Humi temp and rh %

niterider56

ChestBeater
Found the following an interesting read on humi temp and rh%. This is a excerpt from the cigar advisor.

"You have stated that you personally do not agree with the much-heralded 70°/70% storage for cigars -- I believe the British tend to keep a slightly lower humidity level than some others, and it could also be a personal decision among individuals. In your opinion, what is your optimal storage environment? Thank you very much, and I rue the day that you can no longer provide the excellent advice and discussion which you have generously provided.

The short answer is, I do not know for certain.

Nevertheless I think I am still doing better than the people who know. People who repeated mumble the magical numbers 70/70 have not got a clue about when, where, how and why these numbers originated. Most of them do not even know how to calibrate their hygrometers (For electronic digital ones the error is typically +/- 2%, for analog ones, it may even be +/- 5 to 10%).

At least I tried to find out and have seemed to find something meaningful.

Curiously, nothing really scientific has ever been found on anything published. Mr. Alfred Dunhill had reported to have done some researches undertaken by England's National Physical Laboratory before the First World War. However I have no information about the results. Mr. Dunhill nonetheless, in his book 'The Gentle Art of Smokingâ€￾, recommended the ideal temperature for storage of cigars should be '60 to 65°F', but no specific figures for humidity was quoted.

This seems to concur with many recent experiments on the effect of heat on wines, which have concluded that the best temperature for storing wines is between 55 to 65°F, beyond 65°F, the fruitiness decreases irreversibly and the absolute cut off point is 70°F, where the rate of destruction of fruitiness increases exponentially. Fruitiness is believed to be aromatic esters which are quite heat unstable. Thus it seems wise to store cigars at 60°F to be on the safe side. A lower temperature would not hurt the wine (nor perhaps the cigar), but it would not serve any useful purpose as the maturation is delayed with no meaningful gain.

Further, the theory that tobacco beetle eggs will not hatch below 70°F has been proven (by me!) to be too optimistic. I had many first hand experiences that they hatch at 70°F, but I do not remember encountering a single occasion when there was a beetle problem when cigars are stored at 60°F.

Regarding humidity, nothing scientific is known about the exact figures but everyone who has any experience with vintage cigars share the unanimous opinion that the best humidity for aging cigars long term is between 60 to 65%. Cigars which are stored at 70% seem to fail to age as beautifully and it is well known that cigars which is too humid e.g. 75% will lose all their bouquets in no time.

I normally age my cigars at 60°F and 65% RH for new cigars. For very old cigars, I store them at 55°F and 60% RH wrapped air-tight. I do not know for certain whether these figures are the most 'correct', but it had worked so far so good.

So how did the 70/70 myth originated? A very good speculation goes like this :

Cigars taste best at 72% RH., minus 1% for each five years of age. I discovered this by trial and error ages ago. Sometime later I read from a book that Mr. Davidoff insisted to sell his cigars at 72%. He probably discovered this by trial and error too. As cigars sold a few decades ago had already been aged for a few years when leaving the factory, and reputable merchants like Dunhill insisted to age them further before release, a cigar which a customer bought in those good old days had typically been already 10 years old. They should taste best at 70% RH. And somebody had obviously made the easy mistake that if a cigar tastes best at 70 %, they should age best at the same RH. (Mr. Davidoff mentioned in his book 'The Connoisseur's Book of the Cigar' that the 'ideal' RH of storing cigars should be 'between 67 to 72%', apparently he had also succumbed to this method of thinking.

The 70°F probably originated when a certain 'expert' had decided that according to a nineteenth century book on insects that beetle eggs do not hatch below 70°F, cigars should therefore best be stored below that temperature. And naturally people would think that if cigars were best stored below that temperature, they should age best at that temperature as well.

As the 70/70 are round figures, they are easily remembered and most quoted. Eventually the most quoted becomes the truth, as the majority is always right. That reminds me of a saying by Mark Twain : 10% of people think, 10% of people think that they think, the remaining 80% would rather die than think."
 
Not only does Davidoff recommend the 68 - 72% figure, but also the giant manufacturer of cigars, Altadis. I seriously doubt that either succumbed to wive's tales when they published their numbers. The later goes as far as to say that a cigar stored at levels less than 72% does not age, but dries out. I have to say that my experience is that while certain cigars burn and draw better at lower Rh, the ones that I have had that have been stored at low Rh have tasted dry to me. But that is just it - it is all a matter of personal taste. That is why I tend to avoid the cigars that need to be dried out to perform and stick with cigars that will actual burn where I think they taste best - somewhere around 70%.

ps - on the lighter side; given the British reputation in the world of culinary arts, I am hesitant to trust anything that an Englishman or one from a former colony has to say about flavor. Perhaps they like having dried out cigars to go with the bland food :)

pss - note the smiley. Just a joke.
 
Call me a newb and stick me with a fork if you wish, but this is what I have learned so far.

Definition of Relative Humidity (RH): "Relative Humidity is the amount of moisture air can hold at different temperatures". Thus when talking about 70% RH what generally means is that this is an optimal humidity at 70 Degrees Fahrenheit (usually referred to as 70/70), suggesting that humidor humidity should be set according to the inner temperature of your humidor, and not by applying some magic number

Found a very useful Temperature and Relative Humidity Conversion Table table at Bonita Smoke Shop , that explains this in details: http://www.bonitasmokeshop.com/cigar_humidor_information_daniel.htm

According to the table this would imply, that if you are keeping your cigars for example in a fridge or cooledoor at 65 degrees Fahrenheit and an RH 65% then your cigars could be experiencing a long term humidity loss since the optimal RH for 65 degrees should be somehwere around 83%

Needless to say that there are some proponents that state that 70% is the optimal humidity without any regard for the temperature, and others swear for the 65% no matter what.

I am just posting this as general information, and so far I have used as guide for my 400 ct humidor with very good results, although I must say that I tend to use a higher RH than the recommended in the table. The average inner temperature of my humidor is 74F, and have managed to stabilize the RH at 64-66% (the chart recommends 61% RH).
 
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Found a very useful Temperature and Relative Humidity Conversion Table table at Bonita Smoke Shop , that explains this in details: http://www.bonitasmokeshop.com/cigar_humidor_information_daniel.htm

According to the table this would imply, that if you are keeping your cigars for example in a fridge or cooledoor at 65 degrees Fahrenheit and an RH 65% then your cigars could be experiencing a long term humidity loss since the optimal RH for 65 degrees should be somehwere around 83%

If you so a few searches, this has been discussed a number of times, and this table is complete, unadulterated crap.
 
I set the limit on my hyrdometer at 65% and never have thought twice about it since. Seems like a perfect balance of humidity and all the cigars smoke fine. In the early 90's everyone was storing their cigars too humid.

70-70 is just a catch tag phrase.
 
You will also find that not everybody believes that it is crap.

Sure, go ahead and store your smokes at 96% RH at 61F. Let me know how that turns out.

The table focuses on maintaining a the same partial vapor pressure of water, or specific humidity. This makes no sense whatsoever since it completely disregards the differing evaporation rates at different temperatures.
 
Ah... the plethora of opinions on this subject! Store 'em whichever way you think they smoke best. :ss
 
Through years of field research, (personal experience), I have found the following...

1. I have control over humidity in my humidor. I keep it at 65%

2. I have limited control over the temp in my humidor, but am able to keep it between 60 and 67 F.

This works well for me.
 
Through years of field research, (personal experience), I have found the following...

1. I have control over humidity in my humidor. I keep it at 65%

2. I have limited control over the temp in my humidor, but am able to keep it between 60 and 67 F.

This works well for me.

Bingo, although I use different numbers. With the common usage of beads, humidity is a lot easier to control. Temperature is not always as easy to control. I have found that a lot of the "humidity" fluctuations people complain about are really more a factor of temperature. Regardless of what some wish to believe, given a contant volume of water, RH will change with temperature. The temperature in my house will shift anywhere from 65 F and 75 F over the course of the year, and may shift as much as 5 F in a single day. Humidity reacts accordingly. I try to keep my humidors between 70 and 72% RH. If they go higher or lower, the first thing that I look at is the temperature. Beads don't react that quickly, and it often takes a couple of days for them to catch up to a temperature shift. So, if the temp drops and the RH goes to 75%, I usually don't panic unless it stays there. Same when the temperature goes up and the RH drops. I don't immediately add more water unless the RH stays down, or goes down with the temperature constant. Now, if I know that I am going to be at a certain temperature for a long time, and the RH is out of the band that I like to keep it for more than a couple of days, THEN I take some action to correct things. However, with a good humidor, the correct amount of beads, and minimal opening and closing of the humidor, I find that I don't need to add / remove moisture more than once every couple of months.

Personally, I think people make far too much of this subject and believe that Smokey Joe has the correct attitude on the subject.
 
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