Dry Ice???
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REALLY dangerous
Dry ice evaporates to carbon dioxide, which is heavier than regular atmospheric air. Within a boat cabin, it would tend to build up inside the cabin, displacing the oxygen. Definite risk of suffocation. I wouldn't recommend it, even if you think you have adequate cross-ventilation.
Dry ice evaporates to carbon dioxide, which is heavier than regular atmospheric air. Within a boat cabin, it would tend to build up inside the cabin, displacing the oxygen. Definite risk of suffocation. I wouldn't recommend it, even if you think you have adequate cross-ventilation.
Amazzzzinnnng stuff that dry ice
Makes you wonder how it knows not to drip all over the place. Smart stuff that dry ice. And it cold as 'ell
Makes you wonder how it knows not to drip all over the place. Smart stuff that dry ice. And it cold as 'ell
Our H28 had a cooler that I used dry ice...
in when we left on cruises. I found the most effective way was to lay down a bed of two bags of chunk ice, lay the dry ice (20 pounds lasted about a week, 30 pounds almost two weeks) on the bed of chunk ice then cover the dry ice with another two bags of chunk ice, which acts as an insulator. Never had a problem, but you do need to keep the boat well ventilated. Terry
in when we left on cruises. I found the most effective way was to lay down a bed of two bags of chunk ice, lay the dry ice (20 pounds lasted about a week, 30 pounds almost two weeks) on the bed of chunk ice then cover the dry ice with another two bags of chunk ice, which acts as an insulator. Never had a problem, but you do need to keep the boat well ventilated. Terry
Read Post #1
Post #1 is spot on. The gas that is given off is odorless, colorless, and can kill you. Other than that, yes, it is cold. By the way, it will carbonate whatever is in the cooler or fridge if they are not gas-tight, f.e., sealed plastic container. Good post, Mike.
Post #1 is spot on. The gas that is given off is odorless, colorless, and can kill you. Other than that, yes, it is cold. By the way, it will carbonate whatever is in the cooler or fridge if they are not gas-tight, f.e., sealed plastic container. Good post, Mike.
Somewhat off topic but
I often wondered if you could put an aluminum plate or coil in the ice box and squirt liquid CO2 through it and then discharge it overboard. Like piping a CO2 fire extinguisher in a drilled port through a thick aluminum plate so the liquid vaporized in the drillings and then vented overboard. I don't think it would take much to cool the plate, and aluminum stays cold for a long time, relativly speaking. CO2 cylinders are cheap and they hold a lot of gas. I would never do this but I often wonder if it would work.
I often wondered if you could put an aluminum plate or coil in the ice box and squirt liquid CO2 through it and then discharge it overboard. Like piping a CO2 fire extinguisher in a drilled port through a thick aluminum plate so the liquid vaporized in the drillings and then vented overboard. I don't think it would take much to cool the plate, and aluminum stays cold for a long time, relativly speaking. CO2 cylinders are cheap and they hold a lot of gas. I would never do this but I often wonder if it would work.
Simply dont put dry ice inside the plastic bag
that you tie over your head. Just keep some ventilation when you use it. An 8lb. block of dry ice does 'wonders' to keep the fridge cold. I dont sleep down in the bilge where the CO2 will accumulate - natural diffusion with ambient air takes care of the 'problem'. Just dont 'seal' the boat up tight if you use dry ice.
that you tie over your head. Just keep some ventilation when you use it. An 8lb. block of dry ice does 'wonders' to keep the fridge cold. I dont sleep down in the bilge where the CO2 will accumulate - natural diffusion with ambient air takes care of the 'problem'. Just dont 'seal' the boat up tight if you use dry ice.
RichH, if you've done it and lived through it
then either the rate of gas production from the dry ice was very slow or you had sufficient cross-ventilation. However..... For those with weak stomachs, read no further! In biomedical research, one acceptable means of humanely euthanizing rodents is to place them in an aquarium-like container filled with CO2 gas. The normal and proper use is to seal the container, but many technicians have found that the CO2 is heavy enough, and diffusion/dilution with ambient air is slow enough, that you can leave the top off the aquarium and still have a pretty effective killing system (leaving the top off makes it easier to keep adding rodents). The moral of the story is that I don't trust the rate of diffusion with ambient air as my safety margin, even if the cabin is open.
then either the rate of gas production from the dry ice was very slow or you had sufficient cross-ventilation. However..... For those with weak stomachs, read no further! In biomedical research, one acceptable means of humanely euthanizing rodents is to place them in an aquarium-like container filled with CO2 gas. The normal and proper use is to seal the container, but many technicians have found that the CO2 is heavy enough, and diffusion/dilution with ambient air is slow enough, that you can leave the top off the aquarium and still have a pretty effective killing system (leaving the top off makes it easier to keep adding rodents). The moral of the story is that I don't trust the rate of diffusion with ambient air as my safety margin, even if the cabin is open.
Mike ----
By your definition any large enclosed area .... auditorium, theater, etc. would be a deathtrap ... as all those contained 'organisms' are just seething with respirational CO2 !!!!! ;-)))))) Just treat CO2 in the fridge box just like you had a large bulkhead heater going full blast and all will be OK.
By your definition any large enclosed area .... auditorium, theater, etc. would be a deathtrap ... as all those contained 'organisms' are just seething with respirational CO2 !!!!! ;-)))))) Just treat CO2 in the fridge box just like you had a large bulkhead heater going full blast and all will be OK.
I'm
in the camp with Terry and Rich. Used to use it in much the same way Terry describes on my Morgan/Catalina 43 back in the 90's. It had no refrig; just a "cold" box. A block of ice won't last more than about 2-3 days. For longer cruises, I used it like Terry with no ill effects. As Rich says, just keep the boat ventilated; which isn't difficult during the Summer w/o A/C. Merry Christmas all... B back after the 5th... Taking L'Attitude over to the Bahamas Thursday
in the camp with Terry and Rich. Used to use it in much the same way Terry describes on my Morgan/Catalina 43 back in the 90's. It had no refrig; just a "cold" box. A block of ice won't last more than about 2-3 days. For longer cruises, I used it like Terry with no ill effects. As Rich says, just keep the boat ventilated; which isn't difficult during the Summer w/o A/C. Merry Christmas all... B back after the 5th... Taking L'Attitude over to the Bahamas Thursday
An Experiment
Let's settle this with a simple experiment: - Start with a complex container, around 12 by 35 feet, with the only openings in the top of the container. - Begin the release of a heavy, suffocating gas in quantities that may, or may not be sufficient to fill the container, depending on conditions we do not understand. - Occasionally include a fan which has an unknown impact on the distribution or evacuation of the gas. - Conduct a number of trials, through varying weather, often including dead calm conditions overnight. - Put the gas sensors several feet below any of the lowest overflow point from the container (the companionway, for instance.) - Oh, yeah - the sensors are me, and one or two other people I care a lot about. Be sure they sign the waivers, since a one or more will die if the test has the predicted outcome. You get the picture. We spend a lot of time on this site discussing our response to, or preventing conditions that will lead to discomfort, injury, or damage to our boat. This CO2 guessing game results in death if we lose! The proper precautions for boosting refrigerator or cold storage performance with dry ice, are the same as for propane: Ensure that any leak or overflow will drain overboard, and provide sensors in the cabin to safeguard the crew. The fact that a couple of us have conducted this experiment a couple of hundred times gives me no confidence. I'm happy buying some more ice, or installing a refrigeration unit. David Lady Lillie
Let's settle this with a simple experiment: - Start with a complex container, around 12 by 35 feet, with the only openings in the top of the container. - Begin the release of a heavy, suffocating gas in quantities that may, or may not be sufficient to fill the container, depending on conditions we do not understand. - Occasionally include a fan which has an unknown impact on the distribution or evacuation of the gas. - Conduct a number of trials, through varying weather, often including dead calm conditions overnight. - Put the gas sensors several feet below any of the lowest overflow point from the container (the companionway, for instance.) - Oh, yeah - the sensors are me, and one or two other people I care a lot about. Be sure they sign the waivers, since a one or more will die if the test has the predicted outcome. You get the picture. We spend a lot of time on this site discussing our response to, or preventing conditions that will lead to discomfort, injury, or damage to our boat. This CO2 guessing game results in death if we lose! The proper precautions for boosting refrigerator or cold storage performance with dry ice, are the same as for propane: Ensure that any leak or overflow will drain overboard, and provide sensors in the cabin to safeguard the crew. The fact that a couple of us have conducted this experiment a couple of hundred times gives me no confidence. I'm happy buying some more ice, or installing a refrigeration unit. David Lady Lillie
No way, Ross
Dry ice concentrates a whole lot more CO2 than a candle will produce burning end to end. And the CO2 from dry ice is cold - emphacizing its natural tendancy to fill the boat from the bottom up. And, it is 100% CO2, while the candle's exhaust is still mostly nitrogen. So the candle flame creates diluted, hot CO2 that is very likely to evacuate. Dry ice creates cold, pure CO2 that is very likely to stay at home. Do you actually see no danger in this practice? By the way, a lighted candle in a closed container will kill you. What you may be missing is that cold CO2 _will_ collect in a "pool" at the bottom of the boat, gradually filling the boat until sleepers are immersed in it. The weight of the CO2 effectively closes the container. Blase comments about ventilation simply expose our ignorance! I don't know how much CO2 it would take to fill the boat up to the bunks. Nor how fast that amount could be released in different conditions. Nor what the effect of ventilation of different kinds might be. (I do know we often experience dead calm conditions while anchored overnight during the summer.) My point is that conducting the experiment (exactly what I would be doing if I used dry ice in the recommended way) in ignorance is very risky. And the best advice I have is to avoid the practice. David Lady Lillie
Dry ice concentrates a whole lot more CO2 than a candle will produce burning end to end. And the CO2 from dry ice is cold - emphacizing its natural tendancy to fill the boat from the bottom up. And, it is 100% CO2, while the candle's exhaust is still mostly nitrogen. So the candle flame creates diluted, hot CO2 that is very likely to evacuate. Dry ice creates cold, pure CO2 that is very likely to stay at home. Do you actually see no danger in this practice? By the way, a lighted candle in a closed container will kill you. What you may be missing is that cold CO2 _will_ collect in a "pool" at the bottom of the boat, gradually filling the boat until sleepers are immersed in it. The weight of the CO2 effectively closes the container. Blase comments about ventilation simply expose our ignorance! I don't know how much CO2 it would take to fill the boat up to the bunks. Nor how fast that amount could be released in different conditions. Nor what the effect of ventilation of different kinds might be. (I do know we often experience dead calm conditions while anchored overnight during the summer.) My point is that conducting the experiment (exactly what I would be doing if I used dry ice in the recommended way) in ignorance is very risky. And the best advice I have is to avoid the practice. David Lady Lillie
David , All I was suggesting was replacing the
people with the candles. People and candles need oxygen to keep their lights on. CO2 displaces the O2 and the lights go out. Put a mouse and a candle and a lump of dry ice in an aquarium and watch what happens.
people with the candles. People and candles need oxygen to keep their lights on. CO2 displaces the O2 and the lights go out. Put a mouse and a candle and a lump of dry ice in an aquarium and watch what happens.
Ballpark figures
In the average cooler, the average block of dry ice sublimates at a rate of 5-10 lb/day (slower if you keep it closed and seal it up). 1 lb of dry ice contains roughly 235 L of CO2 at standard temperature and pressure, which is enough to "poison" 4700 L of air (shooting for 5% CO2, remember the movie Apollo 13?). www.dryiceinfo.com For comparison, the average adult human exhales 216 L of CO2 per day. Of course, you would still need to factor in the fact that exhaled human breath is 94-98F, and sublimated CO2 is -109F, factors which will affect distribution within poorly-stirred air.
In the average cooler, the average block of dry ice sublimates at a rate of 5-10 lb/day (slower if you keep it closed and seal it up). 1 lb of dry ice contains roughly 235 L of CO2 at standard temperature and pressure, which is enough to "poison" 4700 L of air (shooting for 5% CO2, remember the movie Apollo 13?). www.dryiceinfo.com For comparison, the average adult human exhales 216 L of CO2 per day. Of course, you would still need to factor in the fact that exhaled human breath is 94-98F, and sublimated CO2 is -109F, factors which will affect distribution within poorly-stirred air.
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