How to Calibrate your Hygrometer
It is a beautiful Friday night. You decide this is the perfect time to sit out on the back porch, drink a glass of your favorite Scotch, and enjoy one or maybe two of your premium cigars that you have had resting in new humidor you got last month. You walk over, crack open your humidor, pick up a stick and damn it… your cigars are completely dried out. You instantly look at your hygrometer and it reads a perfect 70%! What the hell is going on?! Then you realize you have never calibrated your hygrometer and don’t even know how. Well you are in luck, because I am about to explain how to do just that, using a very easy technique called the ‘salt test’.
What you are going to need:
Water bottle cap
First thing, grab up your salt and the bottle cap that you are going to be using. Next, you are going to want to fill the bottle cap about ¾ of the way full.
Now slowly drip water into the cap of salt. I usually use my finger for this by dipping my finger in the water and letting the droplets fall off the tip of my finger and into the salt.
What you are looking to create is a slush like consistency, you don’t want to have any standing water on top of the salt. If for some reason you do accidentally put too much water, just use a paper towel to soak up excess water, until you reach the desired consistency.
At this point you are going to grab your Tupperware bowl, remove the lid and place the prepared salted bottle cap inside along with the hygrometer that requires calibration.
Once you have both your hygrometer and your salt inside your Tupperware, place the lid on and place the Tupperware in the same place as your humidor. Some may say it doesn’t matter where you put the Tupperware, but I like to place it with the humidor so that your hygrometer will be calibrated in the same environment as your humidor.
Now what exactly is going on inside your Tupperware and how does it help you calibrate your hygrometer? Well, when you do this test, the paste in the cap reacts with the air to create an environment that is exactly 75% relative humidity. So what does that mean to you? Well once you waited the 8 hours, your hygrometer should read 75%.
If they don’t, then you will know exactly how far off the calibration truly is! Now you can make the necessary adjustments to your hygrometer (read your instruction manual) to ensure that your humidor is reaching and staying at your desired levels.
Hope this was helpful, and Good Luck!