COVID-19, Protect Yourself

Advice on Masks

By: Namuun Clifford
Nurse Practitioner practicing in California
20 · Feb · 2020
Photograph by: Suniko Bazargarid

Medical masks do not protect against air pollution

Regular surgical face masks do not protect against air pollution. They are designed to prevent respiratory droplets from transferring to others when you cough or sneeze and prevent you from touching your mouth and nose. They do not offer an airtight fit around your nose and mouth, allowing air to come in from the sides when you inhale, offering no protection against the tiny pollutant particles such as “PM2.5” and PM 10” circulating in the air.  

The only masks that can effectively protect against these harmful pollutants are the N95 or N99 masks. “N95” means the mask is capable of filtering out at least 95% of the particles in the air, while the N99 mask is able to filter out 99% of particles if worn correctly. 

In a highly polluted environment such as in UB, the best way to protect yourself from both air pollution and risk of respiratory infections would be to wear the N95 masks outdoors and a surgical face mask indoors if you are sick with a cough.

Woman wearing N95 mask
N95 Mask

It’s important to remember the use of a mask alone does not provide an adequate level of protection and must be used in conjunction with general hygiene practices. People with fever, cough, or shortness of breath should always wear a medical face mask to protect others. 

If medical face masks are worn, they should be used and disposed of appropriately:

  • Masks should be placed carefully to cover the mouth and nose and tie securely to minimize any gaps between the face and the mask. 
  • While in use, avoid touching the mask.
  • Remove the mask by removing the lace from behind, do not touch the front of the mask.
  • After removal or whenever you inadvertently touch a used mask, clean hands by using an alcohol-based hand rub or soap and water if visibly soiled.
  • Replace masks with a new clean, dry mask as soon as they become damp/humid.
  • Do not reuse single-use masks.
  • Discard single-use masks after each use and dispose of them immediately upon removal.
  • Cloth masks provide no protection against pathogens.

The colored side of the mask should always face outward.

Translated to Mongolian by K. Gantumur

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