Microns, also called Micrometers, are a small units of measure, commonly abbreviated with μm. Human hair typically ranges from 30 to 100 microns, with 80 microns considered the most common size. The novel Coronavirus (Covid19), measures about 125 nanometers, or 0.125 microns, and is slightly larger than the common flu virus (100 nanometers or 0.125 microns). The smallest tiny item we can see with the naked eye is pollen, which is about 40-60 microns in size. Our limit of visibility drops around 40-60 microns. VOCs or volatile organic compounds are less than 3 microns in size, roughly half the size of a red blood cell. HEPA filters and N95 masks are effective to about 0.3 microns. The below chart also shows relative comparative sizes of of common items, from a penny (19,053 microns) to a drizzle raindrop (200 micron sizes). 1 centimeter equals 10,000 microns. When it comes to air filtration, particle spray application, micron sizes matter. When a disinfectant is used, the proper dwell time is needed. Using an inappropriate applicator tool that creates such a fine mist that the droplet size can bounce off surfaces or evaporate too quickly, causing a failure in chemical effectiveness.