MINNEAPOLIS (WCCO) – As Minnesotan anxiously awaited the government. Tim Walz’s Announcement on Schools in the Fall, a new University of Minnesota study has analyzed how COVID-19 spreads indoors, especially in classrooms.
The experiment models the transmission of the virus through model aerosols that are expelled when people speak. Researchers measured how those aerosols land on nearby surfaces or are inhaled by another person.
With the help of eight asymptomatic COVID-19 carriers, the researchers modeled how the virus travels through the air in three indoor locations: an elevator, an orbit, and a supermarket.
Talking continuously after a 50-minute simulation run in class with an asymptomatic teacher, the researchers found that only 10% of their aerosols were filtered. Most particles attached to walls.
“Because it is very strong ventilation, we thought it would eject a lot of aerosols. But, 10% is a very small number, ”said Assistant Professor Soo Yang. “Ventilation creates many circulation zones called vortices, but aerosols rotate in this vortex. When they hit the wall, they join the wall. Because they are basically trapped in this vortex, and it is very difficult for them to reach the vent and actually go out. “
However, researchers were able to measure virus “hot” spots, or locations where aerosols were to collect. Their hope is being able to avoid these common areas with the right combination of ventilation and interior design. For example, in the classroom, the virus aerosol spreads less when the teacher is standing directly under the vent.
“This is the first quantitative risk assessment of the spatial variation of risks in indoor environments,” said Jiarong Hong, associate professor of mechanical engineering.
Insights can explain how indoor spaces are organized and disinfected. Researchers have recently collaborated with the Minnesota Orchestra to measure how the aerosols travel while musicians perform in the orchestra hall.