Coronavirus protection in schools: Airing rooms for five minutes, every 20 minutes | Umweltbundesamt

Dirk Messner said, “Where many people are together in a small space, the virus can accumulate in the air. Ventilation is the simplest and most effective way to remove viruses from the air in classrooms. Our guidelines are designed to help schools ventilate properly and as effectively as possible. Of course, airing does not provide one hundred percent protection. Other hygiene measures in accordance with the specifications of the federal states are and remain important and should be observed in everyday school life".

Stefanie Hubig, KMK President and Education Minister of Rhineland-Palatinate said, "The handbook offers guidance for all those involved in schools and I am pleased that we can now make it available to all the Länder, school authorities and schools. The German Environment Agency's recommendations on air exchange and efficient ventilation contain brief and precise information on why, when and how to ventilate - and also refer to frequently asked questions. With proper ventilation, we make a decisive and effective contribution to reducing the risk of infection from aerosols containing viruses in schools."

In addition to airing every 20 minutes, ventilation should also be provided during each class break. All windows should be opened wide for airing (airing at intervals). Opening only one window or putting windows on tilt is not enough. Cross ventilation is ideal if windows on opposite sides can be opened. In both cases, the temperature in the room drops only a few degrees. People who are quick to feel cold can slip on a jumper for a short time. After closing the windows, the room temperature rises again quickly.

With simple ventilation, CO2, moisture and chemical substances are effectively removed from the air in addition to aerosols potentially containing viruses. CO2 can make you tired if the indoor concentration is too high and can lead to a lack of concentration. Too much moisture favours mould formation. Mobile air purifiers can neither remove CO2 nor humidity. In addition, they are usually not able to quickly and reliably remove viruses from the indoor air, especially in crowded classrooms. This is why mobile air purifiers are not suitable as a replacement, but at best as a supplement to active ventilation. If rooms cannot be ventilated, they are not suitable for classroom use from the point of view of interior hygiene.