Wash your hands for 20 seconds: Physics shows why

Researchers describe a simple model that captures the key mechanics of hand-washing, estimating the time scales on which particles, like viruses and bacteria, were removed. Particles are trapped on the rough surfaces of the hand in potential wells, as though they are at the bottom of a valley and the energy from the water flow must be high enough to get them up and out of the valley.

from Top Health News -- ScienceDaily https://ift.tt/37TFU3I