I use a goldenrod (https://www.amazon.com/Goldenrod-725721-GoldenRod-Original-Dehumidifier/dp/B00D1WYXR0/ref=sr_1_5?ie=UTF8&qid=1506948585&sr=8-5&keywords=gun+safe+rod) & large DampRid in my gun safe. I REALLY want to put my books in the safe, but am not convinced it's a good environment. I keep a digital hygrometer that, aside from real-time temp/humidity, records min/max values. I just checked and min/max temps over the past month were 65/83 degrees, and relative humidity readings were 45/52. I think the humidity is ok, but the temp swing is too wide for books, right? Probably from the goldenrod, which generates heat...
What do y'all think? Okay for my books? Or no bueno...?