Face Masks and COVID-19

May 11, 2020

Face masks have become the symbol of the fight against COVID-19. Health officials and experts recommend that people wear masks when they are out in public to help slow the spread of the virus.

For the protection of its patients and employees, University Medical Center now requires people entering UMC facilities to wear their own face masks. (UMC is not able to provide masks because its supply is being used by its health-care professionals.)

Here’s a look at the different types of masks, how they work and the level of protection they can provide:

N95 masks offer the most protection but should be reserved for health-care workers. They derive their name from the fact that the mask can block at least 95% of tiny particles (0.3 microns) that are the hardest to capture. By comparison, an average human hair is about 70 to 100 microns wide. N95 masks include a nose piece that molds to the face, and some have exhalation valves on the front, which make it easier to breathe.
Medical masks filter as much as 60% to 80% of small particles and when worn properly can help prevent the spread of COVID-19 by catching droplets from the coughs and sneezes of others. Medical masks are often made of layers of breathable, paper-like synthetic fabric that has pleats to help it fit snugly around the face.
Homemade masks can sometimes protect the way a medical mask does, depending on the fabric used. A good homemade mask uses a material that is dense enough to capture viral particles, but breathable enough that it can be tolerated. Heavy cotton t-shirt and flannel fabric, or a tightly woven dish towel, are the types of materials recommended. Materials with a higher thread count (allowing very little light to filter through) offer the best protection. Homemade masks should include at least two layers of material, have secure straps and come up over the nose and below the chin.
Homemade masks with filters have a pocket sewn inside to hold an additional filter. Coffee filters and paper towels placed inside the pocket have been used as filters.

Masks have to be worn property to be effective, health experts said. Masks should fit snugly from the top of the nose to below the chin, with no gaps. While no mask is 100% effective, it can help keep you and others safe, when combined with social distancing and regular hand washing, experts said.