Acrylic dividers can help in some situations. But they can also make matters worse.
It makes good sense for plexiglass and similar shields to separate you from the sneezing or coughing in front of you that could contain the droplets that can carry the coronavirus, Sims told Beaumont.
So dividers can help in places like living rooms and grocery stores, he said.
“Have you ever coughed or sneezed in the car and you can’t take your hand off the wheel at this time?” ” he said. âYou know what your windshield looks like. Well, that’s what the plexiglass catches.
But if overused, those same barriers can also seal in contaminants in a small space, Sims said.
In a classroom, a more effective deterrent against the spread of the virus is to improve ventilation, he and others have said.
Gibraltar Superintendent Amy Conway said her district is removing acrylic partitions in classrooms this year. She said data from last school year showed little difference in COVID infection rates between districts like Gibraltar which have installed transparent shields and neighboring districts which have not. The study involving Georgian students also found that office barriers had little effect.
Gibraltar’s main mitigation measures will be “masking and cleaning,” Conway said.
Kevin Van Den Wymelenberg, director of the Institute for Health in the Built Environment at the University of Oregon, told New York Magazine that plexiglass would be helpful in stopping large droplets “if students are close and coughing.” , acting a bit like a sneeze guard at a salad bar. But if the children are already wearing masks, “there is little effect of the barrier”.
This is because there is some evidence that they can worsen classroom conditions, hampering the airflow of respiratory particles that a building ventilation system would remove and replace with fresh air.
âEveryone’s aerosols are going to get trapped and stuck there and build up, and they’ll eventually spill out beyond your own office,â said Linsey Marr, professor of civil and environmental engineering at Virginia Tech and authority on viral transmission. York Times.
Many schools have made improvements to ventilation systems or plan to use COVID school assistance funds to renovate sometimes decades-old heating, ventilation and air conditioning.
This is important because small particles can stay in the air for hours or days; good ventilation can help reduce the proportion of airborne contaminants.
The Georgia study found that coronavirus infections were 39% lower in schools that had improved ventilation systems than in schools that did not.
Even without costly HVAC upgrades, teachers can improve ventilation through “dilution” efforts – by opening doors and windows or using portable air purifiers and fans to dilute contaminants from the air in. air, experts said. Fans, for example, should be used to move potentially contaminated air outdoors, rather than just circulating it in small spaces.
âRemember to open the windows of school buses,â wrote Emily Somers, associate professor and epidemiologist at the University of Michigan, Bridge in an email.
Educators can also build affordable, do-it-yourself versions of purifiers that some tests have shown to work surprisingly effectively. They’re called the Corsi-Rosenthal boxes, Somers said, and require little more than a box fan, MERV 13 filters, and some time.
Schools should also consider moving activities outdoors when possible, especially activities in which higher levels of airborne viruses are expected to accumulate and spread, such as lunch, choir and the orchestra, Somers said.
In a review published in February in the Journal of Infectious Diseases, the authors found that the odds of transmission indoors are 18.7 times higher than outdoors.
Last school year, state health officials recommended that Michigan schools that offer in-person classes keep desks 6 feet apart to try to reduce the spread of COVID. This policy made it almost impossible for schools to have all students in classrooms at the same time.
But in a study published in March, researchers who looked at infection rates in 251 Massachusetts school districts with more than half a million students found no significant difference in the spread between districts that have adopted a social distancing of 6 feet versus 3 feet.
The CDC has updated its recommendations to reflect the change, but even that is superimposed on variables, said Dr. Peter Gulick, an infectious disease expert at Michigan State University.
A reduction in social distancing can be problematic in poorly ventilated areas or when vaccination rates are low, for example, he said. In these cases, weekly tests are advised.