The Tank Valve Feathering/Modulation Technique

[crosshairs]

To recap on an Uncontrolled/Unfixable Free-Flow:
Shut your tank valve down. When you need to take a breath, crack open the tank valve and shut it down again. Repeat as needed, switch to your back-up reg/octopus as well if the unregulated flow of gas from the malfunctioning primary reg is too much to handle. Perform this tank valve "feathering/modulation" technique while doing a CESA (if your buddy is nowhere to be seen and you're essentially solo). . .With your left hand, slow your CESA rate via BCD/wing hose deflator dump button . . .with your right hand reach back, feather/modulate your tank valve and take breaths as needed.

All it takes is practice (and IMHO --should be a mandatory skill taught in basic open water courses. . .)

This is comedy gold right here....

 

[scubadada]

Like I said, too bad it wasn't taught even back then. (Never implied that LA County taught the technique; the context was in relation to "ditch n' don") which isn't taught anymore in any of the commercial agencies --not sure if LA County teaches it anymore either.

Unfortunately, the LA County Underwater Unit no longer offers the Basic Skin and Scuba Diving course. They do offer Rocks, Rips, and Reefs (3Rs). the Advanced Diver Program (ADP) and the Underwater Instructor Certification Course (UICC). http://www.lacscuba.com/

I lived in CA only until finishing medical school in Los Angeles in 1980. If I would have stayed in SoCal, I would have tried very hard to participate in the the very demanding ADP. As opposed to the frequent discussions on SB concerning contemporary AOW training, few would argue that completing the LACUU ADP would not qualify one as an advanced diver.

2014 is the 60th anniversary of the LACUU. Many don't know the organization predates NAUI by a good 5-6 years after being modeled after the Scripps Institution of Oceanography certification program that started a couple of years earlier.

 

[kafkaland]

If I may chime in as a new OW diver... I have tried reaching back to the valve in the pool, and for me it was a bit of a contortion, but possible. I did not try feathering the valve. It seems seems like something I would not intuitively try to do if I had a free-flow at 60ft., with all the bubbles and maybe a tinge of anxiety, just to conserve some air. Breathing from a free-flowing reg, on the other hand was easy. So I'm pretty sure that, should I be in that situation, would be to grab my buddy if he's within easy reach, otherwise go for the surface expeditiously, but in a controlled manner. Even with a free flow, I should have enough air to do that.

On the discussion on what should be taught in OW, or AOW, a skill that I'd really like to learn is how to deploy an SMB from depth. It seems much more useful than this valve-feathering stuff, at least for me. I can easily imagine having to make a blue-water ascent (maybe my navigation isn't up to par yet), and hovering at the safety stop without visual reference isn't easy, either. At this point, my buoyancy skills are ok, but not great. And having my own line from the SMB would help tremendously in that situation, I think. I'm signed up for my AOW class (just waiting for the quarry to warm up a bit before we actually do it), and that's something I'm definitely going to ask the instructor to teach me. So in that way, I'm trying to take AOW as OW part 2 to get more useful skills, not so much as adventure dives to learn fish ID and what have you.

 

[Akimbo]

I was told about “manually regulating flow”, or what you are calling feathering, in my 1962 Scuba class. We didn’t practice it since it is pretty much a no-brainer. This was in the era when double hose regulators dominated and even doubles had just one valve. The recommendation was to remove the tank and hold it in front of you.

The idea of kinking the hose on a single-hose regulator is ill-advised since the most common reason for free-flow is a first stage failure. The possibility of pressure build-up that could cause the hose to blow and make a bad situation worse is too great.

I believe that taking a few minutes to explain the technique in class serves a greater purpose than the technique itself. It causes people to think about what the regulator is really doing and what to do when it fails. My instructor pointed out that Yves le Prieur’s open-circuit Scuba rig used this method and is discussed in Jacques Cousteau’s The Silent World and included a photograph.

 

[MXGratefulDiver]

Bob I didn't realize you are the resident expert on SoCal Channel Island Kelp Diving, all the way from up there in the Pacific NW -just because you did a few trips down here. And if your kit & rig is properly balanced, weighted & trimmed, you will have a snug drysuit on splash-in/descent (inflating just enough to offset suit squeeze) and snug post-dive on the surface --it sounds like you're overweighted from carrying too much spare extra lead for your students Bob.

Unlike you, Kevin, I don't bill myself as a resident expert in anything ... not even things I've done thousands of times and know quite well. That said, I have over 3,000 dives in a drysuit ...and I've not once ever experienced this "shrink wrapping" you talk about on an ascent. The basic physics we teach in Open Water class would suggest that air expands as you ascend, and therefore shrink-wrapping is rather difficult under those circumstances.

And my drysuit exhaust valves -both cuff and shoulder- are on my left arm. It automatically exhausts suit gas at the same time when I raise the hose to dump wing gas. Is yours on the right arm? --perhaps that's your mistaken impression.

... my dump valve's on my left arm too ... but that's not what I was pointing out. What's your right arm doing as you're feathering your valve? Where is it positioned? Isn't it positioned upward, over your right shoulder, allowing you to reach that valve you're talking about? Now ask yourself a simple question, Kevin ... where does air want to go in any air space? What's the highest point on your suit while you're feathering that valve? And, since as you point out, the dump valve's on the left arm, how in hell do you expect that air that's traveling to the highest point ... your right arm ... to escape while you're feathering your valve?

See Kevin ... you're not thinking through what you're talking about before you say it. But maybe physics just works differently for you than it does for the rest of us.

Finally and again, if you have proper gas planning -which I know you teach very well Bob- then why let it run dry on a non fixable free-flow?

Because, Kevin, in the real world, presenting complicated solutions where a simpler one exists doesn't decrease the risk of a bad outcome .. it increases it. Task-loading in a new diver can lead to panic. Panic leads to irrational thoughts and actions that can make people dead when they didn't have to die.

In the real world the priorities are:

1. Don't run out of gas
2. Don't lose your buddy
3. In the event of failure of 1 and 2, get your ass to the surface by the most expedient means.

That means, don't futz around trying to reach your valve, or loosen your waist belt and raise your BCD so that you can. Don't waste time doing a safety stop ... go directly to the surface. Once there, dump your weights, so you can't sink again. Then inflate your BCD, evaluate your circumstances, and take the most expedient action possible to get out of the water.

Simple, direct, and with the highest potential for going home without injury. Gear is replaceable ... bent is fixable ... death is irreversible. You choose which is the priority.

If a novice has the ability and makes the effort to learn the technique effectively as another viable option outside & apart from, or on post-graduation of an agency's formal Scuba training program --well kudos to him/her-- and that's probably gonna be the only way to acquire this skill because of dismissive attitudes (and liabilities) of current Agencies and their Instructors. It's difficult to perform, and even more so in a drysuit, but with practice can be done.

Yeah, because we all know less about dealing with new divers than a guy who's never done it before ...

The difference between a successful person and others is not a lack of strength, not a lack of knowledge, but rather a lack of will.
-Vince Lombardi

Vince Lombardi wasn't a diver ...

... Bob (Grateful Diver)

---------- Post added April 27th, 2014 at 09:32 AM ----------

On the discussion on what should be taught in OW, or AOW, a skill that I'd really like to learn is how to deploy an SMB from depth. It seems much more useful than this valve-feathering stuff, at least for me. I can easily imagine having to make a blue-water ascent (maybe my navigation isn't up to par yet), and hovering at the safety stop without visual reference isn't easy, either. At this point, my buoyancy skills are ok, but not great. And having my own line from the SMB would help tremendously in that situation, I think. I'm signed up for my AOW class (just waiting for the quarry to warm up a bit before we actually do it), and that's something I'm definitely going to ask the instructor to teach me. So in that way, I'm trying to take AOW as OW part 2 to get more useful skills, not so much as adventure dives to learn fish ID and what have you.

SMB deployment is a skill I teach at the AOW level ... for just the reasons you describe. Out here where I dive, current is often an issue, and SMB deployment is a very useful skill once divers start diving on charter boats.

... Bob (Grateful Diver)

 

[lv2dive]

Kevin, you aren't a mirror for anything. You are quite simply smoke.

As to "choosing" to be unmotivated by your chiding...
a) that makes no sense - how does one "choose to be unmotivated"?
b) why do you assume I would even need to be motivated? I never said I wasn't capable of feathering a valve. I said it wasn't a basic OW skill. I'm not a basic OW diver. Get off your high horse and quit making assumptions.

I'm simply a mirror in this instance . . .it's not my problem if you don't like what you see. (Or choose to be unmotivated by a little chiding).

 

[scubadada]

OK, most of us are not going to use Kevin's feathering of our tank valve wihile dealling with a free flowing 2nd stage on a recreational dive. Most of us agree that connecting with one's buddy or direct access to the surface is the best solution. There you go.

Good diving, Craig

 

[Kevrumbo]

Unlike you, Kevin, I don't bill myself as a resident expert in anything ... not even things I've done thousands of times and know quite well. That said, I have over 3,000 dives in a drysuit ...and I've not once ever experienced this "shrink wrapping" you talk about on an ascent. The basic physics we teach in Open Water class would suggest that air expands as you ascend, and therefore shrink-wrapping is rather difficult under those circumstances.


... my dump valve's on my left arm too ... but that's not what I was pointing out. What's your right arm doing as you're feathering your valve? Where is it positioned? Isn't it positioned upward, over your right shoulder, allowing you to reach that valve you're talking about? Now ask yourself a simple question, Kevin ... where does air want to go in any air space? What's the highest point on your suit while you're feathering that valve? And, since as you point out, the dump valve's on the left arm, how in hell do you expect that air that's traveling to the highest point ... your right arm ... to escape while you're feathering your valve?

See Kevin ... you're not thinking through what you're talking about before you say it. But maybe physics just works differently for you than it does for the rest of us.


Because, Kevin, in the real world, presenting complicated solutions where a simpler one exists doesn't decrease the risk of a bad outcome .. it increases it. Task-loading in a new diver can lead to panic. Panic leads to irrational thoughts and actions that can make people dead when they didn't have to die.

In the real world the priorities are:

1. Don't run out of gas
2. Don't lose your buddy
3. In the event of failure of 1 and 2, get your ass to the surface by the most expedient means.

That means, don't futz around trying to reach your valve, or loosen your waist belt and raise your BCD so that you can. Don't waste time doing a safety stop ... go directly to the surface. Once there, dump your weights, so you can't sink again. Then inflate your BCD, evaluate your circumstances, and take the most expedient action possible to get out of the water.

Simple, direct, and with the highest potential for going home without injury. Gear is replaceable ... bent is fixable ... death is irreversible. You choose which is the priority.


Yeah, because we all know less about dealing with new divers than a guy who's never done it before ...



Vince Lombardi wasn't a diver ...

... Bob (Grateful Diver)

---------- Post added April 27th, 2014 at 09:32 AM ----------


SMB deployment is a skill I teach at the AOW level ... for just the reasons you describe. Out here where I dive, current is often an issue, and SMB deployment is a very useful skill once divers start diving on charter boats.

... Bob (Grateful Diver)

Bob, I'm fully vertical when suit & wing gas dumping and doing the valve feathering. The highest point is my left arm on the wing hose dump button. Go ahead now and simply touch back between your shoulder blades with your right arm, and lift your left arm straight up --is that too hard for you to comprehend or perform?

1). Never waste gas if you can feather it.
2). Ibid.
3). Ditto

Kevin, you aren't a mirror for anything. You are quite simply smoke.

As to "choosing" to be unmotivated by your chiding...
a) that makes no sense - how does one "choose to be unmotivated"?
b) why do you assume I would even need to be motivated? I never said I wasn't capable of feathering a valve. I said it wasn't a basic OW skill. I'm not a basic OW diver. Get off your high horse and quit making assumptions.

Is that all you can think about or contribute Kate? Some seemingly personal semantic slight? Can you be motivated to think more objectively?

Jerome Bruner (1983: In Search of Mind) described creativity as "figuring out how to use what you already know in order to go beyond what you currently think."

 

[lv2dive]

Kevin, I was replying to a post you directed AT me. After I made several very objective (and unobjectionable) posts. It's clear nothing is to be gained from continuing to respond to you.

...
Is that all you can think about or contribute Kate? Some seemingly personal semantic slight? Can you be motivated to think more objectively?

 

[scubadada]

Hi Kevin,

Your argument is clearly untenable. Most would have abandoned the debate by now, but you persist.

Best, Craig