The stability of fungal cells depends on both the environmental conditions and the state (vegetative cells, conidies, askospores) of their biological structures. An examination of the Kremlin's Amrory collection in Moscow established that the museum's storage conditions favored the destruction of fungal spore viability, both in areas where airborne contamination can occur and in areas of previous fungal damage. Mycological investigation of books damaged in a water accident showed a tenfold decrease in the number of viable fungi cells on the leather of book covers housed in those conditions for forty-one months. The observation of fungal populations associated with the accident made it possible to track the stability of the various fungi species. Mechanical cleaning of fungi and subsequent storage of artifacts in a controlled environment are proposed where well-regulated temperature and relative humidity conditions exist. -- CAL -- CAL