The buffering effect of a paper-based storage enclosure made from functional materials for preventive conservation

Storage enclosures made of paper-based materials are commonly used to store and classify archival documents for their hygrothermal buffering effect. However, there is little information about papermaking and quantitative studies on such an effect. Aiming to assess the feasibility of using the enclosure to buffer temperature and relative humidity fluctuations, without any detrimental effect on the collections, this paper reports four measurements and a feasibility assessment: thermophysical properties of the enclosure material, hygroscopic properties of the material, air change rate of the enclosure, buffering effect in a climate chamber and the assessment of safeguarding collections without causing any detrimental effect. The measurement results show that the enclosure can buffer macro-environmental fluctuations, which was considered sufficient to mitigate temperature and humidity fluctuations from the room environment and to secure a condition inside that is safe for the collections. The paper-based material determines the buffering capacity of the enclosure, and an appropriate air change rate ensures average temperature and relative humidity inside the enclosure at a controllable level and prevents off-gassing accumulation. This work provides assurance that using enclosures is an effective approach to collection storage and establishes a significant basis for further heat–air–moisture simulation and energy-saving optimisation study in the service operation.