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Indoor air pollution in museums: prediction models and control strategies

Abstract The calculation of pollution mass balances is explained with reference to the modelling of indoor air quality in museums, and the implication of pollution deposition indoors and on museum objects is discussed. A short overview of the key pollutants in the museum environment and their effect on materials is given. Case studies, comparing old and new buildings, with and without air-filtration, in both urban and rural areas, suggest that pollution mainly infiltrates buildings via free air movement and that passive control measures may be sufficient to exclude outdoor pollutants. What this means for the level of pollutants generated indoors is not clear. Other studies have shown benefits from the use of active air-filtration, especially in urban areas with high pollution levels. The use of dosimeters rather than concentration measurements is now a focus in conservation research. Different approaches to setting acceptable limits for air pollution are briefly discussed, including the establishment of 'adverse effect levels'.