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Looking to Buy a Rebreather

Discussion in 'Rebreather Diving' started by SentinelAce, Jul 5, 2021.

  1. andrespp

    andrespp Registered

    # of Dives: 5,000 - ∞
    Location: Spain
    28
    5
    The only reason that I can think of for diving a CCR with a normoxic gas is during air breaks on very long decos. And anyway, the diver doing so should be very on top of his/her ppO2, even more considering that it is a mCCR.
     
  2. stuartv

    stuartv Seeking the Light ScubaBoard Supporter

    # of Dives: 500 - 999
    Location: Lexington, SC
    9,907
    5,765
    What percentage of CCR divers do you reckon are actually trained to be able to use a hypoxic dil (as I presume you are suggesting)?
     
  3. andrespp

    andrespp Registered

    # of Dives: 5,000 - ∞
    Location: Spain
    28
    5
    The assumption you are making is wrong....a normoxic mix can be obtained in the loop using non hypoxic dil. Second, I do not see how your question is related to the discussion.
     
  4. tbone1004

    tbone1004 Technical Instructor ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Greenville, South Carolina, United States
    18,776
    11,284
    I don't know many people that use the CCR for air breaks because of the nuisance of stabilizing the whole loop back. They will either kick over to an OC regulator or they will let the ppO2 decay down naturally as your body is offgasing and then O2 flush it back up.
     
  5. stuartv

    stuartv Seeking the Light ScubaBoard Supporter

    # of Dives: 500 - 999
    Location: Lexington, SC
    9,907
    5,765
    You said this:

    "Normoxic gas" is anything with 16% - 21% O2, right?

    So, the only way I am able to interpret your statement is "the only reason for diving a CCR with a dil that has 16% - 21% O2 is ...".

    On further thought, I think you are talking about the inspired ppO2 and making the distinction that the diver should be breathing a hyperoxic mix (i.e. a mix with a ppO2 greater than 0.21). Correct?

    My impression was that nadwidny was not making that distinction. He was simply saying that the loop can go from non-hypoxic to hypoxic quickly.
     
    nadwidny and rjack321 like this.
  6. nadwidny

    nadwidny Instructor, Scuba

    # of Dives: I just don't log dives
    Location: Cranbrook, BC
    1,921
    555
    Yup. In a perfect world that would work. Until it doesn't. As I found out.
     
  7. andrespp

    andrespp Registered

    # of Dives: 5,000 - ∞
    Location: Spain
    28
    5
    That´s it.
     
  8. andrespp

    andrespp Registered

    # of Dives: 5,000 - ∞
    Location: Spain
    28
    5
    I do not know what kind of ccr you use, but with a mccr you need to both monitor frequently your ppO2 especially when close to surface and have a mix rich in oxygen on the shallows. If the pasive orifice clogs and you fail to monitor your ppo2 for such amount of time, is an human error on top of a mechanical issue.
     
  9. andrespp

    andrespp Registered

    # of Dives: 5,000 - ∞
    Location: Spain
    28
    5
    Nuisance? Flushing the loop out once or maybe twice is a nuisance? Really?
     
  10. Wibble

    Wibble Contributor

    # of Dives: 500 - 999
    Location: UK
    1,251
    963
    Seems an excellent idea.
    Any chance of a photo?
     

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