a silly question ...?

[Lew Morris]

If one is using dry ice as a refrigerant in one's 40 foot sailboat (and "one" is) ... what happens to the off-gased carbon dioxide?

Obviously the volume of DI being used would be a factor, but let's assume that the amount involved would fill two large coolers.

Is it a threat to the crew?

Should a CO2 monitor be installed?

Thanks.

[Sandrak]

That is not a silly question at all. I am planning a weeking trip in my 35footer this weekend and was planning on using dry ice also. I haven't thought about carbon dioxide poisoning. I am now wondering if it is safe. I have 3 children to worry about. One being 2 years old.

[SailDesign]

There is a reason why you can't buy dry ice in West Marine......
Any off-gassed CO2 will collect in the bilge, and the level will rise as long as there is any DI left. At some point it WILL achieve the level of a bunk, and the price of a real cooling system will seem as nothing by comparison.

Steve "harbinger of doom for the day, but I hope you see my point....."

[Robert Miller]

I have used dry ice for years when cruising, and I've never worried about it. Maybe I should have. I don't know. I AM NOT AN EXPERT ON THIS.

To relate only my experiences, though, ... ... In all cases, I've used top loading iceboxes. When you lift the lid off, the CO2 tends to stay pretty much where it is... I've noticed some, but limited expression of the gas into the air around me, except when I get my head too far down in the ice-box while searching for something. The CO2 gas is certainly cooler than the ambient air in the cabin, and so has no real tendency to come floating up and out of the icebox. I would not use dry ice in a less contained situation, such as a front opening fridge.

The biggest problems I've experienced are foods freezing, that were placed too close to the dry ice in the cooler, and were ruined (produce, for eg.).

As for CO2 gas that does escape into the cabin, the volume will be pretty small compared with the total volume of air in the cabin. Add to that any ventilation you have flowing in the cabin, and I again feel that It's not too big a risk.

Are you guys sure you're not worrying about carbon monoxide? Unlike CO2, CO is a terribly big risk, even in tiniest concentrations! So I do have a CO monitor ... the expensive kind with numbers on an LCD display in PPM. Buy one of those and use it! And then worry anyway. We NEVER run the engine to charge batteries at the mooring with anyone sleeping below. Never. Look also to your cook stove and cabin heater. Again, worry, always, about carbon monoxide.

But getting back to carbon dioxide, CO2, a further disclaimer: I say again I am not an expert on the matter. Only that I, myself, have not been too worried about using dry ice, as I've described.

If someone has better (more scientific) information to offer, I'd love to read it. I cruise with my kids too.

Robert

[Lew Morris]

Thanks Gentlemen,

My partner and I have ben debating this issue for awhile now.

It was our intention to use the DI only for long term storage; i.e. not for frequent or ready use items (beverages, condiments, etc). We figured that two custom built insulated boxes adjacent to our water tanks (under the settee) on either side would be a workable location.

And then we realized that that gas had to go somewhere...

Plenty of cross-ventilation ought to do the trick, but a CO2 alarm would certainly increase that warm fuzzy feeling one gets right before nodding off for the night.

More comments would be appreciated... by all of us, I'm sure.

[yipster]

dry ice CO2 for rocketry http://www.h2orocket.com/topic/dryice/dryice.html
Nasa’s virtual bottle launch platform: http://www.grc.nasa.gov/WWW/K-12/bot...ket/br2d_b.swf
have fun but be aware and carefull, http://science.howstuffworks.com/question264.htm silly dry ice uh