Puff Cigar Discussion Forums

DonnieW · 07-10-2008, 09:36 PM

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.

chip · 07-10-2008, 09:48 PM

This has been beat to death so many times, but I guess every now and again it is good to revisit it.

Total

You want to measure RH, not AH....and this chart (and others like it) over think the issue. Have you ever heard a weatherman qualify his RH with temperature?

Find the RH you like....and keep it there. Temperature swings are to be avoided as much as possible, but bottom line is they don't matter so much.
I have kept cigars in humidors at 78 degrees F (in Texas) with no problems. I have had exactly one cigar hatch 3 beetles, it was a custom rolled that was recently bought at a local shop. I never freeze my cigars, either. Too much work for too little return, I am not convinced home freezers are cold enough to actually kill the beetle eggs.
The dreaded beetles usually require high temp and humidity, so following your chart and trying to keep the same (false) RH (which at least you did not suggest) is a recipe for disaster.

O-Danger · 07-10-2008, 09:55 PM

Quote:

Originally Posted by chip

This has been beat to death so many times, but I guess every now and again it is good to revisit it.

Total

You want to measure RH, not AH....and this chart (and others like it) over think the issue. Have you ever heard a weatherman qualify his RH with temperature?

Find the RH you like....and keep it there. Temperature swings are to be avoided as much as possible, but bottom line is they don't matter so much.
I have kept cigars in humidors at 78 degrees F (in Texas) with no problems. I have had exactly one cigar hatch 3 beetles, it was a custom rolled that was recently bought at a local shop. I never freeze my cigars, either. Too much work for too little return, I am not convinced home freezers are cold enough to actually kill the beetle eggs.
The dreaded beetles usually require high temp and humidity, so following your chart and trying to keep the same (false) RH (which at least you did not suggest) is a recipe for disaster.

I understand the science behind this and still humidity charts are a no go. RH is king. That being said don't stress it. anywhere from 63%-73% and my smokes are doing fine

.

DonnieW · 07-10-2008, 09:55 PM

Quote:

Originally Posted by chip

This has been beat to death so many times, but I guess every now and again it is good to revisit it.

Total

You want to measure RH, not AH....and this chart (and others like it) over think the issue. Have you ever heard a weatherman qualify his RH with temperature?

Find the RH you like....and keep it there. Temperature swings are to be avoided as much as possible, but bottom line is they don't matter so much.
I have kept cigars in humidors at 78 degrees F (in Texas) with no problems. I have had exactly one cigar hatch 3 beetles, it was a custom rolled that was recently bought at a local shop. I never freeze my cigars, either. Too much work for too little return, I am not convinced home freezers are cold enough to actually kill the beetle eggs.
The dreaded beetles usually require high temp and humidity, so following your chart is a recipe for disaster.

Its got nothing to do with beetles, etc. that wasn't the spirit of the post at all. Simply converting the numbers for an easy time keeping smokes from being to soggy. I'm at 80 degress in my office, thus setting my humidty to 70% would make my sticks look like wet noodles. I simply calculated the correct value to compensate. I didn't find any charts here so I put it up. Nonetheless thanks for humoring yet another thread

NCRadioMan · 07-10-2008, 09:58 PM

Quote:

Originally Posted by DonnieW

I didn't find any charts here so I put it up.

Because they have been de-bunked. 70% rh is 70% rh no matter the temp.

DonnieW · 07-10-2008, 09:59 PM

Quote:

Originally Posted by O-Danger

...anywhere from 63%-73% and my smokes are doing fine

.

I rest my case!

chip · 07-10-2008, 10:00 PM

Quote:

Originally Posted by DonnieW

Its got nothing to do with beetles, etc. that wasn't the spirit of the post at all. Simply converting the numbers for an easy time keeping smokes from being to soggy. I'm at 80 degress in my office, thus setting my humidty to 70% would make my sticks look like wet noodles. I simply calculated the correct value to compensate. I didn't find any charts here so I put it up.

Untrue....what the chart calculates is the RH needed at a specific temperature to keep the same AH (absolute humidity).
AH is not something to concern yourself with.
70% RH is too high in my opinion, anyway. Others here find it just perfect, it's all up to your preference. Temperature has nothing to do with it.

And I understand the spirit of wanting to share knowledge, I am not trying to be a wanker....although it would not be the first time I appear to be...

DonnieW · 07-10-2008, 10:03 PM

Quote:

Originally Posted by NCRadioMan

70% rh is 70% rh no matter the temp.

That's absolutely correct. But the actual water in the air is completely different.

chip · 07-10-2008, 10:06 PM

Quote:

Originally Posted by DonnieW

That's absolutely correct. But the actual water in the air is completely different.

And so is the evaporation and absorption rates of medium. Which is why cigars do well at a fixed RH.

DonnieW · 07-10-2008, 10:10 PM

Quote:

Originally Posted by chip

Untrue....what the chart calculates is the RH needed at a specific temperature to keep the same AH (absolute humidity).
AH is not something to concern yourself with.
70% RH is too high in my opinion, anyway. Others here find it just perfect, it's all up to your preference. Temperature has nothing to do with it.

And I understand the spirit of wanting to share knowledge, I am not trying to be a wanker....although it would not be the first time I appear to be...

I haven't come across any wankers here, frankly that's what I like about this place.

Preferences are just that, I completely agree. But temp does play a big part - screw beetles, it’s simply the effect on humidity. If temp had no effect on things, you'd be taking it in the a$$ at the gas pump even more than we are now - i.e. volume correction. I can explain molecular composition of warm air versus cooler air if anyone wants to know, and how it affects humidity. But I don't want to digress.
[SIZE=3] [/SIZE]
Like O-Danger said, between such a wide spread his smokes are just fine... That's ALL I wanted to re-enforce with this post. Seems like I've read a million threads with people freaking about swings in their RH readings and spending needless time worrying about it.

NCRadioMan · 07-10-2008, 10:13 PM

Here are few threads about the infamous chart:

http://www.clubstogie.com/vb/showthr...humidity+chart
http://www.clubstogie.com/vb/showthr...humidity+chart
http://www.clubstogie.com/vb/showthr...humidity+chart
http://www.clubstogie.com/vb/showthr...humidity+chart

Also, here a good read on water vapor myths in case anyone is interested. Thanks for the link, poker! http://www.meto.umd.edu/~stevenb/vapor/

DonnieW · 07-10-2008, 10:15 PM

Man... I'm gonna take it in the ass on this one aren't I

NCRadioMan · 07-10-2008, 10:16 PM

Quote:

Originally Posted by DonnieW

Man... I'm gonna take it in the ass on this one aren't I

Nah! I think alot of folks will learn alot from this thread and that is what it's all about.

chip · 07-10-2008, 10:20 PM

Quote:

Originally Posted by DonnieW

I haven't come across any wankers here, frankly that's what I like about this place.

Preferences are just that, I completely agree. But temp does play a big part - screw beetles, it’s simply the effect on humidity. If temp had no effect on things, you'd be taking it in the a$$ at the gas pump even more than we are now - i.e. volume correction. I can explain molecular composition of warm air versus cooler air if anyone wants to know, and how it affects humidity. But I don't want to digress.
[SIZE=3] [/SIZE]
Like O-Danger said, between such a wide spread his smokes are just fine... That's ALL I wanted to re-enforce with this post. Seems like I've read a million threads with people freaking about swings in their RH readings and spending needless time worrying about it.

I am an engineer (some here have a greater knowledge of chemistry, but some "experts" spout pure bunk), and although everything you have said is correct, MY POINT is you have not considered everything. There is that whole pesky air/medium interface to consider.
And you are right about gas, I believe pumps are calibrated at 72 degrees or so, and since they measure gallons indirectly by volume, we get less than a gallon if the temperature is higher than the calibration temperature.

I can't believe I have posted this much on a single thread, or even a single evening....

Lively conversation....enjoy a good smoke, my friend!!