In the early days of the pandemic, amidst all the uncertainty, one thing was for sure: N95 masks – the personal protective respiratory devices that filter out viruses, bacteria, and wildfire smoke – were in short supply. So when materials scientists Jeff Urban and Peter Hosemann heard that a local HMO needed advice on N95 alternatives, they immediately knew what to do: Make a better mask.

Hosemann got on the phone, and discovered that the HMO’s doctors and supply managers wanted to know what makes an effective antiviral mask, and how they could verify whether the masks they found were actually any good. “It was helpful to learn what their needs were, and how we could fill in and help support their mission,” said Hosemann, who holds titles of faculty scientist in the Materials Sciences Division at Lawrence Berkeley National Laboratory (Berkeley Lab) and Ernest S. Kuh Chair in Engineering at UC Berkeley.