Tank valve opening procedure

[Rick Murchison]

You really haven't lived 'til you've had one stick open so hard that the valve handle fails trying to close it. I've seen that.
I make sure my valve's not against the full open stop... a quarter turn feels comfy.
Rick

 

[Toolbox-13]

I do the full open and back off 1/4 turn. Its a habbit thing for me also

 

[spectrum]

I open it all the way and then make sure there is no pressure on the opening "stop". This usually involves closing it ever so slightly.

Same here.

Done this way the valve is essentially full open. If a valve check is done there is perceptible movement at the full open stop. If the valve is fully open a decision has to be made as to what the resistance means, full open or closed?

Anyone who can't remember which way to turn the valve should stay away from scuba cylinders. I do realize this is much more difficult when working ones own valves while geared up.

Pete

 

[DandyDon]

Anyone who can't remember which way to turn the valve should stay away from scuba cylinders.

Yeah, there are lots of shoulds in life, including this sport. The incident I witnessed was on the worst boat I've ever been on. I'd already made it politely clear that I did not anyone else setting up my gear, nor anyone but my buddy messing with my tank.

 

[Walter]

Saw this happen to a lady as she descended into the Belize Blue Hole. The second mater checked her tank, which was already open - closed it all the way by mistake, then opened it enough that she had air pressure down to 60 or 80 ft. We had a lot of problems with that mate.

And it didn't matter if it started all the way on or on and back off a tad.

Except that if it's all the way closed you'll know it. If it's all the way closed and then turned on part of a turn you may not until you have trouble getting gas or reach back and check...and of course many divers can't reach their valves.

Nope. You'll know it either way and so would I. You know to watch your SPG as you taqke a breath off your reg. If the pressure drops, it's off. If it drops and rises, it's on, but not enough. If it stays steady, no problem, it might be on all the way or backed off a tad, but you'll have plenty of air. Someone who doesn't watch their SPG won't have a clue either way. I get a good 6 breaths off my reg after I turn off the valve.

Not any more. PADI teaches full open and PADI is the way the world learns to dive.

Well, that certainly convinces me how it should be done. ROTFLMAO!!!!!!!!

 

[DandyDon]

And it didn't matter if it started all the way on or on and back off a tad.

The deck hand had turned it all the way off, then back on 1/4 to 1/2 turn.

 

[bradshsi]

You really haven't lived 'til you've had one stick open so hard that the valve handle fails trying to close it. I've seen that.

The only scenario where not opening the valve full open is an advantage is where you have an equipment failure that requires you to shut the valve while in the water.

The problem in this specific instance, is that if you've been a scuba gorilla and twisted the valve hard open, you may be unable to close it in the water because you can't apply enough force when reaching behind your head.

Personally I open my valve all the way and then close it very slightly. I also don't let other people play with it after I've opened it.

 

[Walter]

The deck hand had turned it all the way off, then back on 1/4 to 1/2 turn.

And he would have done that regardless of how he found it when he started.