Masking the truth?

There is probably no subject that will incite a wellspring of emotional reaction during this pandemic than the one surrounding the importance of wearing a mask.  Of course, they work and if more people wore them, we would be done with this pandemic by now…right?  Before we rush to agree with what seems to be obvious, let us look at some interesting scientific facts. 

The SARS CoV 2 virus is .07 microns in size, but surgical masks and cotton masks allow the passage of material in size anywhere from 15 to 50 microns, respectively.  Therefore, the space between a surgical mask’s fibers is 150 times bigger than a SARS CoV 2 virus and about 450 times bigger in a cotton mask.  To further illustrate the size of a CoV 2 virus, you could line up 1000 SARS CoV 2 viruses along the width of a human hair.

Then there is the blockage of water droplets or aerosols.  Aerosols range in size from .7 microns to 10 microns.  Therefore, while most water droplets (10-15 microns) may be blocked initially from the front of the mask, water droplets and aerosols may easily pass through the sides of cotton masks into the ambient air. 

A surgical mask’s fibers fare a little better but the opening in the fibers is still 50 times bigger than the virus and 1.5 to 50 times bigger than water droplets.  In both cases, this is akin to using a chain-link fence to stop a gnat, a fly, or a golf ball from coming into your backyard.  N95 masks, are much more effective and can block 95% of particles as small as .3 microns. There is also an N99 mask which block 99% of all particles .3 microns or larger.  Both the N95 and N99 masks are really meant for health care workers who may be exposed to aerosol from patients with Covid-19 or other viruses.  Anyone who is serious about avoiding SARS CoV 2 would want to wear an N95 or N99 mask (it is really a low-level respirator) that is properly fitted for them.  However, be aware N95 masks...