“Why Cloth Masks Might Not Be Enough as Omicron Spreads”

Repost from @wsj

“It will take 25 hours for an infectious dose of Covid-19 to transmit between people wearing non-fit-tested N95 respirators. If they’re using tightly sealed N95s-where only 1% of particles enter the facepiece-they will have 2,500 hours of protection.”