Impact of air pollutants on modern heritage

Very few scientific studies have been dedicated to the impact of multipollutants on 20th-century built heritage. The effect of the impact of gaseous pollutants and aerosols on cement mortars in urban areas, especially the formation of black crusts, is still not well documented, making this issue a challenging area of research. The present work focuses on the evaluation of the impact of air multipollutants on the Casa Galleria Vichi, a modern concrete building dated 1911, located in the center of Florence (Italy). In order to investigate the surface damage induced by air multipollutants, samples of deterioration layers (crusts) and underlying material were collected and analysed. The results obtained from the experimental activity performed on the damage layers indicate that gypsum, due to the deposition of sulphur atmospheric compounds, is the main damage product. Furthermore the particulate matter found embedded in the gypsum matrix, shows that oil fossil fuel combustion is the main cause of building surface blackening.