What you need to know about face masks
The coronavirus pandemic has caused a critical shortage of face masks for health care professionals. But what about everyday people who want to protect themselves against COVID-19? After sending out conflicting messages early on, scientists and public health officials are now universally recommending that the public wear face coverings to slow the spread of the virus.
Here’s a quick look at what you need to know about face masks and coronavirus:
Q: Should I wear a mask?
A: With medical supplies running critically low, the World Health Organization and Centers for Disease Control and Prevention initially recommended that healthy people not wear face masks, unless it was specifically recommended by a health care professional.
However, on April 3, the CDC revised its guidelines, issuing new recommendations that advise Americans to voluntarily wear face coverings while in public to slow the spread of the novel coronavirus. The recommendation asked that people use basic “nonmedical, cloth” masks, including scarves and bandannas, to cover their noses and mouths when they leave home to go to the doctor, grocery store or other essential places.
Government officials still ask that medical masks in short supply, such as N95 respirators or surgical masks, be reserved for health care workers and first responders. Health officials also caution against relying solely on face coverings and said people should continue frequent handwashing and maintaining physical distance from others.
Q: What purpose do face masks serve?
A: The coronavirus is most commonly transmitted through respiratory droplets, such as when someone sneezes or coughs. A study done by the National Institutes of Health indicates that the virus that causes COVID-19 can remain suspended in the air for up to three hours.
Wearing a mask is one way to slow transmission.
There are two types of common masks: flat surgical masks, which are used in a health care setting to reduce the number of potential contaminants that mask wearers release into the immediate environment, protecting patients; and more advanced N95 respirators, which reduce wearers’ exposure to 95% of airborne particles, including small-particle aerosols and large droplets.
Masks, even cloth coverings, may also prevent the spread of infected droplets by asymptomatic individuals and reduce the likelihood that people will touch their faces.
Q: What is the proper way to wear masks?
A: WHO guidelines for effectively wearing a face mask are as follows:
Before putting on a mask, clean hands with alcohol-based hand sanitizer or soap and water.
Cover your mouth and nose with the mask and make sure there are no gaps between your face and the mask.
Avoid touching the mask while using it. If you do, clean your hands immediately.
Replace the mask with a new one as soon as it is damp and do not reuse or share masks.
To remove the mask, take it off from behind (do not touch the front of mask); discard immediately in a closed bin; and wash or sanitize your hands.
Q: Why is there a shortage of masks?
A: The panic that caused people to stockpile toilet paper and hand sanitizer as the pandemic spread also led to a global run on sales of face masks.
As a result, medical centers are facing severe shortages that are being attributed not just to high demand, but to disruptions in supply.
Most of the world’s surgical masks are made in China, where according to the Associated Press, the coronavirus outbreak has caused shortages of workers; and manufacturers say they are struggling to get enough raw materials to make the masks.
Q: Can I make my own mask?
A: Though fabric face masks are not as effective as N95 masks, according to the Food and Drug Administration, people are encouraged to wear them if venturing out in public. The CDC has recommended wearing fabric masks if maintaining the 6-foot social distancing radius is difficult, to avoid transmission of the virus or the potential contraction of the virus.
The CDC has updated its guidelines and is allowing health care workers to use bandannas, scarves or “homemade masks” to cover their faces “as a last resort” while treating COVID-19 patients.
Several templates for creating homemade masks are available online via a simple search.
Q: Is it safe to reuse a mask?
A: There are a number of risks associated with extended use and reuse of face masks. But due to the critical shortage, both the CDC and FDA have made allowances for cleaning and reusing N95 masks.
Extended use, the practice of wearing the same N95 respirator for repeated close contact with several patients without removing the respirator between encounters, is a practice preferred over reuse because it involves less touching.
If reusing a respirator, the CDC recommends the wearer consider use of a cleanable face shield over the N95 to reduce surface contamination. It also suggests sanitizing your hands before and after touching or adjusting the respirator.
The FDA has approved using aerosolized hydrogen peroxide to decontaminate masks without causing the material to deteriorate. The system allows respirators to be used up to 20 times, with a 2.5-hour decontamination process between each use.
Surgical masks are single-use only, as they present a risk of auto-contamination.
Cloth masks should be washed between each use, in hot water with regular detergent, and dried completely on a high heat setting. Always sanitize your hands after handling and do not touch your face.
Q: Can I donate my masks?
A: Yes, if they are the professional-grade kind sold in stores.
Almost all hospitals say they want only unused, unopened masks whose protection level is understood and guaranteed.
While well-intentioned, donations of hand-sewn masks will generally be turned away. Call ahead before you bring donations of hand-sewn masks to a hospital, and be prepared to hear that it will not accept them.
A detailed FAQ is available on SFChronicle.com about where to donate masks and other medical supplies. Chronicle staff writer Sarah Ravani
contributed to this report.