Skip to main content
Add as a preferred source on Google

Classroom Purifier Cuts Infection Risks in Half—Same as Opening Windows

  • By Dian Schaffhauser
  • 03/08/21

A study in two South Korean high schools found that window ventilation reduced the risk of COVID-19 infection by 55%, while the use of an air purifier shrank the risk by 50%. The combination of the two dropped the risk by nearly three-quarters (73%). Researchers from the Infrastructure Safety department at the Korea Institute of Civil Engineering and Building Technology (KICT) said the use of the air-purifying device worked best when it was placed in the middle of the room, which was sized to hold about 25 students.

The study ran several rounds in which the performance of various antiviral and antibacterial air purifiers was tested in an actual classroom. Virus-like salt microparticles were released into the air as aerosols, and the researchers measured the concentration levels in succession in the center and at the edge of the room during each round to simulate the presence of an infectious student.

For a final round, the researchers worked with a specific air purifier: the AiroDoctor WAD-M20. The testing, which ran over the course of several days, assumed that students didn't move about the space and maintained distances from each other.

The AiroDoctor is a $4,000, free-standing device about the size of a 13-gallon garbage can. According to coverage of the study, students weren't bothered by noise from the machine.

"We are very pleased about the groundbreaking results from South Korea," said Carsten Hermann, managing director of ScreenSource GmbH, which produces the machine, in a press release. "We trust that the relevant authorities nationally and internationally will take notice of such important studies. After all, the globally unique filter technology of the AiroDoctor can make an important contribution in a long-term strategy against SARS-CoV-2."

About the Author

Dian Schaffhauser is a former senior contributing editor for 1105 Media's education publications THE Journal, Campus Technology and Spaces4Learning.

Featured

  • Doerr School of Sustainability Accelerator

    From Concrete Warehouse to Innovation Hub: Accelerating Sustainability at Stanford

    The transformation of a once windowless, concrete publishing warehouse into a sun-drenched center for global innovation began with a single, fundamental challenge: how to turn an industrial storage shell into a space built for human connection.

  • Round Rock ISD Completes New Early College High School

    Round Rock ISD near Austin, Texas, recently announced that construction is complete on a new, 46,500-square-foot campus for Early College High School, according to a news release. The new facility will allow the school’s students and staff to move from portables into a permanent building and increase its enrollment to 500.

  • Girl Sitting at Library Desk, Using Laptop

    How Campus Design Shapes the Finals Week Experience

    Academic performance is not just about preparation. It is closely tied to how students manage stress, maintain their energy, and shift between work and recovery modes. Much of that is influenced, directly or indirectly, by design.

  • Academy of Classical Education Breaks Ground in Louisiana

    Charter Schools USA (CSUSA) recently announced the groundbreaking of a new public charter school in Covington, La., according to a news release. The Academy of Classical Education at Covington will enroll students in grades K–8 and is scheduled for completion in August 2026, just in time for the new school year.