My collection was infested with booklice and the instruction I got was to get a dehumidifier and lower the humidity to the 30% range, however the way my dehumidifier works it usually goes below that to 27% and then stops until it goes back to 33% then starts to work again to 27% and so on.
All of my books are stored in that room in boxes and so I cannot check their condition (it will be a huge hassle to open everything cause there are almost 100 boxes and I am moving in a few months so it is not practical to open them yet).
The dehumidifier was left at the 27% level for almost 2 years. I only recently discovered that low humidity can damage books and make them brittle/fall apart. I cannot find an exact RH figure in which this starts to occur though.
After my books have experienced relative humidity of 27% for 2 years, when I open the boxes will they all be damaged/brittle or is 27% not low enough to cause such damage?
Thank you so much in advance I am very anxious about this and would appreciate your educated answers/sources.
by mizdor