Corona: Murnauer researches for safe classrooms

How can schools be made as safe as possible in Corona times?

The question worries those responsible in municipalities, the debate is heated.

A group of high-ranking scientists around the Murnauer Prof. Dr.

Christian Schwarzbauer wants to provide answers through a pilot study.

Classrooms in Uffing and Murnau contribute data on the aerosol concentration in the air.

Uffing

- He has two preschool and elementary school children himself.

Prof. Dr. Christian Schwarzbauer was personally affected, and there was also worry and frustration: about the realization that "there are many institutes that could do something like this, but nothing happened". So the university professor from Murnau decided in March to act, free of charge and in his spare time, like other experts from renowned universities and research institutions whom he brought on board for the “Safe Classroom” pilot study. This has started under Schwarzbauer's direction in 40 classrooms: in Munich and in the districts of Garmisch-Partenkirchen - here data is collected in four rooms each of the primary school in Uffing and the Emanuel-von-Seidl primary school in Murnau -, Weilheim-Schongau and Bad Tölz -Wolfratshausen.From autumn the project is to be expanded to 120 classrooms in the greater Munich and Mainz area and to run over the school year. In this way, the researchers gain anonymized values ​​from practice, from a wide variety of situations, summer and winter. The schools receive the results and learn how great the benefits of different ventilation methods would be for them in real classroom operations. November should be an interim balance.

Air quality is measured and recorded in school over a long period of time

The air quality is measured and recorded in real school operations over a longer period of time, says Schwarzbauer, professor for medical technology and medical informatics at the University of Munich. On the project, which initially only runs in elementary schools, this cooperates with scientists from the TU and LMU Munich and the Max Planck Institute for Chemistry in Mainz. The researchers want to know how different ventilation concepts affect the air quality in classrooms and the risk of Covid-19 infection. How often do windows have to be opened to keep the aerosol concentration at a low level? Do indoor air purifiers make sense that Prime Minister Markus Söder (CSU) would like to see in every classroom in autumn? Or would retrofittable ventilation systems, such as the one developed by the Max Planck Institute in Mainz,the better alternative? According to Schwarzbauer, no more than 500 euros per room are to be charged for this in costs. The basic version of the systems consists of an exhaust fan and a tilted window. A comparative study by the Max Planck Institute shows that this system, which can still be optimized with extractor hoods over the tables, has better results than opening windows and is comparable to mobile room air purifiers. These have a positive effect on the situation. The question is, says Schwarzbauer, "how great is the benefit in practice".which can be optimized with extractor hoods over the tables, is better than opening a window and is comparable to mobile air purifiers. These have a positive effect on the situation. The question is, says Schwarzbauer, "how great is the benefit in practice".which can be optimized with extractor hoods over the tables, is better than opening a window and is comparable to mobile air purifiers. These have a positive effect on the situation. The question is, says Schwarzbauer, "how great is the benefit in practice".

The Uffing elementary school has so far been ventilated in the classic way

At the primary school in Uffing, Sabine Pecher has so far relied on the classic anti-aerosol method: cross ventilation every 20 minutes.

“But we don't have any experience as to whether that's enough,” says the Rector.

That is why she sees it as a blessing that her house can participate in the study, which gives her reliable facts.

Pecher thinks there is "insane pressure being built up" to buy air purifiers, but at the same time there is no information to make a decision.

Ventilation study: A socket-sized sensor can be found in four classrooms

Uffing's students don't notice anything more from the pilot project than the socket-sized sensor in the classroom. Schwarzbauer relies on technology from the Internet of Things. The sensor transmits measured parameters - carbon dioxide, humidity, temperature and the fact whether there are people in the room - to a receiver in the school's conference room, which forwards them to science via the cellular network. The experts calculate the aerosol concentration in the first step and the risk of infection in the second. "Our aim is to create a solid database so that decisions are made on a factual basis and not out of pressure," says Schwarzbauer, who now receives many inquiries from those responsible at the base who are unsure how to deal with schools . It appliesavoid renewed closings when the incidence increases.

Despite the importance: the researchers' budget is only half secured

Despite the immense importance and urgency of the study, Schwarzbauer and colleagues had to collect funds from foundations and independent sponsors because there was no government funding available at short notice.

“Amazing”, thinks the Murnau.

Around half of the necessary 60,000 euro budget for hardware has been covered so far.

The discussion about air purifiers for schools across Germany is likely to be a billion-dollar business.

The work of the researchers does not please all sides: One is, says Schwarzbauer, "also hostile".