This study was conducted to investigate alternatives to the relative humidity buffers used in an enclosed space, such as silica gels and Nikkapellet. Various agricultural products, and also some industrial products were tested for their equilibrium moisture content, their specific moisture reservoir, and their response time to the change of relative humidity in the environment. Some of these materials were applied to experimental showcases, and the specific moisture reservoir was deduced. The result of a series of experiments showed that the agricultural products may be applied to showcases as a relative humidity buffer, but that the specific moisture reservoir should be studied with the relationship between the air leakage rate of the showcase, and the response time of the buffering material. -- AATA