Last Weekend's "little" accident

[dumpsterDiver]

Last weekend I loaned a friend a few nitrox tanks and I brought four of my tanks on the boat. First we had to stop off at the shop and get 2 fills of nitrox. I often get tanks filled with air for dives that are too deep for nitrox and they are always labeled as air (or sometimes for dives that are too shallow for nitrox).

Anyway, I did one dive to about 80 feet on 34% nitrox for a while maybe 35-40 minutes. I didn't really look much at the computer because I knew deco considerations were not an issue. An hour later, I grabbed another tank and did a solo dive in 100 feet max with an average of maybe 85-88 ft for a while, I'm not sure how long.. maybe 30 minutes, maybe a little longer. Again, I was not really watching my dive time, because I have been doing dives like this for so long.. I pretty much KNOW that I don't really have to watch elapsed time...but I was keeping an eye on my no deco limit.

The last number I remember seeing on my computer was 15 minutes of no deco time, but I might have stayed for 3-4 minutes more. I still had some gas, but I shot a decent fish and it was bleeding all over and I had drifted off the wreck, so I went up earlier than I would normally do (I probably had 900 psi in a big steel tank left).

Since I dive solo and carry a pony, I can run my primary tank down pretty low and make a safe ascent (don't have to worry about saving air for a buddy in an emergency) So, I could have easily stayed several more minutes and started the ascent with 350-400 psi (if I had a reason to do so). In all honesty, I probably would have done that, if I had not got the fish toward the end of the dive.

I did a deep stop at 50 for a minute or so and then a 3 minute safety stop at 20.. A conservative dive (definitely shorter than my gas supply or my deco limit constraints.)....I never adjusted the mix on my computer from the first to the second dive.

As I was breaking down my tank an hour later I happened to look at my tank. I had (for some reason) assumed (thought) that all the tanks I brought were 34% nitrox. I always check the label of the mix when I set up my tank.. But apparently NOT this day. It was marked as AIR..:depressed:... I know I NEVER intended to load into the truck an AIR tank, ALL the other tanks were 34%, except this one tank. I made an error when half asleep at 6:40 am while loading the truck.

How stupid is that? I've been diving nitrox for maybe 15 years; many hundreds if not a thousand times,,, and still screwed up.. All I can blame it on is complacency. No amount of training would have helped me..

I am never one to shy away from giving people crap for doing stupid stuff, so I kinda felt some sort of obligation to fess up......Be careful!

 

[antattack]

Rather than all of us ranting and raving about planning your dive, and diving your plan, checking your gear etc.... What lessons do you take away from this experience?

so glad your dives were pleasant and ended without inicident. Thank you for the imporatant reminder!

 

[DevonDiver]

All I can blame it on is complacency. No amount of training would have helped me..

The success, or failure, of training is attributable to whether that training is effectively applied thereafter. Experienced divers understand the threat of complacency - because we've all learned those lessons at one time or another.

Complacency (and it's impact of degrading safety protocols) is something that training should address. Where training contains formal protocols, they should become a standardized routine for the diver. No exceptions. Nobody is beyond making human error, none of us. Adherence to formal protocols ensures a fail-safe for when that human error occurs.... be it in 10 dives, or 1000 dives in the future...

Glad you didn't get hurt.... and thanks for sharing that experience. Given your experience and confidence, it's a vital lesson to share with newer divers.

 

[dumpsterDiver]

The success, or failure, of training is attributable to whether that training is effectively applied thereafter. Experienced divers understand the threat of complacency - because we've all learned those lessons at one time or another.

Complacency (and it's impact of degrading safety protocols) is something that training should address. Where training contains formal protocols, they should become a standardized routine for the diver. No exceptions. Nobody is beyond making human error, none of us. Adherence to formal protocols ensures a fail-safe for when that human error occurs.... be it in 10 dives, or 1000 dives in the future...

Glad you didn't get hurt.... and thanks for sharing that experience. Given your experience and confidence, it's a vital lesson to share with newer divers.

My comments about training are that I KNOW what should be done. It is my own fault and responsibility. My knowledge of all the deaths of many divers from "the wrong gas" as well as my training and common sense all dictate that I should look at a little piece of tape on the tank.

Maybe my thoughts are better expressed as: "no amount of training (or education) is an antidote for stupidity". I have been saying that little phrase for so long, I'm not sure I if I made it up or heard it somewhere..

If I had made the reverse error and done a "deep air" dive with one of the 34% mixes, somebody else would probably have to "write the story"... simple as that...

 

[rhwestfall]

DD:

Thanks for the slap in the head reminder! Glad all is well...

 

[dlofting]

Thanks for posting DD. I think "stupidity" is a bit of a harsh word in this case and "complacency" is more like it......something that I know I have to watch out for, given my tendency to "zone out" mentally when I'm doing something I've done many times before.

 

[danvolker]

This is one time you can be happy you did the deep stop, and then the several minute safety stop--as these were effectively real decompression stops for you....

And apparently they were sufficient deco.

 

[agilis]

What kind of dives are too shallow for Nitrox?

 

[danvolker]

What kind of dives are too shallow for Nitrox?

At the BHB Marine Park, av depth 8 to 16 feet deep, Nitrox is a silly wasted expense....and for divers doing 3 to 5 days in a row there, 4 to 5 hours per day ( Sandra has done this) Nitrox can cause Hyperoxic Myopia....

 

[David Kirberger]

Rather than all of us ranting and raving about planning your dive, and diving your plan, checking your gear etc.... What lessons do you take away from this experience?

so glad your dives were pleasant and ended without inicident. Thank you for the imporatant reminder!

Well played, sir.

I was just about to post "Any dive you can walk away from, etc... but what will you do differently next time." kind of comment.

I have just a fraction of the dives that dumpster has, but in the end, we are all still learning, aren't we?