A CO2 incident avoided...through luck!

mik

After having commended others for posting their incidents, I have swallowed my pride to post this, even though I feel very stupid for my mistakes.

I emptied the last of a 20kg tub of Sofnolime into my scrubber before my last dive. It was not quite as full as I normally would fill it but I had no more and I planned on diving the next day. We are not talking a large amount of spare room in the scrubber here but more than normal. I tightened up the spider then continued with pre-dive checks as usual.

Next day I did the dive and as I was solo for the first time in a while, I decided to do some drills throughout. I planned on 1hr at max depth of 23m.

I stopped at 6m, spiked my PPO2 to 1.6, dil flushed and bailed out a couple of times then descended to continue the dive. I continued bailout and dil flush drills throughout the outward leg of the dive.

About 15 minutes in, I got a bit cold and started my return to the anchor line. It was about here that I started to get a bit choked-up and found it a little hard to breathe. I did a dil flush and all seemed to be well. Did I mention that I had a mild cold?

I continued on and a few minutes later, I noticed that I felt warm and that I was panting slightly so I did another dil flush then went open circuit. I would like to say that I called the dive and ascended but, alas, I literally experienced a moment of clarity and went CC again to return to the anchor.

My brothers were waiting on the boat for me, and as they do not dive, I like to make my dives as painless as possible for them which includes returning the 35lb anchor to the surface on a lift bag. I remember thinking that it was very hard work moving the anchor and experienced a slight dimming of vision as I lifted it from its cosseted hollow between two rocks, even though I normally lift it fairly easily. I also struggled with inflating both the lift bag and my SMB, these tasks seemingly more difficult than usual.

The real *****les-on-the-back-of-my-neck feeling came after I had cleaned my gear and I was reinserting the scrubber canister. I noticed, with some alarm that there were not the usual bulges of Sofnolime in between the gaps of the spider. When I touched the scrubber material through the scrims, I noticed that it was very un-uniform, that some lumps of the Sofnolime were pressed against the scrim while other areas made no contact with the scrim at all. On shaking, it sounded like a hula girl's maraca! I emptied it into the bin so I would have no temptation to dive on that scrubber again - like I needed the extra push!

I feel so stupid for under-packing the scrubber in the first place because of insufficient forethought and continuing to dive CC after experiencing symptoms of hypercapnia. My focus on doing the dive overrode my misgivings about the scrubber and I found the symptoms of hypercapnia very insidious, particularly combined with skills practice which diminished and delayed their effect. I also had a cold as another factor which I used to dismiss hypercapnic symptoms.

I have no doubt that I was affected by CO2 on this dive but fortunately, or unfortunately, the effects were partially masked and diminished by my skills practice, which ironically made me less safe on this dive! I am at that 30-50 hour window where so many have slipped-up in the past and I hope that my lucky escape will serve as a warning to others.

Michael

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It just fell apart in my hands, Chief!

jhaaja

Thanks for the write up and good that you made it back to the surface!

Did you find it hard to control your breathing while changing from CC to OC?

Did you shake the scrubber bucket after filling to make sure it is tightly packed?

JH
Finland

caveseeker7

Complacency is a bitch, ain't it! Thanks for the reminder.

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Cheers
Stefan



"Political Correctness is a doctrine, fostered by a delusional, illogical minority, and rabidly promoted by an unscrupulous mainstream media,
which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.'!"

CharlieT

Thank goodness you are safe.

That's all that really matters!

Thank you for sharing this incident with us.

mik

I was 'just' panting. I think that I must be one of those few people particularly susceptible to CO2 build-up as I have noticed it when working very hard on OC. I did not find the actual switch to OC difficult, just the cognitive ability to recognise that I needed to. I was kind of telling myself that everything was fine and ignoring the effects. That is what I meant about the insidious effects. The physical act was easy but getting the desire to do it was hard.

I did shake the scrubber after filling it and it was OK but I had not tapped it down as much as usual. Remember I only had what sofnolime was in there. Dumb...

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It just fell apart in my hands, Chief!

KevDD

My thoughts exactly. It really is a bitch. Glad it didn't cost someone their life this time.

Bobmac

Thanks for posting this. It's provided me and I'm sure other people with a strong reminder of what can happen to anyone.

ScubaDadMiami

Thanks for sharing your experience. Hopefully, someone will not repeat the misadventure.

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Howard Packer
IANTD CCR Instructor
Miami Beach, Florida
CCRDiveTraining.com

Dutchy

Couldn't have said it better. Thx (be greened) for taking the time to write up the story...

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Dsix36

Have some green for the courage to post your close call!

May we all learn from this.

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THE MORE THAT I LEARN, THE MORE THAT I STILL NEED TO LEARN!!!!!!