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Degradation of some cultural heritage monuments has been caused by interaction with the closest environment (micro-climate). Amount of separate compounds is very small and because of it, this fact becomes neglected. Time and temperature can induce their activity finally causing deterioration. In this category organic compounds can be interpreted as one of museum show - case element. This statement has been improved by testing glass objects and their suitable sensors (model glasses). Destructive activity of formaldehyde on historical glasses belonging to the XVIII-th c. objects with totally different compositions has been confirmed by carried out experiments. For historical material which is very limited, sensor glass method has been applied. Sensors are prepared on the base of results of chemical analyses of original glass chemical analyses and melted on laboratory scale (according to historical data). Induced corrosion for sensor supports knowledge about deterioration process in real micro-environmental conditions. The following testing methods were used: scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), optical interferometer (OI), inductively couple plasma (ICP).

The state of glass artifacts preserved in museums is strongly dependent on strictly local parameters. The deterioration of antique glass brought on by organic compound activity which will receive attention in this work has been studied on a sample of a 18th c. glass beaker belonging to the National Museum in Kraków. Measuring of the corrosion was carried out on an original, as well as on a model (or sensor) glass. The former -the remains of an 18th c. beaker -was borrowed from the Museum. The latter is a modern sample. Both samples were tested with a non-destructive method. Glass sensors, the chemical composition of which corresponded to the analyzed objects, were prepared. Their purpose was to facilitate the study of corrosion induced by different chemicals and altered physical conditions, previously proved in the museum real circumstances. The chemical structure of glass before and after the induced corrosion processes in formaldehyde and acetic acid solution was examined by the Fourier transform infrared and Raman spectroscopy. Moreover, complementary tests by scanning electron microscopy, energy dispersive microscopy, confocal microscopy were carried out as well. The corrosion processes were realized by means of shock temperature changes, as well as altering of relative humidity. Parallel corrosion processes under halogen lamp radiation were also induced. Measurements of induced corrosion pointed to the fact that deterioration of glass depends not only on the concentration of corroding media, but also on thermal shock. An experiment involving the lighting of an object by halogen lamp isolated a very important agent, which has significant influence on glass deterioration. The intensity of the induced corrosion resulted, in some cases, in glass volume corrosion as well. The obtained information can be useful for curators and conservators, as any resulting glass changes are responsible for further, this time irreversible, alterations.

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