OOA after only a few minutes with a full tank at 17m

[The Chairman]

yet this process puts a lot of people at risk to this day

OMG!!! Can you get any more hysterical? The biggest and only risk is that they'll have their tank valve open.

You are the most knowledgeable person on this forum.

Bwahahaha! No, not even close but thanks for the compliment. I might be one of the most opinionated persons on SB, but I'm not the most knowledgeable. That being said, I do teach VIP and we cover this ongoing non-controversey.

but that loose knob to other divers youve trained could easily be a quarter turn open

That makes no sense. No sense at all. The same can be said about a closed knob. If you aren't good with CW vs CCW, then get Vindicator knobs. That's the real problem here. Loose or not loose will not resolve this one whit.

It’s amazing this can be so over analyzed and group think still comes up with the wrong answer.

Ain't that the truth, and that's an excellent post!

BTW, it would behoove everyone to learn how to turn your tank on in water. Loosen your waist, reach back with your left hand, grab the first stage, pull it forward and then reach back and turn the valve.

Please... if you see someone on a boat or a shore dive who backs off their valve a bit, DON'T GO BANANAS ON THEM!!! I don't care how dangerous you think this practice is. It's not and this is a "Dive and let dive" situation. Don't let your unreasonable fear destroy the camaraderie of the dive. I've actually had that happen and boy was it an uncomfortable situation. They even told my students that I was an "uncompetent" instructor, which drew a laugh. Develop a process, a routine if you will, and stick with it. If your buddy wants to chat and you're not set up, tell them to give you a minute so you can concentrate on setting up first. FWIW, one of the buddy checks I teach is to listen to your buddy breath on their regs. If you didn't hear them breath on them, simply ask and tell them it will make you feel better. You might tell them that you look at your SPG when you do, but at least listen to them breathe.

 

[tarponchik]

I had a longtime experience with industrial gas tanks, and now I even turn my outside water faucet valve a quater back when I open it to sprinkle flowers.

Another hint: If you are right-handed, do not open or close your tank with your left hand. Hands tend to work symmetrically, so what is clockwise for your right hand is counter-clockwise for your left, etc. My guess is this is what could have happened in this case.

 

[Graeme Fraser]

OMG!!! Can you get any more hysterical? The biggest and only risk is that they'll have their tank valve open.

Bwahahaha! No, not even close but thanks for the compliment. I might be one of the most opinionated persons on SB, but I'm not the most knowledgeable. That being said, I do teach VIP and we cover this ongoing non-controversey.

That makes no sense. No sense at all. The same can be said about a closed knob. If you aren't good with CW vs CCW, then get Vindicator knobs. That's the real problem here. Loose or not loose will not resolve this one whit.


Ain't that the truth, and that's an excellent post!

BTW, it would behoove everyone to learn hot to turn your tank on in water. Loosen your waist, reach back with your left hand, grab the first stage, pull it forward and then reach back and turn the valve.

Please... if you see someone on a boat or a shore dive who backs off their valve a bit, DON'T GO BANANAS ON THEM!!! I don't care how dangerous you think this practice is. It's not and this is a "Dive and let dive" situation. Don't let your unreasonable fear destroy the camaraderie of the dive. I've actually had that happen and boy was it an uncomfortable situation. They even told my students that I was an "uncompetent" instructor, which drew a laugh. Develop a process, a routine if you will, and stick with it. If your buddy wants to chat and you're not set up, tell them to give you a minute so you can concentrate on setting up first. FWIW, one of the buddy checks I teach is to listen to your buddy breath on their regs. If you didn't hear them breath on them, simply ask and tell them it will make you feel better. You might tell them that you look at your SPG when you do, but at least listen to them breathe.

Fully agree on all counts, in particular learning how to manipulate your valve / knob underwater.

 

[Miyaru]

 

[rsingler]

As to why I crack back a tiny bit, no real reason apart from it feels the right thing to do to me, rather than leaving it hard on the stop.

As the guy who, after 30+ years of diving, changed his practice on the basis of this discussion (how many times have I been here??), one thing stands out as an Instructor: I might save a life through a practice that permits only one of two conditions (assuming only that you prebreathe your regs before you splash). You will have air or you won't. If you only allow your valve fully open or fully closed, those are the ONLY two options.
As a reg technician, it still bothers me to leave a valve against the stop. I'll get over it. My practice may end up with a broken handle if a gorilla touches my gear without me knowing it.
But I can tell my students now, you WILL make mistakes. But if you only allow one of those two conditions: valve completely on or completely off, then when you prebreathe before jumping, you will know you will have air, both at the surface and with thick air at depth.
As rare as the partially open valve mistake might be (think Sheck Exley), I'll accept the rare valve damage from over-tightening over the alternative now. In this case, I've gotta let my OCD over perfect gear go.

 

[doctormike]

As the guy who, after 30+ years of diving, changed his practice on the basis of this discussion .

Hang on, everybody. We need to reboot the Internet. This has never happened before....

 

[Bob DBF]

But I can tell my students now, you WILL make mistakes. But if you only allow one of those two conditions: valve completely on or completely off, then when you prebreathe before jumping, you will know you will have air, both at the surface and with thick air at depth.

And you insure you are the only one that lays a hand on that valve. The problem does not have to be self generated, or follow your rules.



Bob

 

[DeepSeaExplorer]

And the solution, to alleviate unnecessary confusion, is to get rid of the backing off altogether.

Using dive tables is confusing to new divers, but we still make them do it anyway.

I don’t think this was a back off issue. This was someone that only opened the valve part way because they weren’t paying enough attention, didn’t know better, or someone was trying to help and turned it the wrong way.

Watch the DM on a boat check divers as they get in the water. If the valve is backed off, s/he immediately knows the valve is open and moves to the next diver. If the valve is full open, s/he works the valve, by trying to open it, then goes back toward closed and then realizes it’s full open, then maybe goes back to full open, sometimes not. The back off gives immediate feedback that the valve is open. Those that don’t do it, risk having their valve turned back by the DM.

Divers are a diverse group. There are more than a few that have never worked a valve before becoming a diver. It’s all very new to them and mistakes will be made.

My wife still gets confused sometimes and more than once has asked me how I always know which way to turn the valve. (I always double check her.)

 

[rsingler]

Watch the DM on a boat check divers as they get in the water. If the valve is backed off, s/he immediately knows the valve is open and moves to the next diver. If the valve is full open, s/he works the valve, by trying to open it, then goes back toward closed and then realizes it’s full open, then maybe goes back to full open, sometimes not. The back off gives immediate feedback that the valve is open. Those that don’t do it, risk having their valve turned back by the DM.

This was EXACTLY my prior reasoning. You're not wrong. But if the DM gets it wrong (and we've had more than one report in this very thread of crew turning the valve toward off), then you're STILL left with a partially closed, or worse - a partially open valve that is exactly what got the OP into trouble.
As a hardheaded guy who went through the same rationalisation that you are going through, your reasoning may be sound. But it doesn't matter. If you have a valve that you only leave completely on or completely off, if you prebreathe your regs, and if you recheck any time anyone touches your gear, including the DM, then what happened to the OP won't happen to you.
Look at your logic, as I did. I hope you will conclude that the only guarantee against a mishap is eliminating a partially open condition. Once you've done so, a few breaths off your reg and you will have absolute surety that barring a separate failure, your regs will deliver air at depth.
Rather than become a POV warrior for my new practice, I think I'll leave it at that in this thread.
Thanks to all for helping me reset my priorities.

 

[Jcp2]

Is there a place for a valve knob that is shaped in such a way that it feels different when turning one direction versus the other?