At Western University in Ontario, researchers have analyzed the propagation of particles when a person coughs. Eric Savory, Professor at the Faculty of Mechanical and Materials Engineering, concluded that at a 2.5 meter distance, we still find 10% of the droplets emitted.
This research is modelling the physical movement of particles, without taking into account the biology of the virus.
Philippe Mercure. La contagion pourrait se faire au-delà de deux mètres. La Presse. April 23, 2020.