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Nitrox course. What's the point?

Discussion in 'New Divers and Those Considering Diving' started by Dody, Jan 9, 2021.

  1. JimBlay

    JimBlay Divin' Papaw ScubaBoard Supporter

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    Yes and No. No in that what matters most is your NDL and your ascent practices. Yes in that if you do the same dive on Nitrox vs Air your nitrogen loading will be less and thus, at least in theory, the dive will be safer. This is magnified if doing multiple dives. With that said that is really a hypothetical situation because rarely are you doing the exact same dive if using Nitrox. You are staying longer and may be coming just as close or closer even to your NDL than if you'd used air. In that instance the Nitrox dive may be "less safe" than the Air dive.

    The primary reason for using recreational Nitrox is to increase your NDL. That is seen most clearly on repetitive dives in the 40-100' range using something like EAN36.

    But with the hypothetical situation aside I tend to agree with you. The whole theory of NDL supports your view. Dive within them and pay attention to your ascent practices and the gas you are using is irrelevant to the level of safety of the dive.
     
  2. mac64

    mac64 ScubaBoard Supporter ScubaBoard Supporter

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    Stop moving the goalposts. I said nitrox is not safer than air if both are dived to NDL, the nitrogen loading is the same.
     
    DiveClimbRide and scubadada like this.
  3. JimBlay

    JimBlay Divin' Papaw ScubaBoard Supporter

    # of Dives: 500 - 999
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    Not moving any posts. Just adding discussion. Sorry if that upsets you but this is ScubaBoard. That's what we do here. It is possible for Nitrox to be safer than Air even within NDL if by "safer" we mean less nitrogen loading.
     
    peocro likes this.
  4. Gareth J

    Gareth J Manta Ray

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    See Page 17

     
    JimBlay likes this.
  5. tursiops

    tursiops Marine Scientist and Master Instructor ScubaBoard Supporter

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    See page 17, or post #176, which has important information in it:
     
    chillyinCanada and JimBlay like this.
  6. MichaelMc

    MichaelMc Working toward Cenotes ScubaBoard Supporter

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    Well..., If you dive each to NDL then do a standard ascent and safety stop, the nitrox will do more off-gassing than the air will. So safer when you surface.

    But my diving is limited by N2 loading, gas, cold tolerance and desire for lunch. Nitrox brings the later three to the front as what brings me up, meaning I have less N2 loading, always a good thing.
     
    Searcaigh, arthurng311 and JimBlay like this.
  7. mac64

    mac64 ScubaBoard Supporter ScubaBoard Supporter

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    That’s my point, the nitrogen loading is the same if there both dived to their respective NDL and for rec diving nitrox has the added risk of a higher PO2 than air
     
  8. JimBlay

    JimBlay Divin' Papaw ScubaBoard Supporter

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    The added ‘risk’ is minimal if the PPO2 is kept within guidelines and the ‘risk’ is offset by real benefits.
     
  9. JimBlay

    JimBlay Divin' Papaw ScubaBoard Supporter

    # of Dives: 500 - 999
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    Also as has been pointed out on this thread the nitrogen loading is not identical between the two gases even if both are used within NDL.
     
  10. mac64

    mac64 ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 5,000 - ∞
    Location: Ireland
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    If you stay at depth for the max allowable time for nitrox or air the nitrogen loading is exactly the same. Why do you think you get longer bottom times on nitrox?
     

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