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

  • Elevating Campus Maintenance: How Power Wash Drones are Transforming Educational Facilities

    As today’s campuses grow larger and more architecturally complex, keeping exteriors clean, safe, and inviting has never been tougher. Facilities leaders are under constant pressure to stretch budgets, meet safety standards, and support sustainability goals—all while tackling the stubborn challenge of exterior cleaning.

  • UNT Dallas Holds Ribbon-Cutting Ceremony for $100M STEM Building

    The University of North Texas at Dallas in Dallas, Texas, recently celebrated the opening of its new, $100-million STEM Building, according to local news. The ceremony on Dec. 2 preceded the first day of classes in the facility on Jan. 12, 2026.

  • Pittsburgh High School Upgrades Athletics Facilities’ Technology

    Plum Senior High School in Pittsburgh, Penn., recently partnered with South-Dakota-based Daktronics through the We’re All Mustangs Here Foundation to upgrade the technology in its athletics facilities, according to a news release. Daktronics designed, built, and installed new LED video displays and finished the project in time for the beginning of the 2025 high-school football season.

  • Texas State University Completes Stadium Renovations

    Texas State University in San Marcos, Texas, recently announced that it has completed a series of additions and renovations to its football stadium, according to a news release. Formerly known as the Bobcat Stadium End Zone Complex, the Johnny and Nathali Weisman Football Performance Center is an 85,000-square-foot expansion featuring hospitality spaces, banquet spaces, exterior concourses, and upgrades to the field house.

Digital Edition