The subject matter of this manuscript concerns the analysis and identification of microorganisms that pose a threat to human health and, in particular, mold fungi occurring in historical buildings. Surfaces infected by fungal spores pose a threat to the structure and the health of both visitors to historical buildings and professionals working in them. Research was undertaken to fill in the defects in building partitions with a supplementary layer of biochar in order to eliminate, or partially reduce, the possibility of contamination with and development of harmful mold fungi. In the designed cement mixture, biochar was used as a filler, the task of which was to eliminate the causes that lead to the development of harmful mold fungi. Microbiological analyses of the surface of walls and air in selected buildings were carried out before and after the application of supplementary biochar layers. The inhibitory properties of the material used against the presence and growth of mold fungi were observed. The average number of microorganisms isolated on the tested partitions decreased by between 70 and 100%. As a consequence, the use of this material significantly influenced the air quality of the rooms, which is important for protecting the health of people at work, as well as those visiting historical buildings.
Keywords: biochar; building mycology; eco-innovation; historical building; public health.