Conservazione preventiva e programmata del patrimonio culturale: orientarsi nel labirinto normativo per una prassi operativa di qualità

Preserving cultural heritage coincides with ensuring its conservation in the best environmental conditions, indoors or outdoors. While this concept, that of preventive and planned conservation, is now well known and made binding in Italy by Legislative Decree 42/2004 and Legislative Decree 36/2023, the operational techniques for implementing the best solutions to prevent damage to structures are less clear. The monitoring of thermo-hygrometric parameters and indoor air quality is a necessary tool for identifying possible damage mechanisms to materials due to environmental conditions. The assessment of the indoor microclimate in historic architecture has led to the development of an increasing number of regulations, guidelines, legislative acts and studies. It is possible to divide the regulatory and legislative documents into two groups: the first includes documents indicating predetermined ranges of parameters that most influence the relationship between cultural property and the conservation environment - in particular temperature and relative humidity; the second identifies the maintenance of the historical microclimate as the decisive element in avoiding damage to artworks or architectural elements, especially in the case of organic and hygroscopic materials. In order to arrive at a quality preventive and planned conservation project, suggestions are made in this study to increase the coordination between available standards and guidelines and facilitate their application with respect to some typical intervention scenarios.