With implications for the transmission of diseases like COVID-19, researchers have found that ordinary conversation creates a conical ‘jet-like’ airflow that quickly carries a spray of tiny droplets from a speaker’s mouth across meters of interior space.
“People should recognize that they have an effect around them,” said Howard Stone, the Donald R. Dixon ’69 and Elizabeth W. Dixon Professor of Mechanical and Aerospace Engineering at Princeton University. “It’s not just around your head, it is at the scale of meters.”