Preservation

Comparison of Drying Methods

An archivist took daily measurements of  materials dried in situ and recorded data using a Delmhorst P-2000 moisture meter. The meter measures the relationship between moisture content and electrical resistance using a scale of 4.3-18% mc (moisture content). Five to seven percent (5-7%) moisture content is considered dry.  

Slide 24
Comparison of Drying Methods
Kaplan/Ludwig 2003

The in situ dehumidification drying trial ended on the 13th day of the project when the rented drying equipment was returned to the vendor.  Wet boxes did not dry during this time period. The least wet box diminished from 16.0 to 15.3% moisture content.  The temperature in the drying chamber fluctuated from 21–37° Celsius and the relative humidity was within 5-20% throughout the 13-day period. 

Slide 25
Comparison of Drying Methods
Kaplan/Ludwig 2003

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