It has come to light, in a recent study that, droplets from a cough or a sneeze without a mask can travel farther and last longer in humid, cold climates than in hot according to a study on droplet physics by a team of international engineers. Researchers incorporated the understanding of environmental factors like the climate, the rains, etc. on the drop spread into a new mathematical model that can be used to predict the spread of the virus including COVID-19.
This model is the first to be based on chemical reactions called collision rate theory, which looks at the contact and collision rates of a droplet cloud exhaled by an infected person with healthy people. Their work connects population i.e. the human contact with their micro-scale droplet physics and the results on how far and fast droplets spread, and how long they last. In this study, it was found that, depending on weather conditions, some respiratory droplets could travel between 8 feet and 13 feet away from their source before evaporating, without even accounting for wind. This suggests that without masks, six feet of social distance may not be enough to keep one person’s exhaled particles from reaching someone else.
This study has spread hope that this detailed model for the rate of infection spread will help inform the public health policies and can be used in the future to better understand the spreading virus.