Max gals fermenting in Basement?

[derunner]

Currently, I have 16 gals of skeeterpee fermenting in the basement. I've done two 6 gal ferments several times and never really noticed it much, but I am wonder if there is a limit to how many gals I should ferment in a closed basement with little ventilation? I have a cold this week, so maybe that is making me notice it more, but I am wondering if I get 5 juice buckets in May if this is too much at once, especially from a CO2 perspective?

What is the most you have fermented in a closed space with little ventilation?

Should I be installing an exhaust fan?

 

[sour_grapes]

I recalled an earlier thread on this same subject: http://www.winemakingtalk.com/forum/f6/fermenting-fumes-hazard-42135/

And here was my response on that thread:

I think you may be confusing CO and CO2 (carbon monoxide and carbon dioxide).

Small amounts of CO can harm or kill you. CO2 can kill you, but only by asphyxiation -- i.e., lowering the amount of O2 in the air to unsafely low levels.

One thing we have going for us is that we do have built-in CO2 detectors in our bodies. The condition that causes you to feel short of breath and makes you want to breathe (like when you are holding your breath underwater) is not lack of O2 in your blood, but rather an excess of CO2.

If you went into a room that was low in O2 because it was filled mostly with N2 or Ar, you wouldn't feel it -- you would just eventually faint (from lack of O2) and then die. But if you went into a room that was low in O2 because it was filled with CO2, you would be gasping for breath. Thus, although you can be asphyxiated by CO2, it is the hardest substance in the universe to be accidentally asphyxiated by.

 

[JohnT]

It all really depends on the size of your basement and also how aggressively your wine is fermenting.

I normally play it safe by having a box fan circulate the air for a few minutes with an open door or window for a source of fresh air. I would run the fan for a few minutes before I spend any long amount of time in there.

 

[sour_grapes]

Oh, I have one more way for you to think about it. Think about how much sugar is in your batch. If you have 16 gal., you probably have about 30 lbs. of sugar in there. All of that sugar is going to be converted to ethanol and to CO2.

About 2/3 of the carbon in the sugar goes to ethanol, and 1/3 to CO2. So picture 1/3 of thirty pounds, that is, 10 lbs of sugar. You can think of, say, two 5 lbs. sacks of sugar.

Now imagine that these are candles. That is, you had candles the same size as the sugar sacks. Would you be willing to burn these candles in your basement, over a few days, until they are all gone?

That would be about the amount of CO2 released during your fermentation, for better or for worse.

 

[seth8530]

Not to nit pick put its closer to 50% Ethanol and 50% Co2 by mass if I remember some of my prior work properly.. Either way, a little ventilation would not hurt.. Worst case scenario you might manage to flush some radon out of your basement (;

 

[sour_grapes]

Not to nit pick put its closer to 50% Ethanol and 50% Co2 by mass if I remember some of my prior work properly..

That may be true, but that does not change the fact that that 2/3 of the carbons in the sugars wind up in ethanol, and only 1/3 wind up in CO2. In my "burning candle" analogy, obviously, additional reactants come from the air. I was trying to approximate how much starting organic stuff you would need such that, when combined with air (i.e., burned), it would produce a comparable amount of CO2 as fermentation would.

In your example, the O to form the CO2 comes from the sugar itself. If I told him to mentally cut the amount of sugar in half, then think of this as a candle, it would combine with air to produce MUCH MORE CO2 then the total mass of the sugar.

I was approximating that the density of granulated sugar (not crystalline sugar, but including the empty space between granules) would be similar to the density of wax. I just checked, and this indeed turns out to be the case.

You have made me realize that I should really have divided by 7.5 instead of 3. (That is, the weight of 1/3 of the carbons divided by the weight of the whole molecule.) So, I guess we should think of a candle that is 1/7 the size of the 30 lbs of sugar, so, the size of a 4 lb sack.

 

[vacuumpumpman]

Currently, I have 16 gals of skeeterpee fermenting in the basement. I've done two 6 gal ferments several times and never really noticed it much, but I am wonder if there is a limit to how many gals I should ferment in a closed basement with little ventilation? I have a cold this week, so maybe that is making me notice it more, but I am wondering if I get 5 juice buckets in May if this is too much at once, especially from a CO2 perspective?

What is the most you have fermented in a closed space with little ventilation?

Should I be installing an exhaust fan?

I personally have 24 gallons fermenting right now -
My house is definitely not air tight - I personally would not worry over it.

 

[seth8530]

That may be true, but that does not change the fact that that 2/3 of the carbons in the sugars wind up in ethanol, and only 1/3 wind up in CO2. In my "burning candle" analogy, obviously, additional reactants come from the air. I was trying to approximate how much starting organic stuff you would need such that, when combined with air (i.e., burned), it would produce a comparable amount of CO2 as fermentation would.

In your example, the O to form the CO2 comes from the sugar itself. If I told him to mentally cut the amount of sugar in half, then think of this as a candle, it would combine with air to produce MUCH MORE CO2 then the total mass of the sugar.

I was approximating that the density of granulated sugar (not crystalline sugar, but including the empty space between granules) would be similar to the density of wax. I just checked, and this indeed turns out to be the case.

You have made me realize that I should really have divided by 7.5 instead of 3. (That is, the weight of 1/3 of the carbons divided by the weight of the whole molecule.) So, I guess we should think of a candle that is 1/7 the size of the 30 lbs of sugar, so, the size of a 4 lb sack.

Yeah, like I said I was not trying to nit pick. Your example is perfectly fine. I guess something to keep in mind is that 1kg of Co2 has a much bigger volume than say 1kg of sugar due to density considerations. However, your example is fine and clever.

 

[Geronimo]

Normal air is 78% nitrogen, 20% oxygen, 1% argon and traces of other gases (including 0.03% CO2).

You will not produce 1 cubic foot of CO2 from 6 gallons of must. The CO2 will disperse rapidly into the open air. If somehow you filled your basement 3/4 full of must and rapidly fermented it in a few hours, then you could be in trouble. Remember, you have to displace a lot of air (and your house is air tight) to reduce the O2 levels to choke to death. Your house would need to become a giant fermenter with an airlock on top.

You have no worries IMO.

 

[sour_grapes]

Yeah, like I said I was not trying to nit pick.

Okay, good. Often, when someone starts by saying "Not to nitpick..." what they mean is "I am going to nitpick." Glad to hear that was not the case.

 

[seth8530]

Normal air is 78% nitrogen, 20% oxygen, 1% argon and traces of other gases (including 0.03% CO2).

You will not produce 1 cubic foot of CO2 from 6 gallons of must. The CO2 will disperse rapidly into the open air. If somehow you filled your basement 3/4 full of must and rapidly fermented it in a few hours, then you could be in trouble. Remember, you have to displace a lot of air (and your house is air tight) to reduce the O2 levels to choke to death. Your house would need to become a giant fermenter with an airlock on top.

You have no worries IMO.

I would not say no worries. I believe that this is an issue which should be taken seriously; however, if the issue is properly understood it should not be a problem. Take for instance, if you ferment 30 lbs of sugar around 15 lbs of that will get turned into Co2. Co2 has a density of close to 2kg/m^3 and 15 lbs is roughly 7 kg. Thus you would get roughly 3.6 m^3 of Co2.. That is quite a bit. Just for reference m^3 is equal to around 35 cubic feet.

I do agree that in a leaky room this is not such a big issue, however if you were fermenting in something like a deepfreezer, or a fridge this is an issue that needs to be considered and precautions will need to be taken.

Okay, good. Often, when someone starts by saying "Not to nitpick..." what they mean is "I am going to nitpick." Glad to hear that was not the case.

Yep yeps, I meant it for reals this time lol.

 

[JohnT]

I remember a time when I did not pay attention to the levels of CO2 and simply opened a door for ventilation.

I quickly discovered that this was not nearly enough. I would go to do a punchdown, and within minutes I became very shaky and started to seat. When I started feeling dizzy, I had enough sense to step outside for a bit.

After experiencing this, and also reading about a number of poor folks that have died in just this scenario, I purchased a box fan that I place in front of my open door to force fresh air into my winery. I let this run several minutes before I begin punching down.

I do not really care about the math. CO2 is poison and good ventilation can only help you.

 

[Runningwolf]

I have had at least 150 gallons going at one time in my basement at the same time. What a year!!!!

 

[Geronimo]

CO2 is poison

You make it sound like drinking a beer too fast will kill you. CO2 is NOT poison, it's an inert gas and harmless. The only way CO2 production can kill you is from asphyxiation.

Large wineries and breweries have to take precautions and use air exchangers.

A 6 gallon fermenter won't produce enough CO2 for a home brewer to worry at all.

If you have a tiny room packed full of fermenters and have no ventilation then I guess you're special I have small pets and none of them have gotten the least bit dizzy.

 

[derunner]

There are conflicting post on this subject. Clearly commercial wineries and brewers have to worry as people have had issues cleaning out tanks for instance. And farmers have had problems in silage pits/silos from fermentations. It does not take a lot of CO2 for people to start feeling uncomfortable. CO2 is also heavier than air so it is not naturally going to mix with air in upper floors if you ferment in a tight basement. So while perhaps not life threatening, I am going to see if there is some sort of fan unit I can put into my small basement windows during the weeks I am fermenting a lot. like I said I never noticed 2 buckets, but I am planning to do 5 at once so a little airflow would be nice.

 

[Geronimo]

I think it's important to note that no one that has responded about the "dangers" of CO2 production has any test data regarding concentrations and everything that's been said is purely anecdotal. No one has a single example of any home brewer that's been harmed, directly or indirectly (such as their pet Pomeranian died and the autopsy indicated asphyxiation).

So if you have a basement that air normally stagnates in (no water heater, furnace, clothes drier, etc) and no windows, fans, etc... and you plan to make a lot of batches at the same time, then throwing a box fan in the basement isn't a bad idea. It must stink pretty bad down there anyway!!

 

[derunner]

Here are some links I have found since people were asking for links. The risk is more than just the lack of oxygen. Usually CO2 levels that raise a few percent only drop O2 levels by a small amount that you would not notice. I'm not suggesting there is a great risk, but I think it would be possible you could have some issues which hopefully cause you to leave the area and ventilate if you have a lots of ferments. It seems the ones were people were seriously hurt/died were family wineries etc.

http://www.analox.net/carbon-dioxide-dangers.php

https://www.eiga.eu/fileadmin/docs_...siological_Hazards_Not_just_an_asphyxiant.pdf

From this paper it looks like you get 50% by weight of co2 and alcohol from fermenting sugar. So for 30 lbs of sugar you would get 15 lbs of co2.

http://books.google.com/books?id=Tm...=c02 from fermenting a pound of sugar&f=false

From another link 15 lbs of c02 would be .2426 cubic meters per pound of co2. so 3.639 cubic meters of co2 or 118 cubic feet of c02 vs 2000 cubic feet in the room. Now it takes 3-5 days for most of that sugar to ferment so hopefully some of that mixes with other air, but I have nothing to say how much would mix and flow up a stairway. It was enough for my wife to notice when she entered the house on the first floor so some mixing occurs. But normally she does not notice the fermentation unless she goes to the basement.

And here is an osha link to a warning about a brew on premise employee dying from exposure to CO in a basement where many batches had started fermentation the week before. Parmedics were also effected.

http://www.labour.gov.on.ca/english/hs/pubs/alerts/i35.php

 

[vacuumpumpman]

I found a nice link to a portable Carbon Dioxide meter
http://www.co2meter.com/