August 26, 2020

Wearing a mask works only if worn properly

WEST LAFAYETTE, Ind. — Many people consider wearing a mask to be cumbersome, but people have relied on them before during pandemics.

A Purdue University nursing professor says looking to the past – as well as additional knowledge of medicine and technology – can help people through the current COVID-19 pandemic.

Joy Pieper, a clinical assistant professor of nursing in Purdue’s College of Health and Human Sciences, teaches two courses on health care history and wartime influences on health care. As the COVID-19 pandemic was spreading in the spring, Pieper and Rebecca Johnson taught about the influenza outbreak of 1918 and the protective measures communities took – including wearing masks – to reduce the spread of disease.

      The current surging spread of COVID-19 has put a high level of attention on masks. Pieper, who has expertise as a surgical nurse and has worked on infection control and patient safety initiatives, provides four tips on proper mask usage:

  • Pick out a mask that is easy to wear. Pieper says studies are suggesting the higher the thread count in masks, the better, and another layer helps too. “Think of the Swiss cheese principle: You are trying to block anything from getting through consecutive holes. The more layers, the better,” she says.

For the general public, Pieper does not recommend wearing a mask with valves. “Masks with certain valves that can filter are really designed for use by workers in cleaning and construction fields to filter out dust and other materials. They don’t prevent the spread of infection because the valve only filters air coming into the mask and not what is exhaled.”

  • Proper mask placement and removal. When removing a mask, be sure to fold it in half so the outer part of the mask stays contained when stored in a pocket or plastic bag.

“You should always clean your hands after you remove the mask,” she says. “If you think about it, you are touching something you have put in place to literally intercept germs, so it contains potentially infectious material that you now have on your hands and could spread through touch.”

  • Cover both the mouth and nose. “Wearing your mask to cover only your mouth is not helping anyone, including you,” Pieper says. “Both your nose and mouth need to be covered because you breathe out of both. The mask is meant to cover all air exchanges, not just a cough.”
  • Keep your mask dry and clean it after every use. Pieper says wet fabric can transfer germs more easily than dry, so it’s advisable to carry replacement masks.

The mask or masks you wear during a day should be laundered before use again, so it is a good idea to own a couple different ones so you do not have to do laundry every day,” Pieper says. “They can be cleaned by machine or by hand according to the type of fabric.

About Purdue University

Purdue University is a top public research institution developing practical solutions to today’s toughest challenges. Ranked the No. 6 Most Innovative University in the United States by U.S. News & World Report, Purdue delivers world-changing research and out-of-this-world discovery. Committed to hands-on and online, real-world learning, Purdue offers a transformative education to all. Committed to affordability and accessibility, Purdue has frozen tuition and most fees at 2012-13 levels, enabling more students than ever to graduate debt-free. See how Purdue never stops in the persistent pursuit of the next giant leap at

Writer, media contact: Matthew Oates, 765-586-7496 (cell),, @mo_oates

Source: Joy Pieper,

Related: How to make sure you’re wearing your mask right

Journalists visiting campus: Journalists should follow Protect Purdue protocols and the following guidelines:

  • Campus is open, but the number of people in spaces may be limited. We will be as accommodating as possible, but you may be asked to step out or report from another location.
  • To enable access, particularly to campus buildings, we recommend you contact the Purdue News Service media contact listed on the release to let them know the nature of the visit and where you will be visiting. A News Service representative can facilitate safe access and may escort you on campus.
  • Correctly wear face masks inside any campus building, and correctly wear face masks outdoors when social distancing of at least six feet is not possible.


Note to journalists: An image of a person wearing a mask is available on Google Drive. Joy Pieper is available for phone and web-based conference interviews. Journalists visiting campus should follow visitor health guidelines.

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