Half Turned Valve

[Packhorse]

This way of testing your valve by looking at your spg while using your reg will not work with an air intergrated comp.
Did you make inquires at the surface to see if the DM turned your valve? I would have, just so they know not to do it.

 

[SparticleBrane]

I'm not a big fan of people touching my gear--this is why.

 

[Splitlip]

Glad it came out OK. The danger is not from turning the valve back half a turn, most of us old timers will never get out of that, now unnecessary, habit. The danger comes from permitting semi-housebroken chimpanzees that suffer from confustion of lateral dominance to touch any of your gear. The first thing that I tell the DMs on a boat is, "Please, do not touch any of my equipment, but feel free to use words, e.g., is your tank valve open?"

You can detect this problem with a quick glance at your spg, it will drop with each breath and then pop back up when the vavle is just cracked open (try it yourself and see).

No need to insult well intentioned crew by refering to them that way.
Besides I have seen many occasions where divers would have splashed with gas off had the crew not opened their valves even AFTER asking if gas was on.
Having said that however, I too would prefer my gear not be touched. But then, I can reach my valves,whereas most divers on charters I see cannot and they are more than happy to have somebody look out for them.

 

[ianr33]

Watching the spg while breathing the regs on the surface will not always catch a partially open valve (depends on just how open it is)

One of the reasons my valves are either all the way on or all the way closed

 

[rigdiver]

Watching the spg while breathing the regs on the surface will not always catch a partially open valve (depends on just how open it is)

One of the reasons my valves are either all the way on or all the way closed

Some have the isolator open just one turn. The rationale is if you have a problem it's only one turn to close. I picked this up from Hal Watts. Makes sense.

 

[SparticleBrane]

most divers on charters I see cannot and they are more than happy to have somebody look out for them.

...If that's the case, do these people need to be diving in the first place?

I don't necessarily mind someone checking to make sure my valve is open while I'm jumping into the ocean on a charter, using a single tank. If the DM is halfway awake he knows which way the valve turns. What gets me is when they CRANK it open...:shakehead :shakehead

However, if I were diving doubles, I'd prefer they don't touch any of my valves, since they probably don't know how they work.

This all only applies to that generic DM on a cattle boat. If I were doing on a dive with only a group of tight diving buddies and we all knew each other's gear, then I wouldn't have an issue with it. Note that I would STILL check my gear in the water, no matter what. You are always responsible for your own gear and your own safety--no one else can be responsible for you.

 

[dannobee]

This way of testing your valve by looking at your spg while using your reg will not work with an air intergrated comp.
Did you make inquires at the surface to see if the DM turned your valve? I would have, just so they know not to do it.

Sure it does. I caught (?) a DM partially turning off my air this way on a dive in Hawaii. Mine's a Pro Plus 2, and the pressure dropped just like an SPG's would, except, of course, the reading was digital, not analog. Same result though. The DM got a stern look from me.

 

[MikeFerrara]

As far as I'm concerned the best practice is to be able to reach your valves.

I start every dive with a modified valve dril...reaching back to make certain that I can reach them and that they are in the correct position.

If someone does fiddle with my valves, no matter because I'll catch it. If I don't catch it and it stops giving me air at depth, I'll reach back and make certain that it's on then.

BTW, the first time I had this happen an instructor turned my air off. I got down a ways and nothing. I tried to reach it and couldn't so I undid the BC cumberbun and hoisted the tank to where I could get at the valve and kept diving. Now, I just make sure that I can get to those valves. Being able to find the valve with the back of your head isn't a pain, it's a comfort.

 

[SparticleBrane]

As usual--well said, Mike.

 

[Walter]

IThe practice of turning a valve a half twist is dangerous as it could have turned out very badly.

Since you don't turn your valve back (why a half twist?) how did that prevent the problem? From your post, it appears it did not. Turning you valve back no more than a quarter turn may have actually prevented the incident. When it didn't move in one direction, the DM probably guessed the valve was closed. Had the valve moved no more than a quarter turn and stopped, he would probably have returned it to it's original position and you would have been unaware he even touched it. Of course, there's no excuse for making it all the way to DM and not knowing the difference between on and off on a tank valve.

I do agree everyone should be able to reach their valves and avoid having anyone touch your gear.