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Education in Corona times: City of Bonn tests mobile air purifiers for schools

Education in Corona times : City of Bonn tests mobile air purifiers for schools

The city of Bonn wants to check again whether cross-ventilation is really possible at the schools and also in its daycare centers, or whether mobile air purification devices should be set up in addition. In the KJF daycare centers, ventilation units with Hepa filters 14 have already been in use since December.

For Oliver Überholtz, it is a small stage victory: For months, the father of a third-grader has been fighting for the city of Bonn to apply to the state for funding to purchase ventilation devices for the classrooms in Bonn's schools in connection with the Corona pandemic, and for the air purification devices already purchased by parents to be allowed to go into operation at his daughter's school, the Erich-Kästner-Schule in Kessenich.

Now the school and youth administration wants to examine all schools again, where no cross ventilation is possible by opposing windows and/or, where teachers are not convinced that the ventilation possibility in their classrooms offers sufficient protection. The city's daycare centers are also to be included in this review.

Until now, devices were not considered necessary

Until now, to the annoyance of Überholtz and other parents, the administration had always pointed out that there were sufficient ventilation options at the schools, that the devices were therefore not necessary and that there was therefore no money for their purchase by the state. But then the municipal crisis team dealt with the topic again last Wednesday in view of the newly emerged discussion about the use of air purification devices in schools and against the background of the open letter of the aerosol researchers," explained Carolin Krause, head of the family department, to the GA when asked.

The city of Bonn has so far not agreed to the use of such devices, since after consultation by the experts in the crisis team the fundamental advantages and disadvantages of an installation were not sufficiently clarified. Krause again reminded everyone of the inspection of all approximately 4000 school rooms in the past autumn, which had shown that only in four rooms of the Friedrich-List-Berufskolleg windows could not be opened. Air filter units were permanently installed there at that time. Krause continues: "For the installation of such devices to be effective, it is necessary, among other things, to carefully examine their positioning in the room, and the air flow they trigger must also be taken into account. According to the experts, simply placing them in the room does not produce the desired effect, so there is still no added value compared to the previous and proven measures - regular ventilation and covering the mouth and nose." And: "So far, there is not sufficient research evidence regarding the use of air purification devices in everyday school use," the department head continues to be skeptical.

She now announced that after the school rooms in question have been re-examined by an external expert, it will be determined whether, where, which and how many air purification devices should be installed in order to achieve the desired effect of extensive filtering of aerosols. The city would provide information on the timing of the examination as soon as an expert had been commissioned.

School and youth welfare committees welcome renewed examination

In the school and then in the youth welfare committees, members welcomed the fact that a renewed test is now to take place - then also in the daycare centers. "We were honestly quite surprised that this hasn't happened at all yet," said Imke Gilmer, deputy chairwoman of the Youth Welfare Committee. For Oliver Überholtz, the most important thing now is the test criteria. "Cross-ventilation means, after all, that you can open windows on opposite sides of the classroom". And to his knowledge, this is not possible at most schools. He has written to all the school governing bodies about this.

All 16 who had answered him so far had explained that this was not possible at their school. Überholtz points to studies by the University of the Federal Armed Forces in Munich and the Goethe University in Frankfurt, which confirmed that viruses can be filtered out via ventilation units with Hepa filter 14. "In any case, we as parents consider it an additional way to protect children and teachers in classrooms from infection," he said. The Federal Environmental Agency also sees ventilation equipment with the appropriate filters as a supplement, although in an expert report from this February, the agency cites "window ventilation as a priority measure."

Filters are used in KJF daycare centers

In its 27 daycare centers operated by the non-profit Evangelische Gesellschaft für Kind, Jugend und Familie (KJF) in Bonn and the Rhein-Sieg district, air purification devices with HEPA filters of class H14 have been running since December 2020, pedagogical director Melanie Rebmann-Rübo tells the GA. Following the publication of a study by aerosol researcher Professor Christian Kähler of the University of the Federal Armed Forces in Munich, the KJF ordered corresponding devices in September 2020 and installed them in the daycare centers starting in December. Larger devices would be in the hallway areas, while smaller, household-standard devices would be in operation in the group rooms.

The study, which Kähler published "on safe school operations in the SARS-CoV-2 pandemic," said, among other things, that air purifiers with H14 HEPA filters are by far the safest measure to protect the health of students and teachers in the fall and winter compared to ventilation and other techniques. "We've had fewer Corona cases since December than before," Rebmann-Rübo said. She could not provide concrete numbers. Rebmann-Rübo explained that the KJF sees the ventilation devices as an additional, effective measure to contain the pandemic in addition to AHA rules and interval ventilation. In addition, nearly all professionals at KJF facilities have also now been vaccinated against Corona, she added. (Original text: Lisa Inhoffen / Translation: Mareike Graepel)