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3 Reg Failures

Discussion in 'Near Misses and Lessons Learned' started by Vicko, Sep 13, 2019.

  1. Vicko

    Vicko Barracuda

    # of Dives: 50 - 99
    Location: Komizža, Croatia
    322
    234
    43
    While diving solo on a wreck of the B-17 I had a interesting experience. The wreck is 50 meters of shore in 70 meters of water. I was diving sidemount with 2 bottom gas tanks and 2 deco gases. First a group of 8 divers jumped in, after passing all the stages to them in the water I kitted up, made sure all regulators were working again, as well as no bubbling, closed the deco cylinders and went down.
    20 minutes of bottom time later (terrible dive, 5 meter visibility) I was the last person on the wreck. Usually people swim the 50 meters to a wall on the bottom and then ascend to deco but I prefered to ascend on the rope and swim the distance after the switch to 50%. At this point I had around 100 bars of gas in both primary tanks.
    The ascent went without problems to 50 meters after which my left first stage started free flowing a lot. I switched to the other one, closed the tank aaaand... got a big mouthful of water, the second stage on the other regulator started leaking water and free flowing. After weighing my options I stated breathing from the left one again while feathering the valve. I also increased my ascent rate to about 20 meters a minute and skipped half of the deco stops from 30 to 21 meter. I had to switch regulators on the way and breathed a bit from the leaky one. At this point I had around 30 bars in both primary tanks and around 25 minutes of deco with 50% and O2.
    Upon reaching my 21 meter stop (and thinking finally) I took 2 breaths from the 50% reg upon which it also started to freeflow with no gas reaching the second stage.
    After flipping Poseidon the bird (the greek god, not the regulator) I considered switching the O2 reg onto the 50% but decided that potentially having no working regulators was a lot scarier than breathing o2 too deep once I was out of bottom gass.
    I decided to swim the distance to shore while decoing on the faulty regulators considering that in the worst case scenario I could take some deco gas from the divers decoing there. I must say that whatever people say about sidemount at least it makes the valves easier to operate.
    After reaching 9 meters my left tank was just about empty, my right one was at 10 bars. Luckily I already tried to breath pure O2 at 12 meters ( in a safe monitored environment, don't get mad) so I was confident that after everything else went wrong at least I would not do the high ppo2 dance. My dive lasted 61 minutes with additional 10 minutes of o2 at 6ish meters instead of the planed 45.

    As you can read I did not survive.

    Upon closer inspection on the surface the bottom left regulator works fine, obviously it will be disassembled and rebuilt. the right second stage sprays a fine mist of water over my mouth when I breath it wet but stopped freeflowing, will also get rebuilt.
    The 50% reg did not have a oring in it, which raises 2 questions. Either the oring somehow got extruded during the dive and went shooting out (is that even possible on a DIN reg?) or it managed to seal on the surface for over 3 hours and then stopped after 20 minutes of the dive without a oring (just how?) All regulators were serviced by a very capable technician less then 3 months ago and had 50 or so dives on them in the meantime.

    Some days ago I commented that the chance of a regulator failure in the Adriatic is so low I don't even consider it. Considering such a low chance after 3 regulators failed on me statistically I can dive a single first stage for the rest of my life.
     
  2. lermontov

    lermontov Manta Ray

    # of Dives: 500 - 999
    Location: christchurch
    795
    354
    63
    makes me wonder if the previous dive had had an effect on the regs -did you use all same regs on the previous dive was it silty dirty etc? did you clean them etc what was a water temp.
     
  3. lexvil

    lexvil Loggerhead Turtle

    # of Dives: 1,000 - 2,499
    Location: jamestown, ca.
    1,771
    1,283
    113
    Sorry you didn’t survive, I think Poseidon May have had in in for you. What regulators were these? Who does the service?
     
    couv likes this.
  4. Vicko

    Vicko Barracuda

    # of Dives: 50 - 99
    Location: Komizža, Croatia
    322
    234
    43
    Regs were scubapro and apeks, in decent shape. No silt or dirt at all, soaked in fresh water while pressurized after every dive.
    Water temperature was 16 Celsius when they failed.
     
  5. lexvil

    lexvil Loggerhead Turtle

    # of Dives: 1,000 - 2,499
    Location: jamestown, ca.
    1,771
    1,283
    113
    Diaphragm or piston on the scubapro? Have they been torn down since? Any chance there was a slug of water in the tanks?
     
  6. Pao

    Pao Manta Ray

    # of Dives: 200 - 499
    Location: Manila, Philippines
    995
    210
    43
    Wet gas and frozen regs? The missing o-ring is harder to explain. Have you made any enemies lately? :D
     
  7. JackD342

    JackD342 Dive Shop

    # of Dives: 500 - 999
    Location: Highland Park, IL
    2,373
    1,394
    113
    Last things first - the DIN reg with the missing o-ring: I don't see how the o-ring could have been blown out in the water on the dive. While highly unlikely, it is possible that you did have a metal to metal seal without the o-ring at the beginning of your dive. I suppose you could remove the o-ring and experiment if you like, but you may never know. (Of course if you that missing o-ring loose in the bottom of a bag, that could be a clue...)

    If you don't find any faults during your service check (or added overhaul) then the other fails are even harder to figure. Regarding the 2nd stage that was breathing wet, the only "reasonable" explanation I can think of is a problem with the exhaust valve or the diaphragm. Assuming the case isn't cracked. Beyond that one has to try and figure out how water may have found it's way into the system. Your tanks, or rentals? Possibly water in the cylinder from the start? Alternatively, after you assemble and test your sets and then turn off the air, is it normal to bleed the pressure or do you leave them pressurized but off? (I only dive single tanks myself.) If there is no pressure in the system, could you have allowed some water into the system through the 2nd stage on the dive?

    And then there is the free flow mystery. At the temperature you cited I would not expect ANY regulator to freeze up, even if not rated for cold water. But I suppose if yours are all rated for >10°C and enough other contributing factors exist, it still might be enough for it to happen. (denser air at depth, rapid breathing, water inside 1st and/or 2nd stage...)

    Let us know what you find after the service, I'm sure many are curious. Also, if you provide some specifics on which brands/models exhibited which behavior, you might get some better feedback.
     
  8. couv

    couv Instructor, Scuba

    # of Dives: 1,000 - 2,499
    Location: 13th floor of the Ivory Tower
    4,829
    2,113
    113
    Could you rephrase that? Do you mean the left second stage was freeflowing or the left first stage was leaking gas?

    Cheers,

    Couv
     

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