The Aging of Archival Storage Boxes as Indicated by pH.

In order to determine if the pH of archival storage boxes decreases over time, experimental research was performed by sampling 25 Hollinger, one cubic foot, archival storage boxes from the Kent State University (Ohio) Archives. Boxes chosen for testing were new, 5, 10, 15, and 20 years old. Each box was tested for pH value using pH pens and a cold extraction method, both in duplicate, to see if there was a relationship between pH value and age of archival box. Most of the 10 to 20-year-old boxes increased in acidity in comparison to their original pH values. A few of the 10 to 20-year-old boxes were still acid-free. All new and 5-year-old boxes were found to be acid-free. The average cold extraction pH value is 9.4 for new boxes, 9.0 for 5-year-old boxes, 6.5 for 10-year-old boxes, 6.9 for 15-year-old boxes, and 6.5 for 20-year-old boxes. A correlation was done using the cold extraction pH results from the 10 to 20-year-old boxes, which produced an r-value of -0.436, showing a negative correlation between time (age of storage box) and pH value. Data are presented in table form. Contains 15 endnotes and 10 references. (Author/DLS)