The research, published in the journal Physics of Fluids, noted that the number of people using face shields as a substitute for face masks has been increasing in schools, universities, restaurants, and service businesses.
However, the scientists, including those from Fukuoka University in Japan, said sneezes produce a fluid phenomenon known as vortex rings that can capture microscopic particles and pass through the shield’s barrier.
“A vortex ring is a donut-shaped vortex that is generated by an instantaneous ejection of fluid from a circular orifice. his resembles bubble rings made by dolphins,” explained study co-author Fujio Akagi from Fukuoka University.
In the study, the scientists assessed what happens when a face shield wearer is exposed to