If the humidity level is too low inside the humidor, then the following measures may be taken:
- It should be ensured that the hygrometer is calibrated according to the salt solution method, that the humidifier was filled with a propylene glycol solution (when using a sponge humidifier) and that the inside of the humidor was sufficiently moistened at first use.
- One may refill the humidifier with distilled water.
- If the decrease in humidity occurs after a long time of usage, it might be the case that the humidifier is defective. When using tap water for example the pores of the sponge can clog or with overly high propylene glycol levels the surface layer might prevent the further absorption of the distilled water.
The decrease in humidity immediately after putting dry cigars in the humidor is natural. After a few days, humidity in the humidor should stabilize. Also, opening the humidor leads to a short-term decrease in humidity within the humidor.
Deviations of a few percentages from the 70% mark should not be of major concern and one should also consider the explanations regarding the accuracy of humidity measurement (See hygrometer accuracy).