Author Topic: Managing humidity with salt solution  (Read 1097 times)

Offline scasnerkay

  • Old Cheese
  • *****
  • Location: Sunnyvale, California
  • Posts: 721
  • Cheeses: 157
  • Default personal text
Managing humidity with salt solution
« on: January 04, 2014, 01:00:07 PM »
I came across this idea on NEC blog today and thought that if others had not seen it, they might find it interesting....

""Making a saturated salt solution in a ratio of 1 tablespoon of table salt and approximately one teaspoon of water, and mixing until a "slushy snow" consistency; yields a stable humidity controller when used in conjunction with an equal amount of water.  One acts as a humidity source while one acts to regulate the humidity.  The salt solution takes an initial 12 hours to stabilize.  This solution, alone, in a closed sandwich bag along with a hygrometer may be used in calibrating the hygrometer. The solution will yield a stable 75% RH in such a small environment.""

Offline John@PC

  • Old Cheese
  • *****
  • Location: Hartsville, SC
  • Posts: 987
  • Cheeses: 92
  • Default personal text
    • Perfect Cheese
Re: Managing humidity with salt solution
« Reply #1 on: January 08, 2014, 05:39:39 PM »
Thank you for this reminder.  Most of the humidity sensors we like to use (like the Acurite 614) has an accuracy of only +/- 5% RH and the sensors can be subject to long term drift due to the conditions in the cave.  Checking with the saturated salt solution is very easy to do, and if you find your sensor is slightly off the mark it's probably drifted a bit and instead of tossing it you can just do a mental "adjustment".  Also,  if your sensor is reading way off the mark you may want to set it outside the cave in a dryer environment to see if it corrects.