Archaeological dive incident

[rx7diver]

I think it was good that you didn't dive the tank, but how did you know the air tank was air, if it came from the same place?

FWIW, I routinely analyze my *air* fills if they come from a shop that dispenses nitrox also. (I'm not sure how common this degree of paranoia is, though.)

rx7diver

 

[vladimir]

rs86,

Not what you asked about, but a quick comment: My understanding is that no one is obligated to supply you with an oxygen analyzer with which to check your nitrox (although many nitrox vendors will allow you to use theirs). If you dive nitrox, you ought to have your own analyzer.

I have no reason to believe they are obligated to, but the general practice seems to be that nitrox suppliers have analyzers available. I do have my own analyzer, but that does not seem to be the norm, in my experience. And I have yet to get a tank of nitrox from somebody who couldn't supply an analyzer.

 

[Codiak]

You stuck to your Nitrox training and refused to dive an unknown gas, good for you.

As for thumbing the dive.... There is no debate, no discussion, no explanation required until you are on the way up. Buddies who question a thumb aren't people you need to dive with.

Hopefully you've learned the lesson of carrying appropriate equipment.

 

[rs86]

Thanks everyone, I realised what I did wrong, and I will definitely make sure I have an SMB next time diving off a boat, and surface whenever I see fit...

@Dumpsterdiver: That's not what is being taught in training. Everyone makes mistakes, and a mistake with filling or analyzing an EANx tank can easily get you seriously injured or killed. It's not smart to trust anyone on this, especially people you don't know... Would you take a pil from some random stranger you meet on the street just because he says it doesn't do any harm?

 

[JG109]

Congrats on handling the dive without injury.
I agree with you not using the nitrox without analyzing. There was a fatality posted on here ref an improper mix (tech dive but same principle).
I always carry a smb/finger reel. You can stow the smb on your bc, lower back area with bungies. You don't even feel it there. I hope you will too.
As they say "Experience is a hard master".

JG

 

[Thalassamania]

There are a number of lessons here:

1. Equip yourself, if your going to dive EAN, get your own analyzer, carry your own SMB, pony, whatever you think you might need to complete your dive with minimal risk.
2. Get a copy (from Best Books?) of the UNESCO International Code of Practice for Scientific Diving, it has a good section on the managing archeological dives.
3. Based on the UNESCO manual develop a team to dive with you that dives as a team, most of this kind of foolishness can be avoided by diving with people on a routine basis.
4. And there's that old saw: plan you dive and dive your plan.
5. When it starts to go south, for any reason, thumb the dive and start again tomorrow with a new plan that accounts for the problem you encountered.

 

[Codiak]

@Dumpsterdiver: That's not what is being taught in training. Everyone makes mistakes, and a mistake with filling or analyzing an EANx tank can easily get you seriously injured or killed. It's not smart to trust anyone on this, especially people you don't know... Would you take a pil from some random stranger you meet on the street just because he says it doesn't do any harm?

Sarcasm is strong with that one

 

[dumpsterDiver]

..@Dumpsterdiver: That's not what is being taught in training. Everyone makes mistakes, and a mistake with filling or analyzing an EANx tank can easily get you seriously injured or killed. It's not smart to trust anyone on this, especially people you don't know... Would you take a pil from some random stranger you meet on the street just because he says it doesn't do any harm?

I don't really care what is being taught in a class. My point was that you were willing to trust your life to strangers underwater who seemed to have very little regard for your safety, yet you don't trust them (or the tank mixer) to give you a proper fill.


If that what is taught in a class, I think you should re-examine it. Which is more dangerous (when you are carrying zero redundant gear) to trust someone to stick with you through all the complexities of a challenging deep dive in bad vis or to mix a freaking tank?

Also as someone else mentioned, you dove an "air" tank from the guys who had nitrox tanks, yet you never checked the contents of the "air" tank. I know, i know, they teach you in the class that this is prefectly fine because ????? people never make mistakes and mix up a nitrox and an air tank right?

I personally will trust another person to check the mix of a tank that i use, I do it commonly actually, but as mentioned previously..I KNOW THEM.. We trust our lives to other people all the time..ever fly in a commercial aircraft or ride in abus or a taxi?

I think it is somewhat silly to refuse a tank because you didn't check it, yet you blindly buddy up with people you have no reason to trust, yet you dive with zero redundancy.

 

[dave2063]

Always be safe. never risk your life for some stupid anchor.

but regarding the anchor.......

the guys could stick a marker line and buoy on the anchor for next time, searching for an anchor at 34m is not good.

you can then just drop down the line to take a look at the anchor, otherwise just give them a videocamera and get them to take video and/or measurements....

safe diving.

Tuna

 

[boulderjohn]

As someone who has filled a large number of mixed gas tanks using partial pressure, I assure you that it is really easy for someone to make a mistake. There was a fairly famous incident in Croatia in which the guy who blended all the gases for everyone made a mistake and added O2 to his own tanks twice instead of adding O2 and helium. Being the guy doing the filling, he did not analyze his own tanks. Fortunately he realized the error when he had the preliminary symptoms of oxygen toxicity and signaled for help in time to have someone already starting to share air with him just as he had his first seizure. That person was able to bring him to the surface successfully, a rare event in oxygen toxicity cases.

I trust myself with my life, but I analyze the tanks I blend, too.