It’s a question or topic that gets thrown around here very often with little explanation or clarity.
This article will help explain what is happening at-scale with these particles and viruses.
Remember, the goal is to REDUCE THE INITITAL VIRAL LOAD which is thought to be related proportionally to the severity of disease i.e. mild cases vs. hospitalization or worse.
The particles in the study below (0.007 microns) that were filtered were 10 TIMES SMALLER than the coronavirus (.125 microns)