The Science of Masks

Today, the Secretary of Health announced a statewide public health order requiring us to wear masks in public. So, how much do we really know about how much a cloth face covering can protect us from COVID-19? So much more than before!

couple wearing facemasks

Prior to this pandemic, there wasn’t a whole lot of research going on into the benefit of wearing cloth face coverings to prevent COVID-19, which, of course, we didn’t even know about until six months ago. Some researchers compared countries that promoted face masks as part of their early response to COVID-19 to countries, like the US, that did not. The countries that promoted face masks ended up with fewer cases than the countries that did not. Research is continuing, and we’re still learning more, but here’s what the science is telling us now:

  • COVID-19 be spread by people who do not know they have it (yet).
  • Having COVID-19 and not having any symptoms feels the same as feeling “healthy” or “normal.” The difference is, with COVID-19, you are contagious.
  • The virus that causes COVID-19 is principally spread by droplets that you exhale when you are normally breathing, as well as when you talking, singing, coughing or sneezing. These droplets can float in the air and infect people who are near you.
  • These droplets are more likely to reach other people if you are in an indoor space with poor ventilation, and within six feet of other people.
  • A cloth face covering helps you keep your breath, and those droplets, to yourself. You are even more likely to keep all those droplets to yourself if you are also standing six feet away from other people. And it works even better if the people around you are also wearing cloth face coverings.
  • Researchers reviewed the scientific literature looking at the effectiveness of surgical masks and cloth face coverings. They found that the masks and cloth face coverings were effective at preventing the spread of COVID-19 — if we wear them! The biggest limitation to their effectiveness was inconsistent mask use.

This means that people who feel healthy need to wear a cloth face covering in public places — especially indoors — and stay at least six feet away from other people.

And, no, wearing a cloth face covering is not at all likely to restrict your oxygen or make you breathe too much carbon dioxide or affect your immune system. If you feel dizzy or light headed, or have trouble breathing, sit down and remove your mask. If it continues, call 911.

Practice compassion. “Everyone shall wear a mask. Those who are not doing so are not showing their independence — they are only showing their indifference for the lives of others.” Sydney Morning Herald, February 3, 1919. Even before the modern research, people understood that wearing a mask is an act of compassion for others.

More information

Stay tuned to our blog for more information on how you can help stop the spread of COVID-19. Sign up to be notified whenever we post new articles.

Information in this blog changes rapidly. Check the state’s COVID-19 website for up-to-date and reliable info at

Answers to your questions or concerns about COVID-19 in Washington state may be found at our website. You can also contact our call center at
1–800–525–0127. Hours: 6 am-10 pm, seven days a week.

Department of Health call center: 1–800–525–0127, 6 a.m. to 10 p.m, seven days a week.

Please check our website for the most up-to-date info on Washington’s response to COVID-19 at

Medium is an open platform where 170 million readers come to find insightful and dynamic thinking. Here, expert and undiscovered voices alike dive into the heart of any topic and bring new ideas to the surface. Learn more

Follow the writers, publications, and topics that matter to you, and you’ll see them on your homepage and in your inbox. Explore

If you have a story to tell, knowledge to share, or a perspective to offer — welcome home. It’s easy and free to post your thinking on any topic. Write on Medium

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store