Influences des agents polluants en suspension atmospherique sur des pierres selectionnees, traitees et non traitees : Effects of air pollutants on selected prepared and not prepared stones

: Reichert, T.F.; Bräuning, A.; Karotke, E.

Abstract
The main goal of the investigation is to answer the question of a possible concentration or enrichment of pollutant caused products behind the soaked zone of a protected stone sample and to compare the effects of the air pollutants on unprotected specimen with the effects on the protected specimen. For this reason side on sealed samples were prepared (soaked) by the "Institut für Bauforschung (IBAC, Aachen)" with preservation materials and were exposured in special wethering and fumigation chambers by the Fraunhofer-Institut für Chemische Technologie (ICT, Pfinztal). For the fumigation the pollutants sulfur dioxide (5000 myg/cbm), nitrogen dioxide (5000 mym/cbm) and ozone (2500 myg/cbm) are used. After the periods of exposure the samples will be cleaved. On one half of the stone the penetration depth of the protection layer or the impregnation will be tested and the other half will be investigated for the concentration of pollutants. The mineralogical investigations will be done by the Institut für Mineralogie of the University of Karlsruhe.