After a long period of experience accumulation, cultural relics workers have a definition of the optimal temperature and humidity for cultural relics maintenance. Generally speaking, the best temperature for antique collection should be 14℃-20℃, and the 24-hour temperature difference should not exceed 2℃-5℃; The humidity should be 50%-65%, and the change of relative humidity should not exceed 3%-5%. The basis of this standard is that in this range, the destruction speed of various chemical reactions and unfavorable factors is not very fast. If the temperature standard is set lower, such as 8℃- 10℃, it should be more conducive to the durability of antique materials, but considering other factors in maintenance, the temperature standard should not be set too strictly.
As for the humidity, most of the ancient books, calligraphy and painting, archives and other paper cultural relics have the best strength when the water content of paper is around 7%, so the water content of 7% is called the normal water content of paper. During storage, in order to keep the water content of these cultural relics around 7%, it is required to control the humidity of the surrounding environment between 50% and 65%. Such a humidity standard can maintain the normal water content of paper, thus ensuring the durability of such cultural relics.