Investigation of indoor environment quality in the storage areas of NTNU Gunnerus Library

Abstract

The NTNU Gunnerus Library is one of the most important cultural heritage libraries in the Nordic countries. The collections consist of a combination of materials with different levels of instabilities. In view of this fact, the target condition needs to be a compromise in order to maintain the required indoor environmental quality for the storage area. There are a number of consequences as a result of inadequate conditions of relative humidity, air temperature and air distribution. The main categories of degradation are biological, mechanical and chemical degradation. Literature states, that to minimize degradation of the cultural material stored at the library, it is important to maintain stable thermo-hygrometric values. The analysis of the measurements indicates a wide range of thermo-hygrometric values to which the storage area is exposed. Thus, the comfort zone, which is determined by the optimal condition including seasonal- and short-time fluctuation range, is often exceeded and the content of the storage is exposed to a substantial threat of damage.