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有關圖書館的溫濕度,答復如下:
壹、
問  題: 請問國家圖書館書庫的溫度、濕度的設定為何? 
解  答: 
普通書庫:溫度22度,濕度50% - 60%
善本書庫:溫度20度,濕度50% - 60%
資料來源:
 國家圖書館 參考服務 問題選粹 
貳、
四、書庫安全
(三)溫濕度合宜
1.書庫內溫度經常維持在25℃,相對濕度50%為宜。溫濕度的調控可借助空調除濕設備。
資料來源:
 高級中學圖書館工作手冊, 第十一章,典藏與維護 
叁、
humidity 
……Relative humidity (RH) is the ratio of the amount of water vapor present in a given volume of air to the amount required to reach saturation (condensation into droplets) at the same temperature, expressed as a percentage. Relative humidity varies with temperature and air pressure--warm air can hold more water vapor than cooler air. It is the most important factor in providing a suitable environment for books and other items made of paper, with 40 to 45 percent RH considered ideal for permanent storage of library and archival materials. Mold can become a serious problem when RH exceeds 70 percent.
資料來源:
 ODLIS — Online Dictionary for Library and Information Science 
肆、
temperature 
……Conservators consider 60-70 degrees Fahrenheit best for storing books and other printed materials……
資料來源:
 ODLIS — Online Dictionary for Library and Information Science