Myth Busters – Relative Humidity

[Mitch]

RH is the amount of water vapor present in relation to how much the air could hold at it’s given temperature, but because the amount of water vapor the air can hold changes with temperature (it holds more the warmer it gets) a steady RH over a temperature range represents a rather drastic difference in the amount of water vapor present.

The debate comes from the question, what if you get away from the 70 degree range. Is 70% still the correct RH % to aim for? On one side, there is a belief that the proper range of humidification is a fixed amount of water vapor and since relative humidity (RH) is a function of temperature, the ideal RH must change when the temperature changes. If you use math and formulas for air it looks something like this.

RH% Temp
50.17 @ 80
53.58 @ 78
57.25 @ 76
61.20 @ 74
65.47 @ 72
70.07 @ 70
75.05 @ 68
80.42 @ 66
86.23 @ 64
92.60 @ 62
99.30 @ 60

Some have even gone as far as saying that charts like this should be used to determine what RH you should aim for.

The other side believes that the RH of 70-73% is always good regardless of the temperature.

The best test I have ever found for if a cigar is well humidified is to hold it, see how firm it feels in the hand and see how tight the band is on the cigar. If the band is snug, but loose enough to spin, it’s about right in my opinion. So, my experience tells me is that what matters is the state of swell of the cigar.

The experiment…

Since both camps seem to agree that a 70% RH is a good number I’m going to try to get close to that.

The hygrometer was calibrated about three weeks ago with a Bovida kit.

I have taken four pairs of cigars from my cabinet humidor that has been under fairly constant 69/69 conditions and placed half of them with the calibrated hygrometer from that humidor into an air tight plastic container. All of these cigars have been in the humidor for at least three months. I note how tight the bands are on the cigars (to detect swelling or shrinking of tobacco) and then weigh the cigars with the most accurate scale I can find to track if water is added or taken from the total weight of the cigars.

Day…Temp…RH%..... Cigar1…Cigar2…Cigar3…Cigar4……….Net Weight

Start...69…….69………Snug…..Snug…...Spins….Unbanded…..32.4g

Then I placed the plastic container on top of my TV’s Cable Box/DVR that stays on all the time to raise the temperature to over 90 degrees. I know I have a chance of hatching beetles at this temperature, but if that happens they will be in a sealed thick plastic container far away from where my other cigars are kept. At this point the only thing in the container is the four cigars and the hygrometer. I know that if the only thing in the container was air, as it gets warmer the RH % should drop. But there are also cigars in there, and they contain moisture that they could release, or they may try to soak up more moisture from the air, or they may just stay stabilized with the air. So, this is my first area where I am not sure of what to expect. My guess is that since the container is air tight and water vapor can not get in or out, the cigars will not change in weight at all. If that is the case, I’d expect RH % to drop simply because it is a measurement relative to temperature.

Day…Temp…RH%..... Cigar1…Cigar2…Cigar3……..…Cigar4……….Net Weight
1…….93…….59………Loose....Loose…..Very Loose….Unbanded…..32.1g

Day 1-All of the cigars feel good to the touch. Bands are notably less snug on the cigars so the cigars shrank a bit, also lost .3g of weight. So, in a completely sealed environment with no humidification device the cigars dried out a bit. If you look at the RH chart however, the RH was not nearly as low as it should be, so it seems the lost moisture from the cigars is in the air.

Then place some 70% beads into the container and seal it up for a week and check on it each day. First I am curious of how the beads work and want to establish if they always produce 70% RH regardless of the . Second, is that I want to see what happens to the cigars over the week as far as weight and swelling.

Day…Temp…RH%..... Cigar1…Cigar2…Cigar3……..…Cigar4……….Net Weight
2…….94…….68………Snug…..Snug…...Spins………...Unbanded…..33.3g
3…….94…….68………Loose....Snug…...Loose………...Unbanded…..32.5g
4…….94…….68………Loose....Loose…..Loose………..Unbanded…..32.4g
5…….95…….68………Loose....Snug..…..Loose………..Unbanded…..32.4g
6…….94…….66………Loose....Snug..…..Loose………..Unbanded…..32.4g
7…….94…….68………Loose....Snug..…..Loose………..Unbanded…..32.2g
8…….94…….68………Loose....Snug..…..Loose………..Unbanded…..32.4g
9…….94…….68………Loose....Snug..…..Loose………..Unbanded…..32.4g

Notes
Day 3- Feels like the bands are about to where they started out, weight is over a full gram up from starting point.
Day 4 to 9- Cigars stabilized, about same feel as when kept at 69/69. Bands may be slightly looser from my checking them every day.

Then remove the beads, and replace it with an Oasis half full and turned off. I'm putting the unit in turned off, to explore how well the Oasis, controls evaporation from it's reservoir when the unit doesn’t run. Then we’ll do the same tests plus weigh the Oasis, to follow evaporation.

Day…Temp…RH%..... Cigar1…Cigar2…Cigar3……..…Cigar4……….Net Weight…Oasis Weight
10…….96…….68………Loose....Snug..…..Loose………..Unbanded…..32.4g……….421.8g
11…….96…….67………Loose....Snug..…..Loose………..Unbanded…..32.1g……….421.2g
12…...96…….67………Loose....Snug..…..Loose………..Unbanded…..32.1g……….420.6g
13…...97…….69………Loose....Spins..…..Loose………..Unbanded…..32.1g……….419.7g
14…...97…….68………Loose....Spins..…..Loose………..Unbanded…..31.9g……….418.4g
15…...94…….70………Loose....Spins..…..Loose………..Unbanded…..31.8g……….417.0g
16…...95…….69………Loose....Spins..…..Loose………..Unbanded…..31.7g……….415.5g
17…...95…….69………Loose....Spins..…..Loose………..Unbanded…..32.0g……….414.3g
18... These cigars plus control group put into platic bag at room temperature. Numbered randomly 1-8 for testing.


Notes
Day 12 Cigars starting to feel dry, put beeds back in with Oasis.

Finally, we’ll do what matters the most IMO, at the herf at my house on 3/21 I’ll get some people to smoke two cigars side by side, one from the experiment and one from the control group maintained in my regular humidor. I’m mostly curious about draw problems, burn issues and how it changes the taste if at all. All cigars came from the same boxes, so although no two cigars can be expected to be identical, this is as close as we can hope for.

We smoked em, and half the group liked the control group better, half liked the 90+ degree sticks better. I'll contemplate this a while and post my thoughts when I get back from Esteli.

 

[sam a]

wow, great experiment... i look forward to seeing the results.

 

[TheCigarKid]

Damn Bill Nye the Science Guy! I'm looking forward to hear back w/ your results!

 

[dpricenator]

I will be watching this closely.

 

[jbott21]

Wow...I must say this is very impressive. Is it sad that I'm excited about this experiment? I worry quite a bit about my humidor...you hear so many different theories. This will be fun to see

 

[pfm721]

I'm excited to see what happens. Should be interesting to see the results.

 

[lakeside toker]

Damn ,I was way off..I always thought that relative humidity was the sweat that was on your testicles when you got cuaght having sex with your sister-in-law.

Sorry...I had to do it.

 

[rduke10]

you know your a botl when........

 

[strife]

Cool experiment.

One of the things that I'm responsible for at my job is controlling the environment in our library. We had a mold issue once and it cost us a shitload to have the books cleaned and the HVAC system overhauled, we also called in a consultant. He told us that our optimum goal should be 68 degrees at 40-50% RH. However he stressed that the air temperature wasn't the main issue it was the RH that had to stay in that range regardless of the temp swings or there would be issues as far as moisture absorption or drying out was concerned.

The temp swings could break down inks and photo emulsions but he stressed that the room could be 30 degrees or 100 degrees and there would be no paper damage or mold issues if we kept it between 40-50% Rh. I can't see why the same shouldn't hold true for cigar leaf?

 

[GoingPostal]

Great experiment will keep an eye out on the results

 

[jbott21]

Cool experiment.

One of the things that I'm responsible for at my job is controlling the environment in our library. We had a mold issue once and it cost us a shitload to have the books cleaned and the HVAC system overhauled, we also called in a consultant. He told us that our optimum goal should be 68 degrees at 40-50% RH. However he stressed that the air temperature wasn't the main issue it was the RH that had to stay in that range regardless of the temp swings or there would be issues as far as moisture absorption or drying out was concerned.

The temp swings could break down inks and photo emulsions but he stressed that the room could be 30 degrees or 100 degrees and there would be no paper damage or mold issues if we kept it between 40-50% Rh. I can't see why the same shouldn't hold true for cigar leaf?

Intersting as well. You wouldn't feel safe keeping your sticks at that RH would you?

 

[strife]

Intersting as well. You wouldn't feel safe keeping your sticks at that RH would you?

No but that wasn't the point. The point was that the RH should remain constant regardless of temp changes to ensure a proper environment for the books. Paper is a cellulose plant product as is cigars therefor the same should remain true for both as far as a constant RH is concerned.

 

[Mitch]

First Post edited with the first batch of results, they are drying out a bit.

Intersting as well. You wouldn't feel safe keeping your sticks at that RH would you?

Gotham Cigar Museum keeps theirs at 60RH and 60 degrees. Europe tends to agree on lower than 65RH as well and I know some collectors that go as low as 50RH for the ones they don't want to mellow any more.

http://gotham-cigar-museum.com/storage.aspx

 

[strife]

This is like the "Airplane on the treadmill" teaser. The answer is there yet so many people get befuddled by over thinking it.

Whatever the results I'm sure Mitch that you'll really enjoy doing it. No harm in having some fun in the name of science. Speaking of which, I hear that you can take cheap ass vodka, pass it through a Brita water filter a few times and get something as smooth as Grey Goose. :drool:

 

[Virgeinadeaux]

Hell of an experiment. I too am anxious for the results please keep us posted. This mite change the way we all keep our cigars. :thumbsup:

 

[Jfire]

Looks good to me Mitch. One note from my vinos. 64%rh with beads at 68deg and 64%rh at 61 Deg. So at least in my case my beads are always @ 64% in the little but of temp variation that I experiance.(Never needed to use the thermo cooling/ so its a natural temp swing as well) And also in my case 64%rh has always treated my ccs and Ncs just fine.

 

[Mitch]

This is like the "Airplane on the treadmill" teaser. The answer is there yet so many people get befuddled by over thinking it.

Whatever the results I'm sure Mitch that you'll really enjoy doing it. No harm in having some fun in the name of science. Speaking of which, I hear that you can take cheap ass vodka, pass it through a Brita water filter a few times and get something as smooth as Grey Goose. :drool:

I think there was an actual Myth Busters episode on the Vadka and it was busted, not as good.

 

[kockroach]

I think there was an actual Myth Busters episode on the Vadka and it was busted, not as good.

Yep, a vodka expert was able to determine the order of quality from the crap vodka, through the various rounds of crap vodka thru the filter, and the good vodka.

 

[Mitch]

I've already gotten my eyes opened up at day one. In a air and water tight sealed plastic container, cigars can dry out, just from a temperature change, when it gets warmer. The amount of moisture in the container had to stay constant, but the cigars dried out as humidity went into the air. So, it seems that air can not only hold more water vapor at higher temperatures, it wants to and will draw moisture from cigars to do so.

The opposite should hold true as well, when the air cools it will force water vapor from it, that is why you can't get even close to 99RH at 60 degress. So, the way I think of this right now is, air has a comfort zone of how much water vapor it wants to hold, and if the RH drops too low or gets too high, it will use your cigars to try to ballance itself.

This may explain the trouble I had with using an Oasis, back before temp control days on a humidor under an AC vent. I thought that was the coldest place I could find to prevent beetles, but I had a problem with over humidification. Lookinig back, it makes sense, the Oasis can add humidity, but not take any away, so when the temp rises it added, but when the temp dropped, it could not absorb it. The problem was gone with beads in a day or two. So, if you have temperature swings, you need to make sure you have a humidification device that works both ways.

Seem like sound logic so far?

 

[Hardcore]

Nice Mitch.