using what is basically the equivalent of N95 filtration material, folding it into a mask that is form-fitting,”said Tim Schacker, vice dean for research at the U of M’s medical school, and also an infectious disease doctor.

Medical school researchers, staff from the College of Science and Engineering and the Department of Design, Housing and Apparel recently teamed up to create masks that health care workers can use in a pinch. Scientists from 3M, which makes N95 respirator masks, advised the team and Schacker said the U is now testing its prototype masks.

“They built multiple prototypes, they looked at multiple alternatives, and they finally came up with a solution,” he said.

It’s not as simple as it sounds.

Federal regulators have determined there are five different versions of human faces to fit. U of M researchers have been trying to accommodate these variations. To make sure the folded masks seal tight to the face, the team tests them with bitter aerosols. If the mask wearers can taste the bitter flavor, that’s a sign that the mask leaks.

“We think we’re close [to achieving a proper seal],” said John Bischof, director for the Institute for Engineering in Medicine. He said the team also thinks they can make the masks by the thousands — or as fast as people can fold and tape them together.

A woman wearing a surgical mask.
U of M researchers and designers are testing this prototype mask to see if it can be used as a safe alternative to scarce N95 respirators.
Courtesy of the University of Minnesota

Components for the masks have to be cheap and readily available.

The prototypes use bulk filtration material, as well as nose pieces from Bedford Industries, a twist tie manufacturer in Worthington, Minn.

The result isn’t pretty. The masks look like a paper hat tied to someone’s face.

And they are not an equivalent replacement for N95 respirators and the rigorous testing those masks received. But researchers think their version of the masks could be an acceptable, safe alternative.

“This is in the dire case that we have no more N95s,” said Bischof.

Linsey Griffin, co-director of the university’s Human Dimensioning Laboratory, came up with the initial mask design. She said the U team has made remarkable progress toward its goal of producing a mask that fits properly and can be mass-produced cheaply.

”I mean we’re talking about two weeks that we have gone from zero to something that is close to viable, close to meeting the N95 standards,” said Griffin.

A surgical mask.
A prototype mask developed by U of M researchers and designers.
Courtesy of the University of Minnesota

Ventilators are another lifesaving item that’s in short supply.

A different team of U of M researchers has developed a simplified ventilator that they hope can be used, if hospitals run out of high-tech breathing devices.

They submitted the design recently to the Food and Drug Administration.

The inspiration came from vintage breathing machines, said Steve Richardson, a cardiac anesthesia fellow at the U. He said he was talking with a colleague about the ventilator shortage and they found a book with some simple ideas.

“I think it was published in 1972 and it had all these old ventilators in it,” he said, “and we were looking at it, [and thinking,] ‘OK, what could we make?’”

Their prototype uses an electric motor supplied by Thief River Falls, Minn.,-based Digi-Key, a major electronics parts supplier. Richardson said the motor forces squeezes a large plastic bulb to force air into a patient’s lungs.

“The device that we ended up with is you know, 1950s style of ventilation,” said Richardson. “It’s an extremely simple machine. It’s basically a one-armed robot.”

He said the FDA has some provisions for emergency circumstances that will allow improvised devices — though it’s not clear if the U’s device will be approved. Richardson and his colleagues have made their plans available freely online, so others can experiment with the design.

University researchers say, ideally, health care workers wouldn’t need to rely on either substitute masks or ventilators. But if the pandemic overwhelms Minnesota’s health care system as it has in other places, they want to give health workers and patients some alternatives that have at least some science behind them.

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