Hi! I read that n95 filters 95% of particles of around 0.3 micron, n99 around 99.3% ,surgical masks are less efficient than these & cloth masks are not considered as efficient as above masks. Further, I also read that the largest size of 0.14 micron which is much less than 0.3 micron that above masks can filter. So, what mask one should wear, if none of them can restrict 0.14 micron covid-19 particle. Moreover, it is said this virus spreads from droplet, so, when one coughs or sneezes, does this virus remains attached to the droplet or separate it from droplet? If it remains attached to droplet, then, perhaps the size (diameter) of droplet should matter that the size (diameter) of virus. Please clarify. If it is true that no mask can restrict entry of cavity-19 particle, then, mask must be accompanied with eyeglass & face shield or with face shield alone. Please guide, it is so confusing.