The future belongs to children and they need education to shape the future with foresight and intention. Children therefore have the right to education, according to Article 29 of the UN Convention on the Rights of the Child. However, professional education is not everything, because children must also experience their strengths and weaknesses together and educate each other to be responsible and considerate people, so that they become socially valuable personalities. Only in this way can they shape the future in a peaceful and humane way. Therefore, attending school is essential. However, children also have the right to protection and care by their parents and the state, because the welfare of the child must also be given priority in accordance with Article 3 of the UN Convention on the Rights of the Child. The question is therefore how schooling in community schools can be realized during the SARS-CoV-2 pandemic without exposing children to an unnecessary risk of infection. It is not only about the children, because if the children are at risk, then so are their parents and grandparents and ultimately society as a whole. There are numerous concepts that promise safety in schools during the pandemic. When selecting concepts, the costs must of course be weighed against the benefits. People rightly expect an efficient use of resources. This means that either the set goal is achieved with the least possible resources or that the available resources are used to achieve the greatest possible approximation to the goal. In addition to the financial resources, however, the long-term consequences for the state, the economy, the population and the environment under the pressure of the pandemic must also be taken into account. Social cohesion and democracy must not be jeopardized either. Various protection concepts are currently under discussion. Often the advantages are overstated and the disadvantages concealed. Furthermore, some arguments are based on assumptions that are not true. The aim of this study is to provide a comparative assessment of the main protection concepts and to demonstrate, with the help of experimental analyses, the extent to which the protection concepts are effective. We will show that a comparatively high level of safety against infection in classrooms can be technically ensured without exposing children to masks. At the same time, the protection concept makes economic sense and the burden on the environment is comparatively low, so that infection prevention and climate protection do not have to be weighed against each other, because infection prevention and climate protection are political and social goals that have to be achieved together.

The SARS-CoV-2 pandemic is limiting both the private and public lives of many people around the world. It is now considered certain that SARS-CoV-2 is transmitted via droplets, smear infection, and aerosol particles. While simple masks, spacing, and hand hygiene significantly reduce the risk of infection via the first two routes mentioned, the risk from aerosol particles remains. These small particles move with the air in the room and spread unhindered throughout it. To reduce the risk of infection from viruses present in aerosol particles, the following options exist. First, good respiratory masks can be worn to reduce the viral load in the inhaled air. Another option is to make the viruses harmless (e.g., by UV light). A third option is to reduce the viral load in the room by bringing in virus-free air and moving contaminated air out or cleaning the air in the room. To investigate how well virus load reduction via ventilation works in a real lecture room, measurements were carried out at the Universität der Bundeswehr München (University of the Federal Armed Forces Munich). The lecture room holds a maximum of approx. 90 people and has a ventilation system as well as 2 windows that can be opened. In the absence of a ventilation system in a comparable room, the effectiveness of a room air cleaner was also investigated.