What’s the best material for a homemade coronavirus mask? Here’s what experts say

Last week, the Centers for Disease Control and Prevention recommended that Americans wear non-medical masks in public to help prevent the spread of coronavirus, reversing an earlier directive against it.

To help preserve available masks for hospital workers, the CDC asked people to make their own cloth face coverings, even releasing their own guidelines and tutorials.

Other mask how-to’s quickly spread across the internet, and some are wondering what materials are going to provide the most protection.

While the CDC says materials like bandannas and t-shirts are effective at keeping particles from passing from a person through the mask and out into the world, experts say some household items can also be effective at keeping particles from passing through the mask and to the wearer.

Density is the name of the game.

Recent tests found that vacuum cleaner bags, HEPA furnace filters, fabric similar to flannel and layers of 600 thread-count pillow cases scored high in filtering out incoming particles, the New York Times reported. Layered coffee filters also scored relatively well.

Stanford Medical School had similar findings adapted from a 2013 study that assessed how well homemade masks would protect people during an influenza pandemic.

The study found that vacuum cleaner bags, tea towels and cotton mix fabric scored high when it comes to stopping viral particles, with antimicrobial pillow cases, linen, cotton t-shirts scoring mid-range and pillowcases, silk and scarves scoring lowest.

While vacuum cleaner bags scored high, Stanford’s research indicted that they can be difficult to breath through.

Not sure if a fabric will be effective? Hold it up to the light, Dr. Scott Segal, chairman of anesthesiology at Wake Forest Baptist Health, told the Times.

“If light passes really easily through the fibers and you can almost see the fibers, it’s not a good fabric,” he said. “If it’s a denser weave of thicker material and light doesn’t pass through it as much, that’s the material you want to use.”

No matter what material you choose to use, it’s important to follow the CDC’s instructions on how your mask should fit.

The agency says face coverings should:

• “Fit snugly but comfortably against the side of the face”

• “Be secured with ties or ear loops”
  
  
• “Include multiple layers of fabric”
  
  
• “Allow for breathing without restriction”
  
  
• “Be able to be laundered and machine dried without damage or change to shape”

This story was originally published April 7, 2020 at 3:23 PM with the headline "What’s the best material for a homemade coronavirus mask? Here’s what experts say."