I have never seen any information on the value of adding humidity to distribution center environments. Food marketers almost never release data on their losses so it is unlikely that this information is available to anyone except in-house personnel. Humidity recommendations for distribution centers are a compromise between the value of high humidity in reducing wilting and shriveling of products and the damage caused by high humidity weakening corrugated boxes. Weak boxes allow products to be bruised and cut in handling and transport. We recommend highest humidities (90% - 98%) only for rooms that hold leafy vegetables. These products are most sensitive to moisture loss and some are packed in waxed boxes that resist moisture damage. For other products, acceptable relative humidity is in the range of 85% - 95%. In some situations a better way to reduce shriveling is to wrap the product in plastic film or pack it in clamshells containers or plastic box liners.

-Jim Thompson