I have a Ft Knox with a door switch hooked into some fluorescents so they come on when the door opens. I also have a Goldenrod that is on all the time. I did have a problem this summer even with the goldenrod on, the room got some water in it and I think that some must have wicked up into the carpeting of the safe. It never rusted anything but I did get some mold on the gunstocks. It was an intermittent problem all this fall, and I only was confident this winter that I've gotten all the moisture out. I would leave the door open after I put all the kids down, then close it in the morning before they got up (hopefully they know enough to get me before they play with anything in there anyway but that's a different story). I had to do that for a week before I was comfortable that it was dry enough. Having a fan didn't seem to speed it up that much, curiously enough.

Thanks for the heads up on the lights!!!
As far as drying out the inside of your gun safe I have a couple of things that have saved my guns from harm.
Go to your local motorcycle shop or snowmobile shop and get a couple of the large bags of dessicant that they just throw away. They are in with every bike or sled that is shipped. You might even find them in the dumpster. I have 2 of these about 8 inches square that I leave on the racks or shelves in my safe and the have kept it very dry.It's easy to get new bags if the old ones soak up to much moisture.
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