I use one of these:
http://www.eva-dry.com/products/eva-dry ... humidifer/
Fight dampness in boats, safes, RVs and BIG closets
The E-500 fights and protects against dampness in boats, RVs, large safes and larger closets. This eco-friendly dehumidifier silently and reliably protects against mold, mildew and moisture in areas larger than the Eva-Dry E-333, units and lasts 30-60 days before renewing. Special features of the E-500 includes: the unit works in areas up to 500 cubic feet, requires no batteries or cords for use, is 100% renewable, works up to ten years, is compact/silent, always spill and mess free and is non-toxic, child and pet safe! The unit measures 8" L , 2 ½" W, 5 ½" H.
Plug in to renew! (12-15 hours)
The crystals change color from blue to pink as they absorb moisture. 2 or 3 times a year, I take it out of the safe, plug it into a wall socket or extension cord, and a few hours later the crystals are back to a dark blue. It never takes the full 12-15 hours it says above. I've had the thing in my safe now for about 5 years and it keeps on truckin'. Best $30 I ever spent.
If you plug it into an extension cord and lay it on its side while its "cooking" out the humidity, you'll see a lot of moisture accumulate on the surface it is laying on. It's surprising how much it absorbs. I don't remember for sure where I bought it, but I
think got somewhere like Cabelas or Bass Pro.
“Hard times create strong men. Strong men create good times. Good times create weak men. And, weak men create hard times.”
― G. Michael Hopf, "Those Who Remain"
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