Researchers from the University of Massachusetts Lowell and California Baptist University have revealed that wearing a used medical mask during a pandemic can be more dangerous than giving up completely. This is reported in an article published in the journal Physics of Fluids.
Masks affect airflow near the face, making people more susceptible to inhaling particles, and a dirty face mask cannot effectively filter out tiny droplets, according to scientists. While some believe that any mask is better than nothing, the protective equipment used is not effective against particles smaller than 2.5 micrometers.
The conclusion of experts is based on a computer model of a person with a three-layer surgical mask. The simulation determined how tiny droplets in the air were deposited on the face, upper respiratory tract, pharynx, or lungs. It turned out that a dirty mask significantly reduces the air flow rate, as a result of which its effectiveness is significantly reduced.