Desiccant bags and silica gel prevent condensation by absorbing and holding moisture. Desiccants also regulate the ambient humidity and prevents it from rising above a critical level. In order to reach an optimal low Rh, desiccant bags must be included in moisture barrier bags. Dri Bag desiccants are made up of a mixture of calcium chloride, clay, and breathable yet strong fabric. Desiccant bags must conform to IEC 61340-51 standards.