Meet the UW engineers who are changing the facemask game

Pivoting for new problems: Engine researchers drive mask insights

UW College of Engineering

When the COVID-19 pandemic hit the United States in spring 2020, Mechanical Engineering Professors Scott Sanders and David Rothamer were among the UW-Madison faculty, staff and students who stepped up and devoted their expertise and ingenuity to help in the fight against the novel coronavirus.

Sanders and Rothamer, who are experts in measuring gases and particles in internal combustion engine processes, pivoted to study mask materials, construction, fit and filtration. And they were well positioned to help, since the tools they already use in their combustion systems research can measure particles in the same size ranges as those expelled by breathing and talking as well as coughing and sneezing.

They conducted extensive testing to measure the effectiveness of different types of face masks at filtering aerosol particles.

In those tests, they used a mannequin wearing masks of varying styles and materials to demonstrate how tiny particles from a human breath and larger droplets from a cough escape from, or remain inside, each mask. They outlined the results in a video showing each mask’s effectiveness at containing both.

A key finding of their research is that the effective filtering efficiency increases if there are no gaps at the top, sides and bottom of the mask that could allow virus particles to escape. That prompted them to work with Lennon Rodgers, who specializes in engineering design and directs the Grainger Engineering Design Innovation Laboratory, the engineering makerspace at UW-Madison, to develop a simple and inexpensive fitter that ensures a tighter mask seal around the wearer’s nose, mouth and face.

Known as the Badger Seal, the mask fitter is a soft, adjustable “frame” with elastic worn either as ear loops or behind the head. With readily available materials, such as elastic cord and foam-covered wire or pipe cleaners, the fitter is easy to make at home in minutes. Production facilities beyond the UW makerspace are also beginning to make the Badger Seal. Read more …