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Even N95 masks are not fully sufficient. They typically block particles at 0.3 microns or larger, but coronaviruses tend to be smaller, around 0.1 - 0.3 micron
by SkyMarshal 7y ago
Even N95 masks are not fully sufficient. They typically block particles at 0.3 microns or larger, but coronaviruses tend to be smaller, around 0.1 - 0.3 microns.
You need an ASTM Level 2 or higher surgical mask to block coronavirus from completely penetrating the mask.
That said, any mask is better than no mask, first because it prevents you touching your mouth and nose with potentially infected hands, and second because coronavirus travels in water droplets which can be stopped by the mask from going straight into your mouth or nose.
- UncleOxidant 7y agoYes, the virus itself is small enough to get through, but typically the virus comes in a water droplet (as in being coughed or sneezed out) and those will be mostly stopped by an N95 mask.
- jeffmcmahan 7y agoHmm. Based on what I read, particles smaller than 0.3 microns have a widely "wandering" path of travel through the mask fibers on account of Brownian motion. My understanding was that 0.3 micron particles are the size that the N95 mask is least effective at blocking. Smaller particles are blocked more effectively, not less, until you get down to a scale so small that you pretty well exclude live biological material. Not my original source, but discusses the same thing: https://multimedia.3m.com/mws/media/376179O/nanotechnology-and-respirator-use.pdf https://multimedia.3m.com/mws/media/376179O/nanotechnology-a... This is to say, 95% filtration is the worst the mask will perform, with particles of any size, as it relates to coronavirus.
- hurrdurr2 7y agoThis is correct. Particles smaller in size than 0.3 microns will have HIGHER capture efficiency. This is similar for HEPA filtration as well.
- agumonkey 7y agocan't sub .3 microns particles get stuck in the fibers along the way even if they can pass the first (due to turbulent flow)?