Stogie Tip: The Salt Calibration Test
Thursday, July 27th, 2006Over the past few months, I’ve provided you with tips on how to properly cut and light your cigars, I’ve discussed good cigar etiquette, and we even lent our advice on spotting counterfeits and golf. Now it’s time to learn how to harness that ever-elusive hygrometer.
Even the most amateur Stogie Guy knows that cigars need humidity for proper storage. Since they are hydroscopic in nature, stogies will – over time – dry out in an arid climate or absorb moisture in a humid one. Dry cigars yield high combustion temperatures, leaving the smoke hot and acrid on the palate. And wet cigars tend to fend off lighting, burn improperly, and split their wrappers.
What we need then, Goldilocks, is a happy medium between too dry and too damp. For the most enjoyable smoke, this equates to 12 to 14 percent of the cigar’s total weight in moisture (or about 60 to 70 percent relative humidity). If you have a humidor – which you should – your hygrometer measures relative humidity. That should make creating a cigar-friendly environment easy to monitor, right? Wrong.
Hygrometers, whether mechanical or electronic, can be grossly imprecise and may require adjustment or replacement. The simplest way to verify the accuracy of your hygrometer is to perform a simple salt calibration test.
Let me begin by mentioning that my BA in political science does not exactly qualify me to discuss the intricacies of chemistry. In fact, I have no clue why the salt calibration test works…it just does. You’ll have to take my word on that.
So here’s what you’ll need to perform this simple experiment:
(1) Distilled water (purchased from any grocery store)
(2) Coffee stirrer (or other thin, clean object with which to stir)
(3) Bottle cap (Snapple bottle caps work perfectly)
(4) Empty wide-mouth jar with lid (like an old mayonnaise jar)
(5) Tablespoon of plain table salt (I suggest Mortons – it’s made in Chicago)
(6) Your hygrometer (duh)
Place the tablespoon of salt within the bottle cap and slowly add distilled water to the salt while stirring with the coffee stirrer. Only add just enough water to moisten the salt so that it becomes a thick paste. Do not add enough water to dissolve the salt!
Place the bottle cap with salt gently into your wide-mouth jar and add your hygrometer. Make certain the sensor is exposed and is not blocked by the sides of the jar. Seal the jar so there are no leaks and put it in a place out of direct sunlight and with a stable, cool temperature (like your closet).
Leave the setup undisturbed for a minimum of eight hours. After that, check the reading on the hygrometer through the glass jar – it should read on or near 75 percent relative humidity.
Due to the salt paste reacting with the confined air, the ambient relative humidity within the jar will be exactly 75 percent. Most inexpensive hygrometers are only accurate to within 3 percent, so do not be surprised if yours reads 72 or 78 percent. Whatever it reads plus or minus our 75 percent benchmark is the amount of error of your hygrometer.
If your hygrometer has an adjustment potentiometer then, by all means, try to tweak it to exactly 75 percent relative humidity. You should repeat the salt calibration test after making any adjustments. If your hygrometer can’t be adjusted but the reading is close, then my advice is to not worry about it; just remember that your hygrometer is X percent off – either high or low. If the reading is grossly in error and you are unable to adjust it, you need to replace it.
Once you confirm your hygrometer’s accuracy and maintain a relative humidity of about 65 percent in your humidor, your cigars will age properly and be in peak condition when you’re ready to partake in their delicious flavors. Happy smoking!
I didn’t know about that…Thanks for sharing!
Does this work with Digital hygrometers too?
Sure does, Ray. As long as your device measures relative humidity, this test will work fine.
I believe the RH reading for the salt test is termperature dependent. If the temperature in the closet/jar is 75 degrees, for example, the salt test RH will be closer to 65. Or if the temperature is 65 degrees, it’ll be closer to 85. I may be mistaken, tho. Bring in the chemists!!
I am under the impression that’s incorrect. The relative humidity for the salt test calibration should be temperature independent. But I don’t know for sure. If anyone out there knows one way or another, please fill us in…
I just performed this test on my own hydrometer and, as far as I can tell, it worked perfectly. My gauge was reading about 4 percent too high, and now I have that adjusted. I recommend you give this a try.
[...] 3. Me and Steve finally took the initiative to check out my humidor. Check out Salt Test Calibration Test to see if your hydrometer is properly calibrated. [...]
Degrees Celsius versus RH of saturated salt solution:
0
75.51 ± 0.34
5
75.65 ± 0.27
10
75.67 ± 0.22
15
75.61 ± 0.18
20
75.47 ± 0.14
25
75.29 ± 0.12
30
75.09 ± 0.11
35
74.87 ± 0.12
40
74.68 ± 0.13
45
74.52 ± 0.16
50
74.43 ± 0.19
55
74.41 ± 0.24
60
74.50 ± 0.30
65
74.71 ± 0.37
70
75.06 ± 0.45
75
75.58 ± 0.55
80
76.29 ± 0.65
Regards.
[...] will tell you how accurate it is. There are lots of descriptions on how to do this, here is one Stogie Tip: The Salt Calibration Test or Calibrating Hygrometers Another thing that helps keep the humidity stable is a full humidor. [...]
[...] From time to time, Stogie Guys will specifically address new cigar smokers. And who knows, maybe a grizzled vet or two will stumble across something new as well. Here’s our first round of tips: Get a Little Salty: You need to make sure your hygrometer is properly calibrated to monitor the humidity level where your cigars are stored. There’s really only one way: the salt calibration test. Everything you need to know to perform this simple, effective operation is here. [...]
[...] little advice I’ve garnered conversing with some top collectors: 1) Be sure your humidor setup is accurate, and monitor it carefully. Many connoisseurs store cigars at temperatures in the 60°-65°F range [...]