As wildfires scorch Canada and smoke blankets the United States from Minnesota to New England and south to Florida, millions of people are under air-quality alerts. Face masks — the same kind used in the COVID-19 pandemic — can help protect people from dangerously polluted air, say health experts. But choose a good quality mask, they caution. “N95 masks are the type of face covering protection that I would recommend for somebody who is outside during the air pollution caused by wildfires,” Marina Vance, PhD, an assistant professor in the environmental engineering program at the University of Colorado, Boulder, told...