Do you dive with your pony valve turned on? Off?

[lowviz]

Off, charged, and forgotten. UNTIL the first time I get 'antsy' about anything. Then on and left on.

 

[dumpsterDiver]

When I started using a pony, I used it in the 'charged but off' mode, primarily because that is what I was told I would do in tech training. I practiced quite a bit with gas switches (backgas to pony, and back again). From tech training onward, I continued the practice with deco cylinders. I teach that method, as well. Before this thread I was not familiar with the slide check aka Shut-off Valve, but now I want to get one to evaluate the device.

I've seen one of those in-line valves explode on the boat. No damage but a lot of noise and loss of gas.

For a single pony/stage bottle configuration, I don't think I would use one. We DID have one on the end of a 25 ft hose which was attached to an oxygen bottle on the boat. It was great for that because it totally prevented free flows etc. when not being used. In that application it seemed worth the added complexity and potential failure; for a simple pony bottle, maybe not?

If you use an inline shut off for a stage bottle, are you supposed to add an over pressure relief valve to the first stage as well? If you got IP creep with the valve off, will the hose be over pressurized?

I don't have any tech training, so I am curious what the expert technical dive instructors say about this stuff?

 

[drbill]

Off, but I do open the valve periodically to ensure the hose and second stage are charged

 

[C Dub]

Thanks for al the great replies, I really appreciate it. I should add I dive a DIR harness, and clip the pony off to my left chest and hip D rings. I can see the 1st, 2nd, and valve quite well.

 

[Dr. Lecter]

Eureka "If it fails you loose the gas completely?"

If the hose fails I lose the gas too, at least until I shut the valve. For what I do - lots of bottles, fairly large deco obligations, long DPV runs - the check valves are the lesser of two evils. YMMV.

Now, people who buy cheap ones rather than Omni Swivel...eh, whatever you want. An OPV on the first stage is definitely best practice.

 

[KevinNM]

I run my pony on, but the reg is right under my chin, so I think I'll notice major issues. If I need the pony reg something really bad has happened and I don't want to screw with anything else under stress.

As to cutoff on the first stage, I know that add helium requires them on stage/deco bottles for classes, I would assume there a reason involving something bad happening to someone to make them insist on this.

 

[kwinter]

I think what Dr. Lecter is failing to mention is that a bailout configuration is different than a pony bottle. We have hoses with QDs to be able to plug in the gas in addition to a hose with second stage. Therefore the second stage could be isolated with the shutoff in case of a free flow while still being able to use the gas through the QD. In a pony bottle situation there is probably only one hose and one second stage. A slide shutoff is not really needed because anything that makes that single hose or second stage unusable kills the use of the tank. So closing the tank valve accomplishes the same thing.

And to repeat again since some people don't seem to read all the posts: yes, if you use a shutoff on the second stage you should add an OPV to the first stage in case of IP creep.


iPhone. iTypo. iApologize.

 

[Bob DBF]

I've seen one of those in-line valves explode on the boat. No damage but a lot of noise and loss of gas.

For a single pony/stage bottle configuration, I don't think I would use one. We DID have one on the end of a 25 ft hose which was attached to an oxygen bottle on the boat. It was great for that because it totally prevented free flows etc. when not being used. In that application it seemed worth the added complexity and potential failure; for a simple pony bottle, maybe not?

If you use an inline shut off for a stage bottle, are you supposed to add an over pressure relief valve to the first stage as well? If you got IP creep with the valve off, will the hose be over pressurized?

I don't have any tech training, so I am curious what the expert technical dive instructors say about this stuff?

Back in the day, I learned the over pressure relief trick after a hose blew at depth on an upstream second. The over pressure relief goes on the first stage or, in my case of my main reg, use a downstream reg as the safe second and it will be the relief.

I leave the valve open on my pony because I use a Sherwood with a dry bleed. If my diving needed the valve off, I guess I'd use a different reg.



Bob
------------------------------------
I think that advocating unsafe and dangerous practices is both stupid and foolish. That is why I don't tell people to do what I do. Dsix36

 

[Dr. Lecter]

I think what Dr. Lecter is failing to mention is that a bailout configuration is different than a pony bottle. We have hoses with QDs to be able to plug in the gas in addition to a hose with second stage. Therefore the second stage could be isolated with the shutoff in case of a free flow while still being able to use the gas through the QD. In a pony bottle situation there is probably only one hose and one second stage. A slide shutoff is not really needed because anything that makes that single hose or second stage unusable kills the use of the tank. So closing the tank valve accomplishes the same thing.

And to repeat again since some people don't seem to read all the posts: yes, if you use a shutoff on the second stage you should add an OPV to the first stage in case of IP creep.


iPhone. iTypo. iApologize.

Not every BO reg has a QD hose, and there are advantages to having a shutoff even for a pony if you're scootering. Otherwise my only real reason for using them is that I don't keep separate OC regs for BO and the occasional pony use. If you're not a CCR diver or a DPV diver, yeah, not so much with needing the slide-check.

 

[Kharon]

Definitely on. If things go to crap I don't want to do more than pull the reg from the octo holder and breathe. Freeflow is obvious because it's on the front of my right shoulder. Knowing that I don't have to fiddle with a valve is calming and is one less thing I have to think about. Lower task loading is good. In an emergency it's great.