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Free flow at 94' ffw

Discussion in 'Near Misses & Lessons Learned' started by 0321tony, Jun 20, 2019.

  1. 0321tony

    0321tony Registered

    I started with a full 100 at just under 3000psi I finally downloaded my dive profile to look at exact times and rate of ascent and it took me four minutes to get to the surface from where I turned the dive at 94ffw it looks like I stopped my descent for about 20 seconds at that 94ft before going up so I am assuming that I spent that 20 seconds problem solving. My free flow started off slow and I'm not sure how long it took to reach full free flow but my guess was probably only 10 to 15 seconds my stop was a minute 38 I had been down only 7 minutes when I made the ascent so I had not used much air from the tank so it took about 4 and a half to 5 minutes for that tank to go from about 2700psi to 300psi obviously an 80 would go much faster so it depends on the tank you dive.
    I remembered coming across this chart a few months back and found it interesting so I hunted it back up. I think this is for an 80 at 3000psi my time was a bit longer so obviously its not exact but it wasn't too far off from my experience.

    stepfen likes this.
  2. 2airishuman

    2airishuman Contributor

    # of Dives: 100 - 199
    Location: Greater Minnesota
    Based on the description, I believe it was likely that it was the 1st stage that was freeflowing. It was just venting through the alternate.

    Freeflows in cold water are not unusual and no reg is completely immune. Good on you for bringing a pony

    LP shutoffs are IMO not a good thing. The way to resolve this problem at depth without ascending is to switch to a pony (or the other post, if diving twins) and shut the tank valve for the offending reg. If the freeflow is caused by ice, the offending reg will usually thaw out after a few minutes, and then you can switch back.
    Pweintz likes this.
  3. Magnus Lundstedt

    Magnus Lundstedt Instructor, Scuba

    # of Dives: 200 - 499
    Location: Umeå, sweden
    If you have 1 first and 2 second stages. Closing the lp to the free flowing 2nd would, if the problem is the 1st stage, result in the other 2nd stage free flowing rather than a blown hose.
  4. Gareth J

    Gareth J Contributor

    # of Dives: 1,000 - 2,499
    Location: UK
    Yes - I'm too used to twinset and single regulators. However you look at it, it will probably make things worse, two 2nd stages free flowing rather than one.
  5. Magnus Lundstedt

    Magnus Lundstedt Instructor, Scuba

    # of Dives: 200 - 499
    Location: Umeå, sweden
    No, not realy.

    if you close the ome that i free flowing you get one off two results.

    1. it was the 2nd that faulted, you stop the flow.
    2. if it is first stage creep, you close one, the other one starts to flow, you open the flowing one again and you are back where you started.

    But what do I know, if my first starts to flow, the opv dump it out and i can use it as usual till the air runs out.
    Sam Miller III likes this.
  6. Frosty

    Frosty Instructor, Scuba

    # of Dives: 500 - 999
    Location: Auckland NZ
    I'm curious NOT critiquing . Why wasn't breathing that freeflow reg for awhile an option ?
    chillyinCanada and rsingler like this.
  7. 0321tony

    0321tony Registered

    The freeflow was coming from my alternate. I was able to keep breathing from my primary like normal.
  8. BlueTrin

    BlueTrin ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 100 - 199
    Location: London
    I think he meant to say that you may save air by breathing the freeflow reg.

    IMHO it is not obvious to me that it will lead you to get more air time with the additional focus on breathing the freeflow reg.
    williamlee likes this.
  9. cerich

    cerich ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 5,000 - ∞
    Location: Georgia
    ummm.. a first stage freeze will make whichever second stage that has a lower cracking pressure freeflow. Frankly when I dive in water that cold I set my IP lower to around 120 as well. The predive and detuned will have zero bearing on freezing or not (1st or 2nd stage) so not sure where you got that idea.

    Thinking it was your drysuit first,.. is a bit weird to me, it would have been my last thought as if it went I would immediately feel my buoyancy change. Please don't take this wrong, that you felt it could be and you didn't notice any change in buoyancy.. any chance you dive quite overweighted? By the way, going vertyicle should never be part of the solve a problem process IMHO
    beester likes this.
  10. 0321tony

    0321tony Registered

    As far as detune and predive in my alternate I do that so to help it keep from being too sensitive but only on my alternate, if I am not understanding what you are trying to say here, my apologies. I am not a reg tech and don't set my own IP's however I have thought about getting the tools and training in the future.
    My weight is good, I dive a couple pounds over weight 2-3 but for me I like it because I don't like to be on the raged edge of weighting when I am in bulky undergarments but that's me. I was in black water so I had zero visual reference to my surroundings and really never would have expected my alternate to be the one that went into freeflow so when I felt air coming from around my neck my first thought was that it was air coming out of my neck seal. The reason I went vertical was that if it was my drysuit inflater malfunctioning it would continue to leave my neck seal and not fill my feet up with air and I end up breaching the surface like a backwards whale from 100'. As far as feeling a change in buoyancy I suppose its possible but with a full on freeflow blasting me in the face it was a bit disorienting and I was doing my best at problem solving and trying to calmly but quickly eliminate the possible issues at hand.
    BlueTrin likes this.

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