Exhaled breath can provide a treasure trove of health information, offering a noninvasive window to both respiratory microenvironments and systemic physiological states. But collecting such data is a challenge.

In 2024, Caltech’s Wei Gao, professor of medical engineering, and members of his laboratory developed a prototype for a smart mask that uses clues from exhaled breath to monitor for a range of medical conditions, including respiratory ailments such as asthma and post-COVID-19 infections. Now, he and a team of researchers have updated the mask to make it more sustainable, to collect information for longer periods of time, and to evaluate additional health conditions and changes.