Characterization of an airborne microbial community: A case study in the archive of the University of Coimbra, Portugal

► Indoor air microbial communities within the AUC were characterized. ► The most frequent fungal genera were Penicillium, Fusarium and Aspergillus. ► The microbial contamination of the AUC's air presented low values (<200 CFU/m3). ► Outdoor climatic conditions can influence microbial air population composition. ► Indoor air is likely to serve as a microbial contamination vector.