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

[Marie13]

One DM on my local (Great Lakes) boat, who is also a tech diver, started off his briefing a few months back by saying something along the lines of that tech divers have a "don't touch my sh*t" attitude and so we won't touch yours unless you ask for help.

A regular buddy did his OW cert under older-school PADI instructors, who taught the quarter turn back thing. I told him if he wants to do that on his tanks, whatever, but don't touch mine unless I ask.

 

[RogueClimber]

Lefty loosey righty tighty is easy when you can see the valve. I’m thinking of when you can’t. Like underwater.

I use the right hand rule: Point your thumb in the direction you want the valve (Handle/Stem/plug and seat assembly) to move. Then curl your fingers. The direction your fingers point as curled is the direction the handle needs to move when turned. You must use the right hand, but it works no matter your orientation to the valve.

Of course this also assumes a standard threading on the valve (or screw or bolt etc) and that you understand you want to move the plug and seat assembly out of the valve body.

Works when you can't see the valve or when you look at it from a different perspective.

 

[aviator8]

The problem is that you can check your valve and pre breathe it, but then you move to the stern and you must pass by the helpful and stealthy dm who often slips a hand in and checks the valve without knowledge or consent of the diver. So I see no full proof solution regardless of full on or slightly backed off open position.

This is a real issue. I know dive ops are trying to be safe when they do this. Maybe some on here that run dive operations can weigh in and say if this is something they require their DM's to do. Frankly the only way I know around this is once you are seated and complete your checks. When you are up there is usually one for not more walking to the platform with you. Walk with your hand on your valve, and leave it there until you are in the water.

 

[johndiver999]

When walking on a pitching boat, you will want to use both of your hands to steady yourself and when wearing dive gear it is almost essential.

 

[tursiops]

I use the right hand rule: Point your thumb in the direction you want the valve (Handle/Stem/plug and seat assembly) to move. Then curl your fingers. The direction your fingers point as curled is the direction the handle needs to move when turned. You must use the right hand, but it works no matter your orientation to the valve.

This is both unclear and anbiguous, and misses the point, which is which way to turn it? That is, which way should the thumb point?

 

[JackD342]

Took me a minute to understand. He is describing two different hand positions using the same rotation, rather than different rotations.
Yes, if you are familiar enough with the valve to understand you are moving the seat in or out, you probably don't have trouble remembering which way to turn.

 

[aviator8]

When walking on a pitching boat, you will want to use both of your hands to steady yourself and when wearing dive gear it is almost essential.

I agree, I was just pointing out that the only real way to make sure nobody messes with it during the shuffle would be to hold it. Not good practice though. Rather than an unknown person behind you making a unilateral decision about what to do with your tank, without your knowledge, and without any physical repercussions to them if they are wrong is not the best approach. I can control what i do, and I can do my buddy checks but if someone sneaks in behind me they can totally screw up my carefully checked preparations. Rather than ops doing this, if they feel the need to be a third check, maybe they could check and if things are not as they think they should be they vocally tell you rather than just changing something. Then you can sort out if it is on or off and have 2 people agree. It is just bad practice to have someone silently doing things to other peoples gear right before going in the water. I agree totally with the all the way on, or all the way off, that's what I do, but I think that DM's and operators need to make changes and be part of the fix too. Either don't do it, or tell people up front what you do, and don't change anything without the divers consent.

 

[EFX]

This is both unclear and anbiguous, and misses the point, which is which way to turn it? That is, which way should the thumb point?

With the valve handle closest to you and looking directly at it a CW rotation closes the valve and a CCW rotation opens the valve. Pretty straight foward if you ask me. Most things that turn or screw on/off have a right-handed thread. One notable difference is the oxy-acetylene torch; The oxygen hose nut and torch connection has left-handed threads to prevent you from switching the two hoses on the torch and blowing yourself up.

On a somewhat related topic why don't tank valves on left side (looking away) manifolded doubles have left-hand threads? If they did, they wouldn't roll off if accidentally rubbed against an overhead ceiling -- they would roll on just like the right side tank valves.

 

[JackD342]

With the valve handle closest to you and looking directly at it a CW rotation closes the valve and a CCW rotation opens the valve. Pretty straight foward if you ask me. Most things that turn or screw on/off have a right-handed thread. One notable difference is the oxy-acetylene torch; The oxygen hose nut and torch connection has left-handed threads to prevent you from switching the two hoses on the torch and blowing yourself up.

On a somewhat related topic why don't tank valves on left side (looking away) manifolded doubles have left-hand threads? If they did, they wouldn't roll off if accidentally rubbed against an overhead ceiling -- they would roll on just like the right side tank valves.

Probably because it would also require a second version of valve seats and of bonnet nuts to be produced as a low percentage subset of already low volume items. It is more than just the valve body threads.

 

[RogueClimber]

This is both unclear and anbiguous, and misses the point, which is which way to turn it? That is, which way should the thumb point?

I did state point the thumb in the direction you want the valve stem/handle/knob to move. It is a simple way to determine which direction to apply force when you are lying upside down, or looking at the valve (or screw, or nut, or bolt) from an other than head on orientation. So to open a valve you would point the thumb away from the valve body, and to close the valve you would point the thumb towards the valve body.