The mechanical effect of moisturization on airborne COVID-19 transmission and its potential use as control technique

Arias, Francisco J.; De Las Heras, Salvador

Mounting evidence from scientific community seems to suggest that COVID-19 virus can potentially spread by airborne transmission. As a result, methods and techniques for preventing environmental contagious, such as ventilation or air filtration have been proposed. Here, it is investigated the effect of moisturization on airborne COVID-19 transmission from a mechanical point of view in which comparatively large water droplets promote the growth -by collision and coalescence, of suspended airborne COVID-19 and then accelerating its gravitational settling. Utilizing a classical raindrop collisional model from cloud science and the available experimental data an expression for the removal time of suspended airborne COVID-19 as function of the relative humidity was derived. The mechanical model is in good agreement with the recent reported experimental research in which high temperature and high relative humidity reduce COVID-19 contagious and then is a point in favor of the mechanic model of the effect of moisture in the COVID-19 airborne transmission. The results encourage further research on the deliberate moisturization of room air (by using ceiling mounted humidifiers) as a potential technique for control of airborne COVID-19 transmission.