Stage Dropping

[Cave Diver]

Referencing the recent thread in A & I: http://www.scubaboard.com/forums/accidents-incidents/385666-fatality-wkp.html

Todd Leonard has been sharing what little info is available on the Cave Diver's forum. Apparently, a deep bottle was dropped at the 70' stop, instead of the 70' bottle. At 120, the switch was made onto the 70' bottle, and it was apparently breathed for about an hour before the seizure occurred.

I'm posting this in light of the recent accident at WKP. I know most of us follow the standard procedure of verifying bottles at gas switches, but I'm curious how many people do it for stage drops as well.

And yes, I realize that this accident wasn't a stage drop per se, but more like a misstep on a deco cache but it started me thinking about other cylinder handling that we take for granted. If the details reported above are accurate, two opportunities to catch the issue were missed, one where the original bottle drop was made at 70' and again when the gas switch was done at 120'.

Is this incident going to affect your personal procedure in any way?

 

[TSandM]

Yes. I am going to insist that we verify the identity of any bottle that is dropped. That in spite of the fact that I only carry an Al40 deco bottle, and use Al80 stages. I still haven't decided whether we need to verify MOD at switches on and off bottom stages.

 

[Dive-aholic]

No changes here. I have very distinguishing attributes to any reg I use for decompression gasses. My 100% has fixed angles and a green hose and my 50% has a different faceplate and a yellow hose. I can verify either by looking at the hose or feeling the angle or faceplate. All bottom gas regs are the same and don't have those specific differences. I don't remember when I began doing that or why, but it was long before I ever moved to Florida.

 

[rjack321]

I already verify stage and deco switches. The only thing we do not verify is going to the long hose. So no changes I can think of.

I had not seen the A&I thread but over an hour on the wrong gas with "support" divers supposedly there at times is really sad.

 

[karstdvr]

. I know most of us follow the standard procedure of verifying bottles at gas switches

Got to wonder how well this is done across the industry. For an organization that made this an obsession to have a mistake,makes me wonder about the general population. I have seen/heard some close calls that by luck there wasn't a fatality. Are we doing enough,and giving the seriousness of this enough consideration.

 

[tstormdiver]

I will be watching this & other similar threads, as I am preparing to begin Trimix later this summer. Taking all the information with a grain of salt, but still giving it serious consideration.

 

[cavemn]

If I were to do a 4 gas dive I am prepared

• A. No one touches my gas and I don't touch someone elses bottle unless it's obvious they have the wrong gas.
• B. My bottles are different colors and have different regs
• C. My bottles are clearly marked with MOD
• D. My 20ft is a different size and green reg with green hose

You can add to this tape on each reg hose near the 2nd stage for more safety(good idea Edd)
Even so, I can see where mistakes might happen. 4 gases is a lot of gas switching and task loading. We practice with stages and gas switching and line technique almost every dive for this very reason.

 

[MXGratefulDiver]

All this incident really proves is that any system ... no matter how well conceived ... is susceptible to error.

Welcome to humanity ...

... Bob (Grateful Diver)

 

[CyprusSeb]

Does anyone label their regs? We label the back of all of our regs when doing multi-stage dives with MOD. Long hose and bungee and all bottom mixes would get "BM" written on the back of the reg (just under the mouth piece...small piece of tape, JUST incase). All deco/travel regs would get the MOD treatment as well as "standard" (<--- using that loosely) bottle markings, then individuals have their own way of distinguishing between their deco mixes aside from all the markings I mentioned.
For example, my 100% bottle has green mesh zip tied to the hose. Very distinct color and with lights out, a very distinct feel. The reg is also a SP MK2 with a 190 so no mistaking the draw on it. My standard 50% regs have a HOG quickshot inflator on the first stage as that's the depth we usually shoot our bags up from. As I do a lot of solo diving as well as team I don't always have the luxury of having someone else verify my reg prior to breathing it. I test and label all of my regs/bottles and even in no/low vis can by feel know which reg I've swapped to.

 

[MXGratefulDiver]

Labels wouldn't work very well in a silt-out ... which is something that cavers need to plan for (at least Florida cavers) ... creating some unique way to identify the gas by feel would be more effective ...

... Bob (Grateful Diver)