The authors undertook research on the proper strategy of operation of educational building with gravitational ventilation in historic city center with high concentration of particulate matter PM10 and PM 2.5. In this facility the momentary increase in carbon dioxide concentration is often very high, and at the same time health requirements regarding atmospheric aerosol should be absolutely met. That is why long-term measurements of PM concentration outside and inside, as well as carbon dioxide concentration inside were carried out. CO2 was used also as a tracer gas for measurement of air change intensity. The article presents the first results of these tests and a correlation that occurs between the external and internal concentration of particulate matter PM 10 and PM 2.5. Due to a significant filtration effect of the external building envelope and particle deposition a potential conflict between required gravitational ventilation intensity and internal air pollution with particulate matters was partially reduced.