A humidor is any kind of box or room with constant humidity that is used to store cigars, cigarettes, or pipe tobacco. For private use, small wooden or acrylic glass humidor boxes for a few dozen cigars are used, while cigar shops may have walk-in humidors. Humidors can be used to store other goods for which a certain level of humidity is desirable; the Colorado Rockies Major League Baseball team stores game balls in a large humidor at their home stadium, Coors Field, to counteract the effects of Denver's high altitude and generally low humidity. Humidors of all sizes use hygrometers to keep track of the humidity levels.
Classification of humidors
Most common in cigar bars or stores. One room is built as or converted to a humidor where all the cigars are stored.
Usually placed on the floor as a piece of furniture. Typically holds 1000-5000 cigars.
Often quite heavy, though portable in theory, it is usually kept in one location. Capacity ranges from three hundred to a few thousand cigars. It usually comes with a polished wood exterior, marble, leather or combination of exotic elements, and glass top.
Semi-regular cigar smokers will sometimes keep a small humidor in their homes for personal storage, special events, or aesthetic characteristics of the humidor itself. Usually contains 20-75 cigars. This may also be known as a "Desktop Humidor".
Portable and made for carrying cigars enough for the outing or event, usually 2 to 10 cigars.
Commercially made humidor cases are typically made of wood, although other materials, like acrylic glass and metal, are not uncommon. Carbon fibre, silicon carbide, and polyethylene have also been used. Disregarding aesthetic qualities, the casing's purpose is to protect the interior and create a closed environment, so any durable and airtight material can be used.
Spanish-cedar is the most frequently used wood for the interior veneer of humidors. It possesses the following desirable characteristics for cigar storage:
- It holds more moisture than most woods, so it helps maintain humidity.
- It imparts its aroma to cigars if they are stored in it for long enough. For the same reason, some cigars are wrapped in Spanish-cedar sheets before they are sold.
- Spanish-cedar wood can repel tobacco beetles. These pinhead-sized beetles can ruin entire stocks of cigars. They eat the tobacco and lay eggs, causing further infestation. They can also be discouraged by ensuring the humidor does not get hotter than 20 °C (68 °F). The beetle eggs usually only hatch at around 25 °C (77 °F), although there are also instances where they will hatch at cooler temperatures if the humidity is too high.
- The wood properties are not prone to "warping" or "cupping" in high humidity.
In addition to commercially made humidors, homemade humidors are also in use. They range considerably in material, size and complexity.
Relevant for the capacity of the humidor are the interior dimensions of the humidor after deducting the space required for the humidification element and some extra space between the humidification element and the cigars. The exact capacity can then be calculated based on the diameter of the cigars that should be stored. For the most popular cigar formats, the capacity can also be calculated online.
The ideal humidity in a humidor is around 68-72% of relative humidity. Though it can go higher or lower depending on the cigar smoker's preferences, it should never go higher than 75% due to the possibility of hatching tobacco beetles. The more empty space, the more readily the humidity level of the box will drop or rise.
All humidors contain a humidifying system which keeps the air moist, which in turn keeps the cigars moist.
Most humidifying elements are passive, releasing stored humidity through evaporation and diffusion. The use of a 50/50 solution of propylene glycol and distilled water is recommended for replenishing the passive humidifying element as it has a buffer effect on air humidity, maintaining it at approximately 70%. Retailers and manufacturers claim it also has mild antifungal and antibacterial properties. In lack of propylene glycol, distilled water should be used, due to its lack of minerals, additives, or bacteria which keeps the contents neutral and healthy.
Electronic humidifiers are also available, although usually reserved for very large humidors. A sensor measures the outside humidity and then activates a ventilator, which blows air over a humid sponge or water tank into the humidor. Once the preset humidity level has been reached the ventilator stops [relative humidity]. This way electronic humidifiers can maintain a much more stable humidity level than passive humidifiers. Also they typically will activate an alarm to notify when the humidifier needs refilling, before the humidity actually drops. The accuracy of electronic humidifiers depends primarily on the integrated type of sensor. Capacitive sensors are the preferred type of sensors.
Usage of silica gel beads is a third alternative. These also have a buffer effect on relative humidity, and are moistened with distilled water when necessary. They can absorb or release humidity at RH 50%. Silica gel is commonly used to remove moisture from packaging containers. For use in humidors it is typically calibrated (by the additional coating of mineral salts) in various ranges of humidity including - 65%, 68%, 70%, and 72%. Unlike the passive devices, silica beads only require distilled water, and can be ruined by propylene glycol.
Each humidor has to be seasoned after being bought or having been out of use for a while. The seasoning process brings the wood inside the humidor close to the relative humidity level that it will be operating at so that the wood itself will buffer moisture. This can be done using different techniques including placing a small container of distilled water inside the humidor and allowing the wood to absorb the evaporated moisture for 1 to 3 days. Another technique involves wiping down the entire inside wood with a lightly soaked cloth, although this method is not recommended because the wood may warp. After the wood has been wiped a small container of distilled water is stored inside or a lightly soaked surgical sponge on top of plastic is stored in the humidor until the wood is sufficiently humidified to 65-72% RH. An unseasoned humidor will absorb humidity from the closed environment, which in turn will reduce the humidity of the cigars to the point of drying them out.
To discourage eggs of tobacco beetles from hatching, the humidor temperature should be kept below 25 °C (77 °F), as well as below 75% relative humidity. At lower temperatures below 12 °C (54 °F), the desired ageing process of the cigars is impaired. Therefore, cold wine cellars are only suitable for cigar storage to a limited extent. Similarly, temperatures over 24 °C (75 °F) can lead to worm infestation and cigar rotting. For this reason, the humidor should not be exposed to direct sunlight.