What a face mask can do against COVID-19 and what it can’t
The federal government may recommend people wear masks in public, but the surgical and homemade masks gaining popularity offer only limited protection.
“I think there is a lot of benefit, but it’s really important that people understand what the benefit is, and also what the limitations are,” said Sarah Gordon, a Glenwood Springs native and consultant with Intrinsic Environment, Health & Safety.
According to Gordon, the greatest benefit to face masks isn’t that they keep out viruses, but that they stop people from touching their face as much.
Unlike the N-95 respirator used by health care professionals, which is in short supply, cloth masks and even surgical masks won’t keep out tiny viruses.
“The face masks don’t filter out the particle size of the virus. Viruses are tremendously tiny, and standard fabric is not going to filter out the virus,” Gordon said.
If someone lined up 1,000 microscopic COVID-19 virus particles end to end, it would be about the width of a human hair.
The novel coronavirus is the cause of the current pandemic, which breeds in the upper respiratory tract (nose, throat and mouth) and attacks the lungs.
While most facemasks won’t protect the wearer from contracting the disease, it can help an unwitting carrier of the virus from spreading it to others.
One of the ways wearing a mask could help slow the spread of disease, according to Gordon, is that people won’t touch their face as frequently.
“The benefit in wearing the facemask, for the general public, is that hopefully now that sneeze or sniffle or whatever it is, didn’t end up on their hands where they’re now going to touch a grocery cart, or a doorknob, or an elevator button,” Gordon said.
That is important since it’s possible someone might have the new coronavirus and spread it before showing symptoms.
And some who get it might not exhibit symptoms at all.
As many as 25 percent of people with COVID-19 might not have any symptoms, but could still spread the disease, CDC director Dr. Robert Redfield said Tuesday in an interview with a National Public Radio affiliate.
While wearing a mask might help, it is not a complete solution to avoiding COVID-19.
In Gordon’s work, which involves advising laboratories on protecting researchers from pathogens and other hazards, personal protective equipment is only part of how people stay safe.
“If you’re going to wear a homemade mask, you cannot let your guard down for all the other hygiene practices we all need to be doing,” Gordon said.
Those include frequent hand washing, avoiding going out in public, and maintaining 6 feet of distance.
Any viruses that are aerosolized in a sneeze or cough will get through the mask, Gordon said.
Even if the mask was made from a tightly weaved material, was sealed well to the face, it wouldn’t stop all particles from getting through.
“In a perfect scenario, you may have a mask that can slow down 60 percent of the viruses,” Gordon said.
Still, the masks can be beneficial because people won’t be touching their face as often.
The CDC so far has not advised the general public to wear facemasks. But it has recommended that people who are sick wear masks.
Others, including Colorado Sen. Michael Bennet, have begun urging the government to advise Americans to don homemade masks.
To gain all the benefits of wearing a homemade mask, using tightly-knit materials that isn’t frayed is important.
Some do-it-yourself mask patterns have an outer layer, an inner layer and a pocket for disposable filters — Gordon says putting a HEPA vacuum filter in a mask pocket could help, as long as it’s not too difficult to breath through it.
Another important factor in homemade masks is what’s called cheek fit, or how well the mask seals to the skin.
To ensure that air doesn’t flow between the mask and the skin, it should be as tight as possible. That’s why elastic bands aren’t ideal, since it can lose its tautness.
It’s also a good idea to sew wire in the mask where it goes over the nose, to squeeze it into a shape that fits the face.
Gordon advises people store masks in a plastic bag, until they can be washed with soap and water. Having two masks so that one can be laundered while another is available for use is a good idea, Gordon said.