People Are Sewing Face Masks for Medical Workers. Should They?

We’ve changed the title of this piece (from “Do Homemade Face Masks Actually Help Fight the Coronavirus?”) to more accurately reflect that we’re specifically addressing the use of homemade face masks for health-care workers. In April, the CDC began recommending that members of the general public cover their faces with non-medical masks to try to help protect others from the coronavirus (and yes, we have recommendations for cloth face masks). Because of this change, we’ve removed a paragraph from this article containing outdated advice from the agency (which said that only people who knew themselves to be sick—or who were caring for a person who was—should cover their faces). We’ve also removed a paragraph citing risk of autocontamination using cloth face coverings, as this is outweighed by the potential benefit of universal mask-wearing to slow the spread of coronavirus. We’re keeping an eye on medical guidance as it develops. If advice changes, we’ll update this piece accordingly.

As health-care workers struggle with a shortage of personal protective equipment in their fight against COVID-19, crafters are racing to sew cloth face masks for donation. It may seem unbelievable that the world’s wealthiest nation might need to resort to DIY face masks, but the Department of Health and Human Services estimates the US will go through 3.5 billion face masks fighting the coronavirus over the course of a year, and our national stockpile amounts to only 1% of that. So, should you dust off your sewing machine and start making masks for health care workers? We consulted the Centers for Disease Control and Prevention and a Minnesota hospital network to find out.

What does the research say about cloth masks’ effectiveness against viruses?

First things first, the recommended option for health-care workers treating patients with COVID-19 are N95 respirator masks, because with perfect use they catch at least 9% of particulates (as small as 0.3 micron) and, when properly fitted, form an airtight seal over the wearer’s nose and mouth. Simpler surgical masks are designed to stop splashes and droplets, and can prevent a sick person from spreading germs to others, but they do not create a seal and are nowhere near as effective as N95 masks at protecting health-care workers from viruses. Depending on the materials and construction, DIY cloth face masks may be even less protective than surgical masks. But under extreme circumstances, where face masks aren’t available, the CDC says homemade masks might be used, combined with other protective gear.

“Homemade face masks are not considered personal protective equipment [what healthcare professionals call PPEs], and should be an option only when there are absolutely no respirators or face masks left, and used with other protective equipment, such as face shields,” CDC spokesperson Arleen Porcell said in an email statement. “It’s important to note that this strategy is considered a last resort and does not adhere to the typical standards of care in the U.S., but acknowledges the hard realities on the ground.”

SARS-CoV-2 is so new that we don’t yet have direct studies to consult on the efficacy of different protective equipment. However, a 2015 study in Vietnam found that hospital health-care workers wearing cloth masks were far more likely to become infected with respiratory and flu-like illnesses than people wearing disposable surgical masks. Cloth masks stopped just 3% of particles, while medical masks stopped 56%. A 2013 study (PDF) by Cambridge University, which studied how aerosolized bacteria and viruses passed through DIY mask materials inserted into a testing device, indicates that only vacuum cleaner bags came close to matching surgical masks’ ability to block one type of virus; among cloth masks, tea towels blocked the highest percentage of the virus.

Why are some hospitals asking for homemade masks?

In part, some hospitals are asking for masks because they don’t want to turn away people who are seeking a way to help their communities’ battle against the coronavirus. Hospitals say they could use the masks for patients and health-care workers who have no chance of COVID-19 exposure, preserving more-protective equipment for higher-risk situations.

“We are meeting the desire of our community to assist and do something,” said Helen Strike, a nurse and COVID-19 system incident commander for Allina Health, a network of 13 hospitals and dozens of clinics in the Minneapolis area.

If Minnesota sees a surge in cases, Strike said the hospital network would consider using homemade masks for patients who do not have COVID-19. For example, according to Strike, someone who has a cough not related to COVID-19 could use a mask to contain any drops of saliva. Health-care workers in very low-risk situations could also use the masks in conjunction with a face shield or goggles. That would preserve N95 respirators for health-care workers who are dealing directly with COVID-19 cases.

“We and the CDC would agree that these are last resort measures,” Strike said. “We are hopeful that we never have to employ them for our general care that we deliver to any of our patients in the hospital.”

The CDC recently published a long list of recommendations for optimizing the supply of factory-made face masks, which should be used before turning to homemade masks or clothing, such as scarves. Other countries have seen good results from preserving more-effective masks for the most dangerous situations.

How are hospitals handling the homemade masks?

It’s unlikely that sewers are maintaining a sterile environment in their home, so Strike said Allina Health is cleaning the masks after donation. Beyond that, it isn’t clear. The CDC does not have guidelines for how to use homemade masks.

Surgical masks are intended for one-time use. If hospitals began to distribute homemade masks, they would need to decide how often patients and medical staff must switch out and wash their cloth masks. Another challenge is that surgical and cloth masks can provide a false sense of security, the World Health Organization noted, in a set of guidelines (PDF) published in January 2020.

“We in health care love to follow evidence-based practice,” Strike said. “We are accumulating all of the different ways people are using and cleaning those masks and how often they keep them on, and then developing our protocols out of those. We are not finished developing that yet.”

So, should you crank out homemade face masks for health care workers?

In the end, it’s up to you. No one knows whether the moment will arrive when hospitals decide to dip into their stockpiles of homemade masks. Production of N95 and surgical masks is ramping up. Meanwhile, we know that hospitals need factory-made N95, surgical masks, face shields, and gowns right now, so donate them if you have extras. You can also make a cash donation that will help hospitals buy the equipment they deem the most essential. Consider whether there is a way to use your time and resources to help someone with an immediate need, instead of a possible need.

If you do decide to make masks, it doesn’t hurt to support a local fabric shop, and remain wary about anyone making over-the-top claims about the need for DIY masks or advertising patterns “approved” by the CDC. There is no CDC-approved design for cloth masks; the agency provides only general guidance about fit. Instead, check whether your local hospital is requesting a specific design. In Tennessee, Vanderbilt University Medical Center wants two-sided cotton masks with or without elastic; in New Jersey, Atlantic Health System requests tightly woven cotton on one side and a softer fabric on the other.

You should also look for instructions on how to deliver the masks. Allina Health, for example, is collecting homemade cloth masks, plus factory-made protective gear, at 14 drive-through sites. If a hospital isn’t requesting homemade masks, don’t show up at the emergency room doors with a box of them. They may not have the time or resources to handle them.