N95 masks and how they work

Question

N95 masks and how they work

In: Technology

Answer 1

Filters work not by sifting out particles larger than the spaces between fibers, but by stirring up air so that particles collide with, and stick to, the filter media. The holes are larger than the particles being captured so that air goes through more easily. The key for making an effective filter is to have as many very thin fibers as possible that are sticky to the particles you want to capture.

N95 masks are optimized for water-based droplets, so the stickyness of the fibers applies to water-based particles, like the droplets that viruses may be suspended in.