One of the easiest methods of verifying the accuracy of your hygrometer is to perform a Salt Calibration Test. Without boring you with the chemistry of why, let me simply state that this test will always result in an achieving an exact relative humidity level of 75%. The Salt Calibration Test Materials required: Tablespoon of plain table salt (NaCl) Wide Mouth Jar with Lid Bottle cap or other suitable small container (the wide-mouth ones that are used on individual serving juice or tea bottles are ideal) Swizzle stick (or other such item to stir with) Distilled water Your hygrometer Place the tablespoon of salt in the bottle cap. Slowly add distilled water to the salt while blending with the swizzle stick. You want to add just enough water to moisten the salt so that it begins to meld into a thick paste. Do not add enough water to dissolve the salt! Place the bottle cap with salt into the jar then add your hygrometer. Make certain that the sensor is exposed and not blocked. Seal the jar tightly as the test will not work if there are any leaks. Place the jar in a location that is free of direct sunlight and is a stable temperature. Leave undisturbed for a minimum of 8 hours. Check the reading on the hygrometer through the wall of the jar; it should read on or near 75% RH. Remember, most small, inexpensive hygrometers are only accurate to within 3%; do not be surprised if it reads 72% or 78% RH. It is exactly 75% RH within the confines of the jar due to the salt paste reacting with the air, and what your hygrometer reads differently is the amount of error. What to do about an off reading depends on the circumstances. If your hygrometer has an adjustment potentiometer, then by all means try to tweak it to exactly 75%. You should repeat the Salt Calibration Test after making any adjustments. If your hygrometer can't be adjusted and the reading is close, then don't worry about it - just remember that your hygrometer is X% off, either high or low. If the reading is grossly in error and you are unable to adjust it, then I suggest you replace the hygrometer. And finally, let me say that hygrometers are not really necessary. You will find, over time, that you are able to judge the relative humidity within your humidor by simply touching and smoking your cigars. return to Cuban Cigars home page |
http://cubanmadecigars.com/ind.html |
