Valve Drills

[mikemikethepike]

OK, I have to Ask.

What is the point in doing valve drills on a single tank with a single first stage? I get why you do valve drills on a twin set with manifolds, but the idea of learning to this skill when you only have one first stage does not make sense. The only rational I can think of is you know how to turn it on if you missed every possible pre-dive check and forgot to turn it on before you entered the water, but I think that may be stretching it. Next I thought maybe that because other some people take DIR-F in twins and some take it in singles, they want to make sure that everyone is doing the same "kind" of skills, but that just seems like a stupid kind I egalitarian. May it is just to present another "distracting" task while maintaining a proper position in the water column.

But I am just guessing and I want to know. Why is this skill taught?

 

[Rainer]

If you dive a single, you should be able to reach and manipulate that valve. As you mentioned, being able to turn it on if you somehow forgot all checks (yes doubtful) is prudent. A surprising number of divers don't seem to be able to do this.

 

[ppo2_diver]

Not only if you forget to turn it on, but if some DM on a boat mistakenly doesn't turn it on or accidentally turns it off thinking they were turning it on.

But it also builds some muscle memory if the single tank diver eventually decides to go to doubles.

 

[b1gcountry]

Like Duane and Rainer said, it is a good thing to be able to reach your valve to be able to turn it on if you need to.

You might reach back on the surface and verify it's on before heading down. You may get to the bottom, and find the reg starts breathing hard, and you only turned it part way on, and didn't notice that at the surface. You may also have contacted some overhead, and want to reach back and verify it didn't damage/turn your valve...or maybe you're James Bond, and you have ninja divers swimming around trying to drown you by closing down your valve. :boxing:

It also establishes your flexibility in your exposure protection. If there's an issue with your suit/UW, it identifies it earlier.

Tom

 

[Gombessa]

I don't know about anyone else, but I find it literally impossible to reach the valve on my single tank rig. If I ever jumped in the water with my tank off, I'd better rely on my legs.

 

[battles2a5]

I agree you should be able to reach, and comfortably manipulate the valve for the reasons mentioned above. You can also manage a freeflow on a single by throttling the valve as you breathe.

 

[Bismark]

I don't know about anyone else, but I find it literally impossible to reach the valve on my single tank rig. If I ever jumped in the water with my tank off, I'd better rely on my legs.

This is a problem. For various reasons cited above I would correct this issue. It might be that your exposure protection or your harness is ill fitted, or your tank is in the wrong location or you have flexibility issues. Not to worry, because each and every one of these issues can be corrected.

As a matter of interest, it is a requirement for a recreational pass in a GUE Fundamentals class that you at least be able to reach this valve. I have watched some students begin by not being able to reach it and then by the end of the course, they could.

 

[Gombessa]

This is a problem. For various reasons cited above I would correct this issue. It might be that your exposure protection or your harness is ill fitted, or your tank is in the wrong location or you have flexibility issues. Not to worry, because each and every one of these issues can be corrected.

As a matter of interest, it is a requirement for a recreational pass in a GUE Fundamentals class that you at least be able to reach this valve. I have watched some students begin by not being able to reach it and then by the end of the course, they could.

Thanks, that's a good point. I was actually told by a former gue instructor not to stress about reaching the valve in singles as it was notoriously difficult compared to doubles. It's been a while since I've dived singles so I haven't had the chance to revisit the issue.

 

[Bismark]

Thanks, that's a good point. I was actually told by a former gue instructor not to stress about reaching the valve in singles as it was notoriously difficult compared to doubles. It's been a while since I've dived singles so I haven't had the chance to revisit the issue.

No doubt that it is much more difficult to touch your valve on a single tank. Most likely your difficulty was a combination of the factors that I mentioned. If you can maintain your buoyancy when you do it, try reaching back with your other hand and pull the bottom of your tank forward. A bit tricky to do this and maintain SA and not lose your buoyancy, but it can help. In the real world, if I jumped off a boat in 100ft of water and "discovered" that my tank valve was turned off and I could therefor not take a breath or inflate my wing to slow my ascent, I would kick like hell and grab the bottom of my tank and reach back..........and be very happy I was diving with a buddy who was watching me on our descent.... Remember, you will only have to crack the valve a little bit to get enough gas to breath and slow your descent. Also assumes that your gear is balanced and you are only negative to the extent of your gas weight.

 

[lamont]

If you dive a single, you should be able to reach and manipulate that valve. As you mentioned, being able to turn it on if you somehow forgot all checks (yes doubtful) is prudent. A surprising number of divers don't seem to be able to do this.

It doesn't take missing all checks.

A valve only cracked open 1/4 of a turn can breathe fine on the surface, fully inflate a wing, etc but gradually stop delivering gas as the diver descends from the surface to 60-100 feet.

That can be caught by a valve check at the surface before descending, but i tend to be a big believer in valve checking as a "holistic" end-to-end process -- immediately before putting gear on, after gearing up, after yelling at the DM for fiddling with your gear, final check before descent and being able to check and manipulate it underwater (and with technical diving adding things like after leaving the daylight zone, and after contact with the overhead, etc).

In technical diving the focus in training is often on shutting down posts to fix escaping gas, which doesn't translate as well to open water. However, in practice the more routine focus of valve manipulation in technical diving is really on making sure valves are simply open, which does translate to open water.