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

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

  • Deferred Maintenance Issues Growing at Universities, Gordian Reports

    U.S. colleges and universities are falling increasingly behind on facilities maintenance and repair, according to Gordian’s 13th annual State of Facilities in Higher Education report. The deferred capital renewal burden has reached $156 per gross square foot, an 8% increase over the previous year.

  • Homewood-Flossmoor High School NetZero Addition

    Homewood-Flossmoor High School NetZero Addition

    Established in 1999, the Education Design Showcase is a vehicle for showing off innovative — yet practical — solutions in planning, design, architecture, and construction. The Homewood-Flossmoor High School NetZero Addition has been recognized with an EDS 2026 Project of Distinction award in the category of New Construction.

  • Barbara Vick Western Branch

    Barbara Vick Western Branch

    Established in 1999, the Education Design Showcase is a vehicle for showing off innovative — yet practical — solutions in planning, design, architecture, and construction. The Barbara Vick Western Branch has been recognized with an EDS 2026 Grand Prize award in the category of Renovation.

  • Phoenix School District Breaks Ground on New Prep Academy

    The Creighton Elementary School District near Phoenix, Ariz., recently broke ground on a campus replacement for Biltmore Preparatory Academy, according to a news release. The new space will allow the school to expand its enrollment by 50 percent for K–8 students and accommodate modern, collaborative learning styles.