co2 Tank Safety in the House

[daworldisblack]

Anyone read articles on how safe or unsafe this is? Looking to be referred to articles that cover this topic. I couldn't find anything but perhaps you have come across an article if you did research on this topic before? Thanks!

[exv152]

I found this article. I keep the three 10 lbs tanks I have in the basement, where it's always around 68-72ºF, because the liquid expands in warmer temps. Anything above 90ºF is apparently asking for trouble. http://www.reefscapes.net/articles/breefcase/co2_tanks.html

[daworldisblack]

Sweet thanks.. Also found this thread: http://www.plantedtank.net/forums/showthread.php?t=91909

[exv152]

Tom Barr has a good point, every restaurant, convienence store, bar etc, has pressurized co2 for soda and beer. I'm sure they sometimes deal with hot temperatures during the summer months, but you never hear of anyone being killed by co2 tanks exploding. I imagine that if the temperature rose so high and the tank couldn't hold the pressure, the regulator safety valve would give out first before the tank would rupture. So you might find your tank empty but that's hopefully the worst that could happen. 

[magnosis]

while I lack concrete articles to back this up, I was faily paranoid when I setup my pressurized system at home especially with a baby on the way. I've read and heard from other members that a 10lbs bottle emptying inthe house overnight would Not be a hazard to your health. you may have read my recent post about a regulator safety valve opening and letting go gas at high pressure. I got dizzy for a bit because I got very close but this is an extreme case and even there, I cracked a few windows open and let the air circulate for a couple hours and that was it. it did not detract me from using pressurized co2 again.

remember that this is far less dangerous thant carbone monoxide.

also you are doing well to gather information and take minimum safety measures before & while setting it up some people put a little too much trust in others and go blindly about it.

Sent from my SGH-T989D using Tapatalk 4 Beta

[Stussi613]

This article talks about various levels of CO2 above the 350ppm that is normal in the air we breathe.

http://www.livestrong.com/article/218581-the-effects-of-inhaling-carbon-dioxide-gas/

The question you have to ask yourself is whether a 10lb bottle of CO2 is going to triple the amount of CO2 in your house, or in the room the canister is in if its 100% sealed off from the rest of the house for long enough to cause the type of damage that prolonged exposure has been shown to cause.

I'm going to say not likely, but I'm no rocket surgeon.

[daworldisblack]

Thanks guys! I am not so concerned about the co2 concentration - my landlord thinks it might explode etc. I knew its safer then he thinks but I needed articles/references to forward. Simply saying all the other fish people do it and say its safe is not going to cut it  

[exv152]

If the tank were to ever come into contact with fire, then yeah it's a potential bomb. Just look up "co2 bomb" on youtube and you'll see a ton of videos of teens blowing up 20oz tanks, or 88g tanks for fun. But tell your landlord the tanks are hydro tested every five years to be certified for refilling, and are tested under extreme pressure (I believe it's up to 3000 psi). It's extremely unlikely they will go off on their own, and the fact that you're using a regulator is a good thing. It means the tank is not being stored closed, it actually has a safety valve that will release any excess pressure.  

[magnosis]

I did a little more digging up on CO2 concentrations and the risks to human health.

Here's what I came up with. Someone double check my calculations, I've redone then 3 times but I'm a computer engineer, not a chemist, physics major or doctor

CO2 concentration spike from a 10lbs bottle emptied in a room
- CO2 has a molecular weight of 44.01 g/mol
- Based on the ideal gas law (PV=nRT), at 24°C (297.15K) & standard atmospheric pressure (1 atm), 1Kg of CO2 occupies 553.8 Liters of space
- Therefore, 10lbs of CO2 occupy 2512 L, or 88.71 cubic feet (at same temp & pressure)
- My room is ~28 ft x 13ft x 7.75ft = ~2821 cubic feet
- A 10lbs CO2 would increase the room concentration by ~3.15%

Normal concentration
- Carbon dioxide content in fresh air varies between 0.036% and 0.039%

Effects of CO2 inhalation
- At 0.06%, the air feel heavy, stuffy, more difficult to breathe
- At 0.1%, the air is difficult to breathe; possible symptoms include heart rate increase, headaches, hyperventilation, fatigue, sweating and hearing impairment. Immediate removal to fresh air strongly advised
- At 0.1% to 0.5%, it is considered potentially dangerous to your health.
- At 1.5% to 3%, severe symptoms will manifest within 1-2 hours of of exposure: dizziness, nausea, shaking/twitchy muscles, hallucinations, vomiting, unconsciousness and asphyxia.
- Long term exposure can result in nerve breakdown & cardiovascular conditions such as acidosis (blood ph dropping) causing permanent cell damage.

Conclusions
- With proper ventilation and a normal sized room, there isn't much risk.
- If you start to feel symptoms, immediately go outside & breathe fresh air. Then, crack open a window & circulate fresh air in the room
- Never put a pressurized CO2 system in a bedroom. If the tank empties itself while you sleep and you don't notice, in a relatively small room, it could be a serious hazard.

Sources:
Story & calculations: http://www.thereeftank.com/forums/f6/co2-leak-kills-woman-173476.html
Toxicity: http://www.livestrong.com/article/218581-the-effects-of-inhaling-carbon-dioxide-gas/
General CO2 info: http://en.wikipedia.org/wiki/Carbon_dioxide#Human_physiology
Ideal Gas Law: http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/idegas.html
Henry's Law for CO2: http://en.wikipedia.org/wiki/Henry%27s_law
Units & basic gas properties: http://google.com
Volume of CO2: http://www.umsl.edu/~biofuels/Energy%20Meter%20labs/How%20much%20volume%20does%20a%20kg%20of%20CO2%20occupy.pdf

[exv152]

Hey Rah, I would also take a quick look through your rental contract to see if there's anything in there that stipulates you cannot store pressurized cylinders on the rental property. Or some other wording to that effect. Chances are you won't find it, and he can't do much about it.

[Stussi613]

Mangosis, the math is right, but the percentage increase is only applicable if the bottle is released into a completely sealed room, and only if the gas is all released at the same time. Osmosis would assume that an equal amount of gas would leave the room through any/all possible places where it can equalize.

I do agree though, wouldn't want this in my bedroom.

[magnosis]

Yes, yes of course. It is common sense that the room should have decent air circulation and exchange as is usually the case. Otherwise we would certainly notice a lot of moisture generated from tank water evaporation.  If you don't, then your air exchange is probably sufficient.

Our home was built in 2007 and felt like a ziploc bag until we installed an air exchanging unit. Before that, every window in the house was covered with condensation in the morning, to the point of collecting mold over time. It was pretty intense. On the other hand, this was good for reducing heat loss Installing a heat recovery air exchanger was an excellent investment.