Poorly circulated room air raises potential exposure to contaminants by up to six times

Having good room ventilation to dilute and disperse indoor air pollutants has long been recognized, and with the COVID-19 pandemic its importance has become all the more heightened. But new experiments show that certain circumstances will result in poor mixing of room air, meaning airborne contaminants may not be effectively dispersed and removed by building level ventilation.

source https://www.sciencedaily.com/releases/2021/09/210922121908.htm