For those of you who aren't aware, relative humidity (RH) has a particular gotcha. As the temperature increases, the amount of humidity the air can hold also increases - this has been covered in many posts. The most obvious example of this is the case of a room in which the temperature moves up several degrees during the day and goes back down in the evening/night. As the temp increases, you may notice your RH reading goes down. This might lead one to believe that their humidor is under humidified - not necessarily so. In all likelihood the amount of moisture in the humidor hasn't changed, only the temperature has.
For example, if you calibrated your humidor to 70% RH while the ambient air was 70 degrees, the relative humidity (RH) at 75 degrees would be approximately 60% - without any changes to the actual moisture in the air whatsoever!! Now, if you then went and added more humidification to compensate, you'd be over-humidifying your stash immensely.
So what's the point? There is none. I just wanted to share the quick reference I use to help me keep my sanity with my many smaller humidors. I had a prof friend from UofT help me calculate all the compensated values for humidity at various temperatures. The chart below provides RH values for 65, 68, 70, 72, and 75 (salt test). The range assumes you calibrated at 70 degrees, and therefore deviances are provided with that in mind. So in simple terms, if you want to maintain 65% humidity for your sticks, refer to the 65% column. If your meter reads 55% and the rooms is a toasty 75 degrees, don't freak out and add more moisture to your cab - it’s all good! This is meant to be a 'good' guideline, but not perfect. There are some assumed values in this calculation, but for all intents and purposes they work for pretty much everyone.
For example, if you calibrated your humidor to 70% RH while the ambient air was 70 degrees, the relative humidity (RH) at 75 degrees would be approximately 60% - without any changes to the actual moisture in the air whatsoever!! Now, if you then went and added more humidification to compensate, you'd be over-humidifying your stash immensely.
So what's the point? There is none. I just wanted to share the quick reference I use to help me keep my sanity with my many smaller humidors. I had a prof friend from UofT help me calculate all the compensated values for humidity at various temperatures. The chart below provides RH values for 65, 68, 70, 72, and 75 (salt test). The range assumes you calibrated at 70 degrees, and therefore deviances are provided with that in mind. So in simple terms, if you want to maintain 65% humidity for your sticks, refer to the 65% column. If your meter reads 55% and the rooms is a toasty 75 degrees, don't freak out and add more moisture to your cab - it’s all good! This is meant to be a 'good' guideline, but not perfect. There are some assumed values in this calculation, but for all intents and purposes they work for pretty much everyone.
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