Gas expansion limit?

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Kevin Floyd

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Is there a limit to how much breathing gas will expand under earth normal conditions?

if I fill a lift bag half full at 33 ffw, it should be full when it reaches the surface. If I pull it back down and dump half it’s air will it again be full at the surface?
 
? Maybe not understanding your question.

If you pull it back down, the volume will be halved and it will be half full again. You'll just be back where you started.
 
If you pull it back, the volume will be halved. You don’t need to dump it.
 
Is there a limit to how much breathing gas will expand under earth normal conditions?

if I fill a lift bag half full at 33 ffw, it should be full when it reaches the surface. If I pull it back down and dump half it’s air will it again be full at the surface?
Like jgttrey, I don't really understand your question. The response from jgttrey is correct, but I will try a different response to the last part of your question. If you pull it back down, then it will have compressed to its original size--half full. If you dump half of it, then it will be a quarter full. If you send it back to the surface, it will be half full.
 
? Maybe not understanding your question.

If you pull it back down, the volume will be halved and it will be half full again. You'll just be back where you

now that I ask it out loud I realized it’s a stupid question
 
now that I ask it out loud I realized it’s a stupid question

Not a stupid question, you just need to think about it more. If you inflate a balloon say with He and let it go, it will continue to expand until it reaches the limits of the balloon material. If you had a magical balloon that could expand forever, I don’t know if the He would reach a limit of being about to generate a pressure gradient. That is a question for better brains on SB. I will now enjoy my third cup of coffee. Be safe
 
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