Relationship between indoor thermal comfort conditions and the Time Weighted Preservation Index (TWPI) in three Brazilian archives

There are many factors that affect paper degradation in archives, but air temperature and humidity under inadequate storage conditions are among the most important ones. Such inadequate conditions will trigger biological, chemical and physical processes that may enhance the degradation of papers. On the other hand, users of libraries and archives, where documents are stored, require adequate indoor conditions for carrying out diverse activities. In this paper we analyze the performance of archives with regard to paper and document storage conditions, also given in terms of the Time Weighted Preservation Index (TWPI), against overall comfort conditions, according to ISO 7730 and to the Building Bioclimatic Chart. For that purpose, five different settings were chosen, corresponding to indoor and outdoor conditions of three Brazilian archives, located in diverse climatic regions (Curitiba, 25°25'S 49°16'W, Belo Horizonte, 19°56'S 43°56'W and Rio de Janeiro, 22°50'S 43°10'W). The monitoring period comprehended 12 months, with a mid-term data collection. Results showed that there is a significant difference in storage conditions among different locations, even though there is a similarity in indoor thermal comfort conditions. A compromise solution should be sought between storage conditions and human thermal comfort parameters.