Rank: Forum user 
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I have been asked if we can store Dry ice in a 200, 000 sq ft freezer warrehouse, i have spoken to some suppliers who said no mainly because it could lower the temperature and on the grounds of build up of carbon dioxide, the freezer has a number of blowers that move the cold air around and there are dock doors etc that would allow carbon dioxide to escape, any ideas on who would be able to do an idependent assessment?
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Rank: Super forum user
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You will have to do some process/engineering calculations.
Converting the potential of solid Co2 to convert to an equivalent gas volume.
The density of dry ice is about 1.5g/ml, so 1cc is about 1.5g of Co2.
You will then need to work out how many Moles of gas you have.
Then apply the gas laws V=nRT/P
Moles
Xx Co2 x (1 mole Co2/44g Co2)
44g in a Mole
Xx = Co2 you have.
You will then have to work out if the volume of Co2 will become toxic in the volume of the ware house. I wouldn't expect all of the dry ice to convert to gas quickly.
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Rank: Super forum user 
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Why do you feel the need to attempt to keep/ store it? (-78 C?)
The product is ideally suited for just-in-time delivery and use itself is time-limited.
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Rank: Super forum user
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If you decide to proceed with the idea, then bear in mind that carbon dioxide is toxic, and is NOT a simple asphyxiant. (see http://www.ivhhn.org/ind...p;view=article&id=84)
1 kg of dry ice will give you approximately 0.54 cubic metres of gas.
0.5% is the exposure limit (see http://www.hse.gov.uk/pubns/priced/eh40.pdf). Above about 7% it can cause death.
You don't say how much you want to store.
You can buy CO2 alarms (they are marketed largely for pubs).
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Rank: Super forum user
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Jane is correct - in high concentrations Co2 is toxic, its acts differently than simple a oxygen replacement. To work out how much/quickly the oxygen in the warehouse is replaced by the Co2 is actually quite a difficult calculation as there are so many variables. Conversion rate of dry ice to gaseous Co2,ventilation in the warehouse, local congestion/racking etc will affect dispersion paths of the Co2. From memory you end up doing differential calculus calculations - which gets to be fun. On a practical note you need to ensure you have good ventilation to prevent oxygen depletion, install gas detectors to check O2 leved to ensure the incoming ventilation is good to prevent oxygen depletion, gas detectors Why do you want to store such large amounts of dry ice? It would seem sensible to make it on demand, as making too much is a waste of money/time/energy as it will be constantly converting back to gas.
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Rank: Super forum user
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An oxygen monitor is not adequate in this situation. The carbon dioxide will reach a dangerous level before the oxygen monitor is triggered. You need a CO2 monitor.
Edited by user 25 February 2017 10:52:54(UTC)
| Reason: altered word as I haven't done all the calculations
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Rank: Super forum user
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On the question of oxygen monitors. The ones we have always used are set to alarm when the oxygen level has fallen to 19.5%.
If the gas leaking into the workplace is CO2, then by the time the oxygen alarm sounds there is 7% carbon dioxide in the room, massively above the exposure limit and potentially very dangerous.
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Rank: Forum user
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Well, a typical question and interesting too. I think this question is very much trending because i have read 2 more question which is related to store ice. Now comes to your discussion, i think you just need to maintain the quantity of oxegyn and check it after some time interval that it may not decrease. Also i am searching on that what happened if quantity of oxygen increase from a specific leve but i did not find a satisfactory answer yet but i will find it sonn and will share it with you.
Thank you!
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Rank: Super forum user
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Do not store dry ice in a freezer. I know someone who did it once and we almost lost two people (they begin to pass out from lack of oxygen/CO2 toxicity). As has been pointed out, dry ice sublimes at -78C while freezers tend to work at -20C which means dry ice will continue to melt even in the freezer so there is no point storing it in freezer. If you want to store, dry ice then you should keep it in an insulated chest. If you are getting through loads of dry ice then you will need to think about installing a dry ice
making rig.
But whatever you do not store it in any freezer even a chest freezer is a no-no.
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