Yukon tangent thread

[Blow.Fish]

Anyway. It doesn't take a "divemaster" or a cop, or a lawyer or a judge to figure out that someone out of air at 100ft, who also can't make it to the surface, is dead unless something drastic takes place in five minutes.

Anyone with a watch can tell you that it's impossible to notice a lack of bubbles, change a tank, descend 100ft, find a body, and bring it to the surface safely in five minutes.

I was thinking the same thing. Take a hypothetical best case scenario, for example - A day with perfect topside and underwater conditions with top-bottom visibility. A boat-based DM is standing on plantform and in visual contact with a diver 100ft below. The attentive DM notices the very second that the diver's bubbles have stopped and springs immediately into action.

What is the shortest amount of time that it could possibly take for a highly skilled and efficient divemaster to don gear, descend to 100ft, recover diver, then make a prompt but safe open-water ascent to surface and then begin CPR ...4-5 minutes in the best case ? That's a guess on my part.

Now put it in the context of this incident - a deep(er) cold water wreck site, with low(er) viz and minimal information regarding the missing diver's exact location. What's the best case now assuming same DM ...6-8+ minutes ? What's realistic...10-15+ minutes ? Again, I'm guessing.

Don't get me wrong, I am in no way excusing the actions of the crew of this boat. Leaving the site without knowing that a diver is missing is 100% unacceptable. However, I tend to agree with others that it likely had little bearing on the final outcome other than delay the recovery of the body. Two extremely unfortunate but orthogonal events.

Regardless, it is a very sad situation for all parties involved. My condolences to all.

 

[Thalassamania]

2 minutes don gear and get to bottom (don tank on the way down, or if you're really good you go down freediving, then it's only about a minute.)
2 minutes up, begin mouth to snorkel immediately.
1 minute to get victim aboard
Start External Cardiac Massage.

Best possible case: 4 to 5 minutes.

 

[lamont]

2 minutes don gear and get to bottom (don tank on the way down, or if you're really good you go down freediving, then it's only about a minute.)
2 minutes up, begin mouth to snorkel immediately.
1 minute to get victim aboard
Start External Cardiac Massage.

Best possible case: 4 to 5 minutes.

That's assuming that you are psychic and know that there's an emergency.

More likely 20+ minutes of the DM and captain helping everyone else on board before noticing that the missing diver has been gone for too long. A lot of grilling of "hey, when do you last see so-and-so?" would occur. Probably at least 10-15 minutes before the anxiety levels hit them point that someone would go down looking for them, best case. That makes it ~35 minutes best-case. At which point the diver is not going to have ventricular fibrillation and an AED is going to be worthless and you're stuck doing CPR on a diver that has been dead for ~45 minutes up until the coast guard arrives.

No way that works.

Your only hope is that another diver sees him within minutes of the OOA... OR TO JUST PREVENT THE OOA IN THE FIRST PLACE. The DM and Captain aren't there to make your dive survivable if you don't watch your own gas, and all the laws and lawsuits in the world can't make it safe to dive and ignore your gas.

The best information on this accident is that he was found on the bottom with 0 psi (and that is as good as the information that we have on no roll call, so if you we can't trust that we can't trust any information at all, at which point this entire thread is utterly and completely pointless), and that situation has a simple cause, a simple assignment of fault and a simple way to avoid winding up there. That explanation doesn't leave anyone else to get angry at and/or to sue, though, so in America it can't be right since we have to blame someone else...

 

[lamont]

I think it's entirely appropriate to discuss whether a formal roll call had been conducted prior to the Humboldt leaving the dive site. This could have affected response time for the overdue diver, especially considering that the guy was using an AL80 (as reported in this thread by another diver on the Humboldt).

We don't know whether the victim was able to reach the surface during the incident. News reports state that he was recovered on the sandy bottom but we really don't know what happened prior to that. This is the main reason I'm curious about his dive profile. If he was wearing a computer that was recording time and pressure data, the info would prove to be very useful in determining whether the boat could have done something more to help the diver.

You've kind of got that backwards. Since he had an Al80 that means he ran OOG when the boat was still over the divesite (he had about 30 mins of gas, and I'm sure the boat didn't get everyone back on board and head off before that time expired). If he surfaced, then he didn't attract any attention and sank due to inability to ditch or orally inflate. Either way, as he was dying, nobody on the surface knew what was going on. That means that you first start the clock for when (busy) people first notice that he's overdue, and then start the clock for them to get alarmed about him being overdue, and then start the clock for going down and finding him. It doesn't get any better than about 30 minutes.

 

[diverrex]

2 minutes don gear and get to bottom (don tank on the way down, or if you're really good you go down freediving, then it's only about a minute.)
2 minutes up, begin mouth to snorkel immediately.
1 minute to get victim aboard
Start External Cardiac Massage.

Best possible case: 4 to 5 minutes.

And you happened to find him instantly?

 

[Thalassamania]

That's assuming that you are psychic and know that there's an emergency.

More likely 20+ minutes of the DM and captain helping everyone else on board before noticing that the missing diver has been gone for too long. A lot of grilling of "hey, when do you last see so-and-so?" would occur. Probably at least 10-15 minutes before the anxiety levels hit them point that someone would go down looking for them, best case. That makes it ~35 minutes best-case. At which point the diver is not going to have ventricular fibrillation and an AED is going to be worthless and you're stuck doing CPR on a diver that has been dead for ~45 minutes up until the coast guard arrives.

No way that works.

Your only hope is that another diver sees him within minutes of the OOA... OR TO JUST PREVENT THE OOA IN THE FIRST PLACE. The DM and Captain aren't there to make your dive survivable if you don't watch your own gas, and all the laws and lawsuits in the world can't make it safe to dive and ignore your gas.

The best information on this accident is that he was found on the bottom with 0 psi (and that is as good as the information that we have on no roll call, so if you we can't trust that we can't trust any information at all, at which point this entire thread is utterly and completely pointless), and that situation has a simple cause, a simple assignment of fault and a simple way to avoid winding up there. That explanation doesn't leave anyone else to get angry at and/or to sue, though, so in America it can't be right since we have to blame someone else...

Lamont, I'm just responding to the proposed scenario exactly as described, Blow Fish did forget adding some time for victim recovery to the vessel:

I was thinking the same thing. Take a hypothetical best case scenario, for example - A day with perfect topside and underwater conditions with top-bottom visibility. A boat-based DM is standing on plantform and in visual contact with a diver 100ft below. The attentive DM notices the very second that the diver's bubbles have stopped and springs immediately into action.

What is the shortest amount of time that it could possibly take for a highly skilled and efficient divemaster to don gear, descend to 100ft, recover diver, then make a prompt but safe open-water ascent to surface and then begin CPR ...4-5 minutes in the best case ? That's a guess on my part.

...

2 minutes don gear and get to bottom (don tank on the way down, or if you're really good you go down freediving, then it's only about a minute.)
2 minutes up, begin mouth to snorkel immediately.
1 minute to get victim aboard
Start External Cardiac Massage.

Best possible case: 4 to 5 minutes.

 

[lamont]

Lamont, I'm just responding to the proposed scenario exactly as described, Blow Fish did forget adding some time for victim recovery to the vessel:

Yeah, that started as a reply to you and turned into a rant to the thread... Wasn't directed at you...

 

[Blow.Fish]

And you happened to find him instantly?

We were assuming that absolute BEST case what-if scenario. While certainly not realistic, it does illustrate that your odds of surviving (w/out serious medical complications) from a boat-based initiated rescue are not very good to begin with... even with flawless execution.

 

[diverrex]

We were assuming that absolute BEST case what-if scenario. While certainly not realistic, it does illustrate that your odds of surviving (w/out serious medical complications) from a boat-based initiated rescue are not very good to begin with... even with flawless execution.

Okay, I see, I reread your original post. Yeah the point is if you have to count on someone up on the boat coming to pull you off the bottom, its not very likely you survive. All of these discussions are very hypothetical, it sure would be nice to know what his computer says.

 

[Bubbletrubble]

You've kind of got that backwards. Since he had an Al80 that means he ran OOG when the boat was still over the divesite (he had about 30 mins of gas, and I'm sure the boat didn't get everyone back on board and head off before that time expired). If he surfaced, then he didn't attract any attention and sank due to inability to ditch or orally inflate. Either way, as he was dying, nobody on the surface knew what was going on. That means that you first start the clock for when (busy) people first notice that he's overdue, and then start the clock for them to get alarmed about him being overdue, and then start the clock for going down and finding him. It doesn't get any better than about 30 minutes.

@lamont: You've made a lot of assumptions in your assessment.
We don't have detailed information regarding his profile. We don't know when the diver entered the water relative to when the boat left the site.
There was a report that other divers underwater observed him looking at something in the sand, but we don't know how long or when he was at that depth.
Before leaving a dive site, the crew busy themselves with operational tasks (storing gear, untying the mooring line, etc.) that they normally would not be doing if they were watching the water for an overdue diver.

Given the information regarding the incident, it's too early to say whether the boat leaving the dive site may have caused the crew to miss out on an opportunity to help the victim.

At the very least, the boat leaving the dive site delayed initiation of a search for the man.