Silly question - co2 in a small room

[RaymondReddington]

I have two 4.5 litre batches of Strawberry Cider fermenting in my bedroom. Are the gasses that are being released from them harmful in any way and should I keep the bedroom window open as I sleep?

Thanks

 

[user 125772]

No, not harmful. How does it smell?

 

[RaymondReddington]

No, not harmful. How does it smell?

It doesn't really smell of anything unless I smell the airlock and even then it's a fruity smell

 

[Twotaureanbrewing]

Lol, funny but legit. Gaseous molecules bounce off each other millions of times per second even without air movement.

http://colinb-sciencebuzz.blogspot.com/2010/01/if-co2-is-so-heavy-why-doesnt-it-sink.html

 

[Singletrack]

No problem. If you wake up dead, you'll realize it immediately.


...but I wonder which produces more CO2, 9 litres of cider, or a snoring dog.

 

[JONNYROTTEN]

Close the window duct tape the door and plant some weed...it's a win win:fro:

 

[thelema5]

While CO2 is a poisonous gas, the amount being produced is so minuscule that it doesn't really pose any risk. Opening a can of soda will release more of the stuff into your room than a night of fermentation emissions, so I wouldn't worry about it. You release much more CO2 while breathing than your cider does.

If you were smelling hydrogen sulfide (rotten egg smell) I'd be a bit more concerned- it's highly poisonous, corrosive, and explosive. I had a cider which was producing what I thought was a massive amount of H2S, so I sealed the airlock in a large trash bag.

While this stopped the stench from reaching my nose, it also gave me an appreciation of just how little gas is actually produced during fermentation- over the course of two weeks I'd estimate a total volume of about 2 liters of CO2 and H2S was collected.

This is a small enough volume to be essentially harmless when released slowly over time into a ventilated room.

 

[Caliper]

Co2 is heavier than air anyways. So, unless you are surrounded by fermenting carboys while sleeping on the floor...

 

[Singletrack]

While CO2 is a poisonous gas, the amount being produced is so minuscule that it doesn't really pose any risk.

I had a cider which was producing what I thought was a massive amount of H2S, so I sealed the airlock in a large trash bag. While this stopped the stench from reaching my nose, it also gave me an appreciation of just how little gas is actually produced during fermentation- over the course of two weeks I'd estimate a total volume of about 2 liters of CO2 and H2S was collected.

I don't know about cider, but beer produces a much larger amount of CO2 during fermentation. According to the article in the link below, a beer with an OG of 1.060 and 85% attenuation produces nearly 18 cubic feet of CO2. Why would there be such a big difference with cider?

https://lifefermented.wordpress.com/2014/01/22/how-much-co2-is-produced-from-brewing/

 

[Singletrack]

Co2 is heavier than air anyways. So, unless you are surrounded by fermenting carboys while sleeping on the floor...

Yes, CO2 is heavier than air. However, it readily diffuses into the ambient air, so there would not be a blanket of CO2 on the floor. As some bright person put it, if CO2 did not diffuse in the air, the earth would have a blanket of CO2 at its surface, and we would suffocate.

 

[thelema5]

I don't know about cider, but beer produces a much larger amount of CO2 during fermentation. According to the article in the link below, a beer with an OG of 1.060 and 85% attenuation produces nearly 18 cubic feet of CO2. Why would there be such a big difference with cider?

https://lifefermented.wordpress.com/2014/01/22/how-much-co2-is-produced-from-brewing/

I can only assume there's either a problem with the calculations or a difference in how the fermentation occurs in beer. I captured nearly all the gas produced by 6 gallons of cider fermenting for several weeks with an airtight seal around an airtight container, and this was the result:

That doesn't look like more than a couple liters of gas, to me, and certainly isn't close to 18 cubic feet. By way of contrast, 18 Cubic feet of gas looks like this:

The contact point around the airlock in my example was sealed tightly with first a wire-tie, and then with three applications of airtight adhesive tape. CO2 is heavier than air so it wouldn't have leaked from the seal, and even if it hadn't been perfectly airtight I'd have noticed the Hydrogen Sulfide smell, as this rig was only two feet from my desk.

I'm an uneducated hick so those calculations don't mean anything to me. But there's theory, and there's observation. I'm sure there are a thousand variables which can affect the total output, but my personal observation of the volume of gas produced during cider fermentation seem to support fewer emissions than the linked article suggests.

I would be very interested in seeing the author of that article conduct an actual empirical experiment where he attempts to demonstrate that much gas production in a real-word application.

 

[EarthwormJim]

I can only assume there's either a problem with the calculations or a difference in how the fermentation occurs in beer. I captured nearly all the gas produced by 6 gallons of cider fermenting for several weeks with an airtight seal around an airtight container, and this was the result:

...

I would be very interested in seeing the author of that article conduct an actual empirical experiment where he attempts to demonstrate that much gas production in a real-word application.

I don't think 18 cubic feet is unreasonable. The amount of air in the ball in the picture is likely closer to 110 cubic feet than 18. 18 would fill a ball a little over 3 feet in diameter. Assuming the man in the pic is average height, the diameter of that ball is at least 6 feet.

I don't know that your cider fermentation is a very good example. You said you put the bag on because of the smell that was coming from the fermentor. For you to have noticed the odor, it would have to have been fermenting already and have gotten far enough for there to be a noticeable amount of gas released. At that point more than half the sugar could have been gone already. Also without knowing your SG, it would be hard to estimate how much gas you should expect. Because of the weight of the bag, the gas would be under more pressure and occupy less space and I am also sure there is a lot more gas in the spaces outside of the main bulge you are measuring.

I apologize if I sound argumentative. I am not trying to start an argument, just further the conversation. I do believe the 18 cubic feet is probably close. It sounds like a lot but really isn't that much. It would be nice to see a controlled experiment though.

 

[MarshmallowBlue]

for science, blow through an airlock with water and see just how insane it is.

You're all good, as others have said.

 

[gregbathurst]

That black plastic bag was not designed to hold gas, it would be fairly permeable and probably has pinprick sized holes which would let gas out. The theories that describe gas behaviour have been known for hundreds of years and have been well proven, you don't need to do "experiments" to prove or disprove them.

CO2 is quite dangerous and has caused many fatalities in wineries and other places. Though a normal homebrew fermentation in a room won't kill you it is always best to be cautious and not take risks.

 

[Caliper]

Yes, CO2 is heavier than air. However, it readily diffuses into the ambient air, so there would not be a blanket of CO2 on the floor. As some bright person put it, if CO2 did not diffuse in the air, the earth would have a blanket of CO2 at its surface, and we would suffocate.

There are also air currents that move our atmosphere around. Wine brewers rely on a CO2 blanket to keep their initial fermentation free of oxygen, so there is some blanket effect when releasing straight CO2.

Either way, if we take the 18ft^3 of CO2 proposed, that would only represent 2.25% of the volume of a small 10'x10'x8' room over the entire fermentation.

 

[bernardsmith]

I don't know how many cubic feet of CO2 cider produces compared to beer but I do know that half the weight of all the fermentable sugar is converted to alcohol and half the weight is converted to CO2. So if you have 2 lbs of sucrose/fructose and or glucose in your cider you will produce 1 lb of alcohol and 1 lb of CO2 and if you have 10 lbs of the sugar you will produce 5 lbs of CO2. That may not be enormous - but it ain't chump change.. and much of it of it will remain dissolved in the alcohol unless you actively remove it or it slowly dissipates over time..

 

[FloppyKnockers]

I'd be more worried about N2 O2 H2 CO2 CH4 from the brewer.