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

  • Cal Poly Humboldt Starts Construction on Healthcare Education Hub

    California State Polytechnic University, Humboldt in Arcata, Calif., recently announced that work has begun on a renovation project that will turn the Stewart Building into a new Healthcare Education Hub, according to a news release. The university is partnering with Sundt Construction Inc. for construction services.

  • Moline-Coal Valley School District to Consolidate Two Schools into New Facility

    The Moline-Coal Valley School District in Moline, Ill., recently broke ground on a new elementary school that will consolidate the students and staff from two existing schools, according to local news. Robert Ontiveros Elementary School will serve as the new home for Lincoln-Irving Elementary School and Willard Elementary School.

  • S4L Announces 2026 Education Design Showcase Winners

    Spaces4Learning is thrilled to announce the winners of the 2026 Education Design Showcase! Now in its 27th year, the annual awards program honors innovative solutions in planning, design, architecture, and construction across K–12 and higher education.

  • University of Oklahoma Announces New Campus Master Plan

    The University of Oklahoma in Norman, Okla., recently announced that it will soon launch a new, comprehensive Campus Master Plan to guide the campus’ physical development during the next decade, according to a news release.