When To Test

Who is That Masked Man?

Wearing a mask helps protect you from COVID-19, even if you’re the only person in the crowd who’s wearing one.

Liz Ruark
Man on subway, wearing a mask

Mask requirements are fading into pandemic history. But when COVID-19 levels are high in my area, I still jam a KN95 into my pocket before leaving the house. You may wonder: Is wearing a mask still worth it if you’re the only one doing it?

Yup, it sure is. Here’s how we know.

All different kinds of research — from modeling studies to laboratory experiments to real-world studies in schools and across states — have shown that masking helps prevent the virus from spreading. And while those lab experiments show that having everyone masked is the most effective way to prevent spread, they also show that wearing a mask helps protect the person who wears it. And the better the mask, the more protection you get.

How much protection? Depends on two things:

  • Filter: How well the mask filters out the tiny bits of moisture that carry the virus.

  • Fit: How snugly the mask fits on your face.

Want to know how your mask ranks? Check this infographic. Need to see the numbers? Here you go — the studies behind them are here, here, here, and here:

  • Cotton mask: 30 - 56% less likely to be infected than if you don’t wear a mask

  • Surgical mask: Up to 66% (best if worn knotted and tucked)

  • KN95 or KF95 mask: Up to 85%

  • N95: Up to 95%

So if you’re concerned about getting COVID-19, mask up. Will it guarantee that you won’t get COVID-19? Nope. But it’s a heck of a lot better than nothing.