Interesting air management...

[IndigoBlue]

The author said he thumbed the dive.

One rule that I was taught ... and will emphasize in my classes ... is that when one team member thumbs the dive, the dive is over. If you have any questions, ask them on the surface.

... Bob (Grateful Diver)

I agree, that it is common courtesy to surface, when your buddy wants to surface. A safety stop should not be skipped, unless there is some danger in performing it. 50 bar should be plenty to do a 3 min safety stop at 15 ft.

If there was some reason that these divers though it was not prudent to surface, then they were on a de facto overhead-obscured dive, and they should not have been. That should have been a site selection issue, and if it were true, they were probably diving at the wrong site. But I do not believe it was true.

Dive club politics is a problem in every dive club. Sometimes its better to bring your own buddy, someone you can trust, to a dive club, just like on a boat. Of course, the reason people join dive clubs is to find a buddy in the first place.

Chicken and egg problem here.

 

[Scuba_Vixen]

Isn't that exactly what they did? Analyze the situation performed a direct egress?



Clearly, the diver giving the thumbs up was not in distress, not the group leader, and not the buddy of the diver who was low on air. Also, clearly unfamiliar with their standard procedures.

Remember recreational divers may not be trained to view a thumbs-up as an absolute command. They are often beginners, less disciplined and rigorously trained than technical divers and some signals may be given at inappropriate times, in unsafe conditions, or for the wrong reason. I think it is appropriate to analyze a situation before blindly acting (which apparently is exactly what a technical diver would do as well).
Ralph

In my post that you quote, you'll see I was specifically addressing the questions asked by a previous poster:

"Originally Posted by rcohn
I'm just a recreational level diver so let me see if I understand how the technical community uses the thumbs up sign. Does the thumbs-up sign mean turn the dive now or directly ascend to the surface without consideration of any safety/practical issues?"

Recreational divers often have unique hand signals or second meanings for standard ones that can confuse the pimikin out of other divers. The thumb up for "wayyyy cooool" being the most common, but usually discernable from the context of what's going on.

The bigger issue here, and one that should have been covered in the pre dive briefing, was that the group did not consider the need to go to air sharing to be an automatic dive ending event. Most of us do, expert perhaps if it's safer below the surface than on it. Recreationally speaking, "dive ending" means going to the surface, Now, not 25 yards closer to shore.

Hope that clarifies,

Darlene

 

[Dan Gibson]

There is the problem. Thumbs is thumbs should be taught from the start, no excuses. It should be drilled into their heads as much as the "always blowing bubbles when a reg is out of your mouth" (which isn't always correct).

What would you do if you asked if your buddy really meant it and then he changed his mind. Then moments later he may really be in trouble because he was not really in any condition to change his original decision. Maybe technical divers realize this a don't take such a gamble.

You can always dive another day if you make the more conservative call. If you don't, you may not be around to have that choice another day. If you are diving recreationally and it's early in the dive, you can always go back down after surfacing and discussing it.

Remember recreational divers may not be trained to view a thumbs-up as an absolute command. They are often beginners, less disciplined and rigorously trained than technical divers and some signals may be given at inappropriate times, in unsafe conditions, or for the wrong reason. I think it is appropriate to analyze a situation before blindly acting (which apparently is exactly what a technical diver would do as well).

Ralph

 

[rcohn]

What would you do if you asked if your buddy really meant it and then he changed his mind. Then moments later he may really be in trouble because he was not really in any condition to change his original decision. Maybe technical divers realize this a don't take such a gamble.

Tech diving question. You have a 20 minute bottom time at 260 ft on a wreck in strong current. You buddy signals thumbs up. Are you going to shoot directly to the surface at top speed, blowing off your deco stops? How do you know he hasn't begun to have a heart attack and must surface immediately? Shouldn’t you make the most conservative possible decision and assume he is about to die? If you aren’t willing to blow off a little deco to save your buddy’s life why are you doing a decompression dive in the first place? You can always dive another day if you survive the hit.

Thumbs up might mean here:
1) Move upward to a shallower point on the wreck and then level off.
2) Return to the ascent line and end the dive.
3) Leave the wreck immediately and do a drifting deco.
4) Shoot to the surface directly for a medical emergency
5) Other….

It just doesn’t seem so simple to me.

Ralph

 

[garyfotodiver]

Tech diving question.

The original discussion wasn't about a 260fsw wreck dive, nor about a 1500ft cave exploration. It was about an open water dive by members of a university club. The description cited made it clear to me, and to others on the board, that some of the divers lacked basic skills. I can hardly see wreck or cave divers not having an effective set of signals established brfore the dive.

Why not take the ancillary discussions off to another thread?

 

[MikeFerrara]

Tech diving question. You have a 20 minute bottom time at 260 ft on a wreck in strong current. You buddy signals thumbs up. Are you going to shoot directly to the surface at top speed, blowing off your deco stops? How do you know he hasn't begun to have a heart attack and must surface immediately? Shouldn’t you make the most conservative possible decision and assume he is about to die? If you aren’t willing to blow off a little deco to save your buddy’s life why are you doing a decompression dive in the first place? You can always dive another day if you survive the hit.

Thumbs up might mean here:
1) Move upward to a shallower point on the wreck and then level off.
2) Return to the ascent line and end the dive.
3) Leave the wreck immediately and do a drifting deco.
4) Shoot to the surface directly for a medical emergency
5) Other….

It just doesn’t seem so simple to me.

Ralph

It is pretty simple. When we just want to casually turn a dive but there isn't a problem or a hurry, we use a signal for "turn". We have a signal for end the dive now but return to the entry point or descent line which is the thumb with a pointing index finger. When we use the "thumb" it means go up. Period. It does not mean skip decompression though. We don't have a signal for that but I'm gussing that if I ever need to blow off decompression I'll know it.

 

[MXGratefulDiver]

Each of these uses a different sequence of signals ...

1) Move upward to a shallower point on the wreck and then level off.

Thumb up, followed by a numerical indication of desired depth (example, two-zero), followed by a horizontal hand slash (standard "level off" signal).

2) Return to the ascent line and end the dive.

Point in the direction of the ascent line with thumb extended upward.

3) Leave the wreck immediately and do a drifting deco.

A combination of 1 and 2 ... pointing in the direction of the current with thumb extended, followed by a numerical indication of desired deco stop depth and the hand slash.

4) Shoot to the surface directly for a medical emergency

Two thumbs up ... emphatically!

It just doesn’t seem so simple to me.

Hand signals, like any other language, must first be learned ... then practiced.

... Bob (Grateful Diver)