We tested KN95 and KF94 masks sold online and at big box stores. Half of them didn’t offer the level of protection they’re supposed to. | CBC News: Marketplace

With coronavirus panic in full swing, surgical and N95 masks are flying off the shelves. But do they actually make a difference in protecting you against viruses? And can they protect you from other things like pollution, allergies, and mold? Wirecutter's research expert, Christina Colizza, walks you through exactly what these masks can and can't do for you. NOTE: Since shooting this video, the number of confirmed coronavirus cases in the US has increased from 12 to 15. Stay safe out there, and