MINNEAPOLIS (WCCO) – As Minnesians eagerly await Chief Tim Walz’s report on schools in the fall, a new study from the University of Minnesota analyzed how COVID-19 is spreading indoors, especially in classrooms.
The experiment simulates an airborne virus through aerosols that are emitted by humans. The researchers measured how those aerosols landed on nearby surfaces or were inhaled by another person.
With the help of eight asymptomatic carriers of COVID-19, the researchers modeled how the virus traveled by air in three rooms: an elevator, a classroom, and a mall.
After modeling for 50 minutes in the classroom with an asymptomatic teacher, the researchers found that only 10% of their aerosols were filtered out. Most of the particles are attached to the walls.
“Because it’s very strong ventilation, we thought it would ventilate a lot of aerosols. However, 10 percent. There are a really small number, ”said Associate Professor Suo Yang. “Ventilation forms several zones of circulation called vortices, but aerosols rotate in this vortex. When they face the wall, they are attached to the wall. But because basically they are trapped in this vortex, and it is very difficult for them to reach the opening and actually get out. “
However, the researchers were able to measure “hot” areas of the virus or areas where aerosols tend to accumulate. They hope to avoid these common spaces by properly combining ventilation and interior design. For example, in the classroom, viral aerosols spread less when the teacher was standing directly under the opening.
“This is the first quantitative risk assessment related to the indoor environment,” said Jiarong Hong, associate professor of mechanical engineering.
Insight could help you know how the premises are tidied up and disinfected. Researchers recently collaborated with the Minnesota Orchestra to measure how aerosols travel and musicians perform in the Orchestra Hall.