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Very near miss - panic and hyperventilation at 70 feet

Discussion in 'Near Misses and Lessons Learned' started by jsnorman, Sep 16, 2015.

  1. Adobo

    Adobo DIR Practitioner

    # of Dives: 100 - 199
    Location: Northern Cali
    1,580
    318
    83
    If we want people to continue to share their "near misses" for everyone's benefit, we should make an effort to make sure our comments and questions are constructive in nature.

    Anyone considering sharing their "incident" might find this kind of judgmental commentary to be a real disincentive.
     
  2. jsnorman

    jsnorman Solo Diver

    # of Dives: 200 - 499
    Location: Chicago, IL
    27
    17
    3
    I did calculate for the heavier and larger steel 120s, but ...

    I know it seems rather idiotic, but I got the fresh vs salt water bouyancy issue backwards. Remember I **never** set fins in fresh water (except the pool during classes), and when I took my last chemistry and physics classes Ronald Reagan was still President (and I didn't do very well at all in Chemistry, maybe not surprising to you).

    I was absolutely relying (too much) on my buddy to help me figure out the weights for fresh water, so I did not do any really detailed buoyancy calculation beforehand. I did look up the additional negative buoyancy for the 120s vs the AL80 (difference of 9-10lbs), and got an estimate from the dive shop where I bought of extra weight for the 7mm suit, thick boots, gloves and hoodie (+15lbs). With that info, I thought my buddy would be able to help me figure out the proper base weight to try. After we were underway though, my buddy had no idea what adjustment I needed to make for weights. When it was clear that he was not going to be much help with figuring out my weights, I did some very quick math but I got one very important fact wrong - for some reason (maybe task overloading) I calculated as if fresh water was more dense/heavier than saltwater. I am sure I knew that wasn't right, and if I had thought about it before getting on the boat I would not have made that mistake (I sure know it now!), but rushing through dive prep and dealing with the inflator hose issue, moving regs, etc. I got the adjustment backwards.

    I don't recall how I ended up with the exact number I did, but FWIW the calculation was something like:
    Base saltwater: 12-15lbs
    +15 lbs for wetsuit, gloves etc.
    -9 lbs for heavier steel 120s vs my usual AL80s (difference in bouyancy with full tank)
    = 18-21lbs (saltwater with adjustment for 7mm suit, gloves, hood, and 120s)

    Then I added 25% to convert to freshwater (should have subtracted) which is how I ended up so overweighted.

    Strangely I ran over the calculation with my buddy and he thought it seemed right. As I said before, the one thing I really was disappointed in my buddy for was his failure to work on proper weighting with me; either he didn't know how to estimate the weights, or he wasn't paying much attention. I don't blame him for the whole thing, but as someone said earlier his fresh water experience was the reason I was paying for the boat charter so I do think he failed me at least in that respect badly.

    ---------- Post added September 18th, 2015 at 02:01 PM ----------

    FWIW, I take chilly's point and I think his comments have been constructive. I took a few too many risks on the dive, and made a couple of dumb mistakes. That is why I waited so long to even write about it, I was pretty embarrassed by the whole thing.

    One thing I hope everyone understands is how easy it is for this to happen even (maybe especially) for an experienced and well-trained diver. There was a series of small and easily overlooked/dismissed errors in judgment or mistakes. It was the cumulative effect of several of these errors and mistakes that led to the mess. The reason I wrote this at all is that I hope other divers (and especially experienced divers) don't assume they are immune from making similar errors in judgment, on the assumption that its not a big deal and something that can be easily handled. It is very easy to do especially with experience. If all that people get from my experience is that I was an unsafe diver (or that my buddy was a bad choice) then I failed to convey the most important lesson learned, which is that small things can matter a lot and you have to pay attention to the cumulative effect of small added risks/changes/etc.
     
  3. chadmeister

    chadmeister Nassau Grouper

    # of Dives: 0 - 24
    Location: Dubai
    157
    16
    18
    That's something that gets me thinking a lot since in my everyday life I try to always 'not forget' the essentials in doing something I would else find simple.

    Good point.
     
  4. bryanmc57

    bryanmc57 DIR Practitioner

    # of Dives: 500 - 999
    Location: Mineola, TX
    289
    60
    28
    I consider us (divers) to be somewhat like family. That said, when someone comes in with a story similar to the OP, they pretty much have to expect a few posts that will read like "You did what???" It's how we learn.... and grow.
     
  5. Russoft

    Russoft Barracuda

    # of Dives: 50 - 99
    Location: Minneapolis
    232
    110
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    I suppose body size does factor in quite a bit in calculating proper weight, as does age of your wetsuit, but with a 2-pc 7mm, gloves, hood, booties and AL80, I am STILL overweighted when I wear only 20 lb with 500 psi in the tank.
     
  6. archer1960

    archer1960 Manta Ray

    # of Dives: 50 - 99
    Location: Southern New England, USA
    572
    135
    43
    Another big error: it should be 2.5%, not 25%, and it is applied to your *total* weight. So if you plus your kit total 250lb, then you remove 250 * .025 = ~6lb.
     
  7. chadmeister

    chadmeister Nassau Grouper

    # of Dives: 0 - 24
    Location: Dubai
    157
    16
    18
    Hi guys! So I wanted to let you all know that this post helped me out a lot today. I remained calm during my last 2 AOW dives and all went well with me, but how did this post work out for me? Well, first off when my partner suggested I take the GoPro and snap pics while down there I declined because I was in full new gear (save the fins and the mask/snorkel) so I didn't want any more stress. Also, I had insisted to do a safety check with my instabuddy but he wanted to pee so he jumped in, turns out his 2nd tank had a problem and half way through he had to hold on to the instructor... Ah well, all ended well but I still checked my own stuff :) I know that's not ideal... But I had to do it I guess :)

    Anyway, point is I did what was said here and I dived my comfort zone and I thank you for sharing!!
     
  8. John C. Ratliff

    John C. Ratliff Instructor, Scuba

    # of Dives: I'm a Fish!
    Location: Beaverton, Oregon
    2,821
    1,385
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    First, it was not the "7 mm suit," but the ill-fitting 7 mm suit. We don't have custom wet suits anymore, and the sizes that are used don't fit everyone. A dry suit has it's own problems, including neck constriction for the neck seal. Suit manufacturers have decided not to do custom wet suits anymore, although a few are still around. Wet suits are usually a better bet for ease of diving, as they don't require an extra inflator. However, when you say it was a "semi-dry wet suit," with neck and wrist seals, the neck seal could be a big problem. We I got my last wet suit, I needed to cut back the neck portion so that it would not constrict me.

    Second, you were not doing a buddy dive. You were "buddies" in name only, and your "buddy" was a "same lake buddy." He was not there to help. I have seen fatalities recently due to loss of buddy contact, to the point that on one fatality I asked whether it's time to bring back the buddy line. A short buddy line will keep you in positive contact, but enforces a discipline that one needs to train to.

    In 1973 I took my NAUI Instructor Training Course (ITC), and while there we were taught about a problem that I have not heard mentioned much recently, the Hyperpnea-Exhaustion Syndrome. I looked in my NAUI materials, and it's not readily accessible, but I did find this publication by Lee Somers from the University of Michigan years ago:
    This publication probably dates back to about 1986, possibly before. Lee Somers was well known in the 1970s and 1980s for his contributions to diving science. I think, if you'll think through this, that your regulator was fine, but your breathing was not, and that you were suffering from hyperpnea-exhaustion syndrome. When this happens, according to my early NAUI training, you tend to focus very narrowly upon things, and for you that was climbing the anchor. In many situations, the diver in this state tries to "climb out of the water's surface." You, however, had the anchor line to hold onto. You also focused on keeping, or reacquiring and keeping, your regulator in your mouth while in the chop on the surface.

    Being highly overweighted exasperated the situation. My calculations are a bit differently calculated than some others. The weight of a cubic foot of fresh water is 62.4 pounds, while the weight of a cubic foot of salt water is 64 pounds. If you divide 62.4 by 64, you get 0.97. If you then multiply it times the amount of weight you calculated, 18 pounds, that you need, you get 17.55 pounds. Or, take about a half pound off the weights. Instead, you added about five pounds to your weights.

    I have done a lot of accident analysis in my days as a safety and health professional. You are very correct in thinking that a number of small errors can lead to a much larger disaster, such as the incident you describe. The way around this is to take care of these details in the days and weeks prior to the event, not an the day of the event. There were way too many details that you needed to attend to, correct, and get right while already on the boat. These should have been taken care of prior to the day of the dive. Examples:

    --Take the wetsuit into the pool with all the equipment, and figure out the weighting you needed.
    --Assemble the gear prior to the day of the dive, and make sure everything worked correctly.
    --Talk with your dive buddy, and get very specific about your needs and expectations. Maintaining buddy contact means staying very close to the buddy, say 10 feet maximum. It does not mean, "I'll see you on the bottom sometime."
    --Set emergency procedures if buddy contact is lost.
    --Don't dive unless your equipment is functioning correctly, or you ascertain it is not a safety critical item for that dive.

    Concerning your decision to dive, I have had a saying that if the question of whether to dive or not enters my mind, the decision is to not dive. The reason is another near miss I have not written about, which my buddy and I "evaluated" surf conditions for over half an hour before deciding to dive, when out on a rough day, got rolled by a breaker, and spent three and a half hours awaiting a pickup by the U.S. Coast Guard. It happened, because we did everything right except decide to dive. So if the thought comes into you mind about whether or not to dive, DON'T DIVE. Everything after that is a rationalization.

    Finally, let's talk about dropping weights. When we were using weight belts (I still do), we could take them off and hold them in our hands. That way, if we blacked out, we would automatically drop them. If we succeeded in reaching the surface, we could put them back on. Modern weighting systems make that more difficult, but should not influence the decision to drop weights. Without a functioning BC (not counting oral inflation), dropping weights become the only means of attaining the surface in this situation. But remember, you would not be dropping all your weights, as you had that 9 pound heavy steel tank on your back. You could have dropped your weights, then "flown" over to the anchor line and used it to keep you from an uncontrolled buoyant ascent.

    A similar situation happened concerning the divers off the Coast Guard Cutter Healy, whereby two divers drowned when overweighted and not having their BC hooked up to a power inflator, as they had only one and used it on their dry suits. They also used full-face masks, so oral inflation was not possible. There were many other events which played into this fatality, but it has some similarities to this situation.

    One final thought, not mentioned by the others. When I was a USAF Pararescueman, I took a long flight with SMSgt. Jerome C. Gorney, who had been in Pararescue for many years. He told me, "John, attention to detail. You get the details right, and the jump (dive) will go off well. You don't get the details right, and all sorts of **** can happen." (Or, something to that effect.) You get the drift. These dives are rather complex undertakings, and you need to pay attention to the details, in the planning stage as well as in the execution stage. It is in the planning stage that we set ourselves up for success, or an incident/accident.

    SeaRat
    NAUI #2710 (inactive)
     
    Last edited: Oct 12, 2015
  9. Freewillow

    Freewillow Divemaster

    # of Dives: 500 - 999
    Location: Brussels
    1,664
    417
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    Dear Opp,


    thank you for sharing.

    Indeed, quite a few mistakes that could have lead to your death. The firt one was to change regulator because you could not connect the medium pressure hose. If you have been trained properly, you should have practiced the detachment of the MP house and oral inflation. From that you sould have known that your MP house disconnected was perfectly safe. It is also a skill that can turn VERY usefull in the case that your BCD inflator get stuck opened. For the disconnected MP Hose, let me tell you that I am diving with two MP hoses: one for my BCD ( connected ) and one, not connected, for the inflation of my closed - and large 20 kg - Halcyon SMB.


    I think that what separates a experienced diver from a proficient experienced diver is continuous training. I have been diving for 25 years and roughly 750 times. But the last course that I have taken was 2 years ago. A good way to maintain and refine diving skills.
     
  10. denisdiving

    denisdiving Garibaldi

    # of Dives: 0 - 24
    Location: montreal, quebec,canada
    1
    0
    1
    glad your share your stories, I'm new in diving world. I was in Cuba, Playa Costa Verde last week. I dive with a group who was more experience than me, after tell two or three time to my tourist dive master, I will missing so air. He didn't care that much, I have to go up, and I want to fast to get to surface. I did some hyperventilation, I know now all about the health problem after. I feel much better now. Now, I have to take care of myself than dive master who don't care about safety... but more than show the fish around us.

    ---------- Post added November 12th, 2015 at 09:56 PM ----------

    glad your share your stories, I'm new in diving world. I was in Cuba, Playa Costa Verde last week. I dive with a group who was more experience than me, after tell two or three time to my tourist dive master, I will missing so air. He didn't care that much, I have to go up, and I want to fast to get to surface. I did some hyperventilation, I know now all about the health problem after. I feel much better now. Now, I have to take care of myself than dive master who don't care about safety... but more than show the fish around us.
     

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