The CO2 meter makes a valuable contribution to the production of a healthy indoor climate, which is an important indicator of the possible virus concentration. The higher the proportion of poor quality air, the greater the spread and consequently the risk of infection by viruses. The AIRmonitor COMesh has a Swiss precision sensor with NDIR technology, the Sensirion SCD30, and provides reliable results on a long-term basis. The classification of air in accordance with DIN EN 13779 is carried out in high, medium, moderate and low quality levels, indicated with an easily understandable symbol. In the two lowest levels, a ventilation recommendation in the form of optical and acoustic signals is sent out. In addition, the user is permanently informed about time, temperature and humidity.This text is machine translated.