Overconfidence Always Leads to Trouble

Monday, May 16, 2011 18:06 | Filled in Dive Safety, Dive Training

Aqutic Safaris II from below

Back from Another Safe Dive

I know you have heard this before.  Don’t be overconfident.  You will get bit in the rear one of these days.  Overconfidence leads to intentional lapses on quality control standards and unintentional lapses with safety guidelines.  In the world of diving, avoiding overconfidence is critical to having fun and being safe.

 

I was headed out to the Fossil Ledge on a dive in early spring.  The water was still pretty cold so I ended up buying a 5 mil neoprene hood from the dive shop.  This hood/torso piece would help keep me warm enough in the chillier waters.  The other new piece of equipment that I was carrying out with me that day was a 19 cubic foot pony bottle and regulator that my wife got me for a Christmas present.  The day started out nice, and the boat ride out to the location was uneventful.

 

Helmetcam 2.0

Helmetcam 2.0

I geared up for the dive, putting on my equipment which included: 1 wreck reel, my ‘goody bag’, my pony bottle with its quick-draw attachment to my main tank, my canister divelight, and my helmetcam v2.0.  I considered myself an experienced diver and did not feel that I had any issues or concerns gearing up.  I had no problems with the descent to the bottom along the anchor line which lay around 95 feet in depth.  I tied off my wreck reel, put a little air in my BCD and started going out in a relatively random direction.  If you have not done a dive to the Fossil Ledge before, let me explain that 90% of your time is spent on the bottom looking through the sand for teeth and other fossils.  Neutral buoyancy is not much of a concern.  Also, as I swim around, I tend to have a habit of looking at my dive computer on my left wrist to check my air and dive time.  I am slowly going over the sand and between the channels in the ledge looking for anything of interest sticking out of the sand.

 

After around 15 minutes, I see a piece of a whale vertebrae sticking out of the sand.  Now, this was a pretty big piece and it took me a little effort to dig the rest of it out of the sand.  Once it was free, I somehow stuffed it in my bag and continued my dive.  I was now swimming with this heavy bag in my left hand bouncing off the bottom occasionally as I continued to look around.  I look at my dive computer and I believe it says that I have approximately 13 minutes of time remaining in my dive.  About 5 minutes later, I spot a large lobster sitting under the ledge.  I am able to grab it without too much of a struggle.  In fact, there was no struggle.  I believe the water was too cold for it to do much.  I take the lobster in my left hand which is also holding my bag with the large vertebrae.  I press the lobster against my hip/thigh to keep him from struggling and start to reel in my line towards the anchor.

 

Shortly, I notice that it is a little harder than normal to draw on my regulator.  I wonder if it is because of all the sand and silt that I stirred up while looking for fossils.  My next draw of air is also met with resistance.  I take one more draw from my regulator and decide that there is a problem with my system’s ability to provide a good air supply.  I spit out the regulator and put the backup regulator in my mouth from my pony bottle which is attached around my neck.  I know that I have 19 cubic feet of good air and immediately start to abort my dive.  I reel in my wreck reel, clip it off and begin my ascent up the anchor line.  The ascent takes a little extra effort since I have one hand occupied with a lobster and 10 pound vertebrae.  I do not panic and try follow standard procedures, maintaining a slow ascent and reach the hang bar where I do my recommended 3 minute safety stop.  While on the bar, I look at my dive  computer which is still monitoring the air in my tank and it is registering ‘- – -’  which notes that it is not detecting any air pressure either due to low air or lack of signal.

 

Once back on the boat, I mention to Paul, the captain, and Brad, the divemaster, that my regulator started having problems at the end of my dive and I had resistance breathing.  As I inspect my regulator, Paul opens the valve to my tank.  We hear a light pfffft come out and Paul comments, ‘Yup, you were out of air!’.  Yikes.  I was a little flustered wondering how I got into this situation and preparing for my second dive at the same time.  With an hour plus surface interval, I had time to calm down and review the dive in my head and discuss the matter with Paul and Brad.

 

Here is my breakdown of how I got to here from there.  1) I was wearing a new hood for diving in the cold water.  This hood covered my ears and made it impossible for me to hear my computer’s audible warnings underwater.  This would have been ok if I had the ability to monitor my dive computer.  2) I was using my left hand to hold the lobster against my thigh for the latter half of the dive.  My left hand was also carrying my bag that contained the vertebrae I picked up.  This prevented me from bringing my wrist up to glance at my computer.  3) I was working hard, lugging around a 10 pound fossil as well as a fairly large lobster.  This increased my air consumption.  I thought I had plenty of air based on the last time I checked my computer, and correspondingly, dismissed being out of air as the cause of my regulator problems.

 

Luckily, I had my pony bottle.  In fact, this was my first ocean dive using it.  If I did not have that redundant supply of air, I would have had to ditch my finds and perform a CESA (Controlled Emergency Swimming Ascent) from 90 feet or so, which would not have been pleasant.

 

This experience certainly increased my personal awareness of scuba safety and identifying and preparing for various situations.  1) Always test new gear in a controlled environment before you use it in an open water situation.  If I had put earholes in my hood and been able to hear my dive computer, I may have been able to recognize that I was low on air before reaching a critical point.  2) Be aware of your dive configuration and plan accordingly.  I had everything in my left hand.  This included my 10 pound vertebrae, my lobster, AND my dive computer.  It was impossible for me to monitor my air and dive time properly and I should have adjusted things so I could still do my primary task, check my dive stats and have a safe dive.  3) I was consuming more air than normal because I did not adjust my buoyancy to compensate for the items I was carrying and I had to work harder to swim along the bottom dragging my finds.  I did not expect to run out of air and I denied the fact when it actually occurred.  4) This was a dive I have done many times.  I was complacent with my routine and failed to note that there were differences with this dive.  I should have been aware of these facts and compensated for these changes.

 

Overall, this experience has taught me to be better prepared for a dive, no matter how often I have done it.  I always have my pony bottle on when I dive.  I want to be comfortable wearing it and knowing how to access it if I ever need to use it again.  I always have a reel, light and knife on me.  I also always carry a surface marker buoy (SMB).  When I prepare for a dive, I put my gear together, and always check to make sure everything is working properly.  I validate that I have enough air for the dive and I make sure all of my accessories are working properly.  In the water, I make it a habit to be constantly glancing at my dive computer, looking at the key statistics.  Dive time remaining based on no decompression limits and air pressure, being the most important.  If I am carrying something, such as my camera, I make sure it does not impede my ability to check my dive computer.  I am not the best underwater navigator, but I do validate my general heading using my compass when I start my dive and make sure I follow a path that puts me back near my starting point.  I do not push the limits concerning my air supply or dive time.  There is always a certain amount of a safety margin with my dives to deal with the unexpected.  As I learned in the Boy Scouts, Be Prepared.

 

Hopefully, this is an interesting story for you to read.  But, honestly, I hope this will make you think a little more when you plan and execute your dives.  Be Prepared.  Be Safe.

 

-Frank

 

 

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2 Comments to Overconfidence Always Leads to Trouble

  1. Sandro lima says:

    May 18th, 2011 at 9:18 pm

    This is really scary!!!
    Congrats for the blog.

  2. fyue says:

    June 27th, 2011 at 4:37 pm

    Adam,
    First, thanks for reading and posting your comment on this article!
     
    I concur with your comments and will clarify what you state and what I posted. My primary concern once I determined that my air supply was compromised (in this case being extremely low/out), was to switch to my bailout and end my dive. My finds were absolutely secondary to my safety. I did hold on to them, though, since I had mentally weighed at the time (possibly the wrong decision) that with my pony bottle of air, I had an ample supply to end my dive, make a safety stop and return to the boat. If my pony bottle failed me, I would still have the opportunity to drop the finds and perform an emergency ascent. When I purchased the pony bottle, we did calculations based on maximum depths I would be going to, my SAC (surface air consumption) rate and time needed to safely ascend including a safety stop to ensure that it would provide an adequate air supply. I strongly recommend that anyone using an alternate air source do these calculations. For this reason, I do not believe that the Spare Air products are an adequate bailout mechanism for most recreational divers.
     

    For your second point, I agree wholeheartedly with you. The hood was only one factor to me not properly monitoring my computer/air supply. The fact that I was working harder and no longer had easy access to view my left wrist once I obtained the lobster, was a major reason I was not tracking my resources. Because of the multiple tasks, I neglected to properly monitor my computer. As for not hearing alarms, yes, not hearing them is our ultimate goal! But when they do occur, once needs to immediately focus their attention to the alarm and the reason behind it. I was not able to do this when the alarms occured because of the hood and my lack of hearing.
     

    Taskloading is very evident in this article along with the fact that many small procedural errors lead to one or two real big ones. There is usually not a single event that causes a diver to be in a crisis, but many that compound a situation. The new equipment that caused me to have problems was my hood. I bear responsibility for not testing it properly when I dive. All of the other items that drove me to the scenario in this article were human error based on what I was doing during my dive (over weighted once I found the fossil, using left hand which contains my computer to carry both my bag and the lobster, not properly monitoring my gauge for the second half of the dive and not properly adjusting the dive profile based on my workload).
     

    The pony bottle allowed me to exit this situation without any adverse effects except to my pride. I wrote this report to help people understand how multiple factors that create unsafe scenarios and for divers to take a second look at how they plan and execute their own dives to hopefully prevent accidents of their own. I believe too many divers are unwilling to identify/admit their own mistakes because of the stigma of being considered a ‘bad diver’. There are many more lessons we can learn from each others’ mistakes than telling each other what we did right. A friend used to say that it is easy to learn how to take out an appendix. It takes four years of medical school and an internship to learn how to deal with all the possible complications.

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