View Full Version : Effectiveness of Dessicant

04-03-2011, 7:12 PM
What has your experience been with dessicant in your safes? I have been trying unsuccessfully to get the humidity down in my safe. It has a golden rod and I have since added three 750g dessicant cans and still have never gotten the humidity inside the safe down below the low 40's (about 42% at best, and that was short lived). Ambient humidity is normally around 55% and I think it should be able to get the humidity much lower, but I have never been able to. Lately I have even been recharging the dessicant weekly, even though the indicators do not show that they are saturated.

It's not like I have an open bottle of water inside the safe. I've always kept all of the firearms inside silicon sacks as a safety measure. I am just not sure why I cannot get the humidity lower.

Any advice would be appreciated.


04-03-2011, 10:24 PM
Mine is pretty successful. I actually had to refresh it under 6 months. Odd that when rainy season started last year, I suddenly saw little rust spots on the container where as I didn't like in November/December and early January. it's like a sudden outburst of moisture.

Called the dessicant company and they said it gets saturated pretty fast in the beginning. Some kind of break-in period maybe? But I've not had to renew it after 1 more after that. Company said takes about 2-3 times in either monthly or bi-monthly before it goes on "normal" saturation unless you really have high humidity.

Now I'm OK. I just check the crystals 4-6 weeks since I've not been heading out much.

How were you able to tell you can't get the humidity controlled/lower if the indicators are not saturated?

04-04-2011, 9:31 AM
Thanks for the reply.

I put a digital hygrometer in the safe, along with the color inidicating paper humidity gauge that came with the dessicant canisters. They seem to match each other pretty well. (when they first went in, both indicated over 50% RH, despite the golden rod and the one dessicant pack...I have since added 4 more, but with little effect as read by the gauges).

At first, I had high hopes as when I really bombarded the safe with dessicant, the levels started to come down. A week later I recharged the packs and put them back. Yesterday (yet another week later) when I checked again, the humidity level had actually increased about 4%....not at all what I had expected. It just doesn't seem like despite the safe being a closed space that they are doing much to bring humidity levels down much below ambient conditions.

As far as longevity, I actually find that the older packs seem to saturate more quickly (the color indicator changes within a few weeks). The newer packs seem to last longer before indicating a recharge is necessary.

I don't have any rust problems, but I was expecting to be able to get humidity levels down at least into the 30's or maybe even 20's.

04-04-2011, 10:30 AM
I remember reading that at the NRA museum they keep their collection at a constant 70 degrees and 50% humidity. Wood stocks can shrink at too low of humidity.
45%-55% range is fine. I've never seen any rust on any of my guns. Just keep them clean and oiled once in a while and keep using the golden rod/dessicant combo and you should be ok. Also most common cheap humidity gauges are not very accurate but they get you in the ballpark.

04-04-2011, 8:02 PM
If that's true, there is no real reason to run the dessicant packs as that is about normal humidity around here. I know the gauges may not be the most accurate, but like I said, the packs came with a color indicating humidity gauge that is reading about the same as the digital gauge, so I figure it is pretty close.

04-05-2011, 10:33 AM
I've tried the golden rod and the dessicant route and one of the more effective humidity removers I've found is a small 30W bulb. The bulbs are rated to last ~3.4 months but my latest bulb has been operating nearly 20% longer than its rated life.
If you want to cut down on the lamps operating time, a simple timer is <$10.

Total cost for my setup (electricity for goldenrod + electricity for lamp running 24/7 + amortized cost of the bulb) = $3.72/mo


04-05-2011, 12:17 PM
My experience with dessicant is from using it in antennas when I was int he navy, so it may not apply.

We used desiccant not as a humidity control tool, but to absorb excess moisture that may get into the systems. Sometimes I could go 6 months or more without the color changing, sometime it had to be baked every couple of weeks. It really depended on where we were in the world and the weather at the time.

I would take the fact that the desiccants aren't indicating they need to be baked as a good sign that all is well.

04-07-2011, 8:22 AM
Maybe my expectations are just too high. I was expecting between the golden rod and the dessicant that the humidity level would decrease, not just stay at ambient levels.....