Hygrometer Calibration of a Cigar Humidor

Analogue Standard Hygrometers

Digital Hygrometers

Determine reference values

There are several ways to determine the desired ideal value for a hygrometer. In recent years, the belief has become common in some places that exact 70% rel. Humidity must prevail in a humidor. Everything else was dangerous. There are two theses:

1.) Exact 70% is a possible stock value. In fact, long-term storage tends to occur at around 60%, while cigars for consumption are readily stored by many smokers at e.g. 75%. Personally, I have for the purpose of a small humidor with about 75% humidity in operation with an amount of humidifier capacity above the normal recommended range.

2.) For a review, the measuring devices already do not exist or are priceless for the private user resp. not available. However, none of the commercially available hygrometers are able to measure 70% accurately. Achieved ideal values ​​thus give a good picture, but are not based on valid measurements such as would be necessary in medicine. I therefore recommend only aiming for a value "against" 70%. Such thinking saved the user time, nerves and costs.
Cigars do not need an exact 70%.

Unfortunately, the assumption is still carried out by the industry into the world. At fairs, we often meet people smile in conversation about such theses. Due to the topic, all parties are partly put under unnecessary pressure.
I can only advise prudence in the issue of measuring moisture. Who likes to invest in a dew point mirror and medical hygrometer, of course, can do that. These are great devices. The costs are in the more or less elevated four-digit area. The effort drives no cigar lounge known to me, because it's unnecassary. On the other hand, they definitely use the same devices that we manufacture or sell.

There's only demand for a reliable value. There are x methods for that. What they all have in common is that an action in a confined space achieves an inherently reliable level of humidity. We present two popular methods below.

1.) Wet Cloth method

Just wrap the hygrometer in a damp cloth for about 1 hour. It should then stand at about 98%. The needle should be just below 100%, so as not to leave the measuring range.
Advantage: Very simple in implementation, therefore practical.
Disadvantage: Each hygrometer has a precision area in which it measures very precisely. An adjustment above limits thus contains understandable disadvantages.

2.) The steam method

There are many different variations with different considerations. Often, water is boiled and steam is used as a reference point. I advise against it, because too much mistakes are made. No hygrometer wants to be boiled in water. :)

The method takes advantage of the fact that a saline solution provides physically predictable and stable values. In the example, take a vessel (pot). This is filled to at least about 10% of its volume with a saline solution. On 100ml of water come 40g of sodium chloride. So you mix in a 40% saline solution. When the salt is dissolved, place the hygrometer inside on a pedestal, such as an inverted glass. Thereafter, the vessel is closed airtight. At 20 ° C ambient temperature to get the desired value of just over 70%. After 2-4 hours of waiting, you can set the hygrometer to about 74%.

A variation of the pot variant is the following: A small glass (shot glass, Stamperl) is filled with 2 tablespoons of salt and a few drops of water. It results in a salt mixture. This is hermetically sealed together with the hygrometer in a bag. After 2-4h the 74% can be adjusted in the same way.

How to open the hygrometer? We have a collection of opening procedures on some gauges. Please refer to our hygrometer opening site.