Valve Drill- When to do it?

[GDI]

I was asked when is it best to do a complete valve drill during a dive?

Fair enough question. Here is my thoughta and I look forward to reading yours.

During the set up of my equipment I verify my valves position while the tanks are still resting on the rack. As I prepare to don my equipment, that is slide into it, I always open the valves completely. In fact the valves are the first place my hands go to before I don the equipment. (The second spot is the SPG to verify the amount of breathing gas.)

By doing so I never get near the water without my valves turned open, A trip down the wet Orange Grove Stairs proved this to be a wise practise and habit one day as I slipped and slide right into the water only to surface with the fins on my feet, mask on my face and breathing my regs, laughing and thinking that part of the S-drill is now complete - wet breath regs.

As part of my S-Drill I verify the ability to reach the valves but I do not close and re-open them. At the end of the dive this is where I do a full shut down and re-open procedure.

So other then the valve confirmation at the donning of my gear and the reach check as part of my S-Drill I leave the valve drill until just before resurfacing at the dives end. My logic which has been proven correct time and again suggest that too many times divers do a vlave drill at the start of the dive and discover for some reason that they made the dive with partly or worst yet, fully closed valves.

When do you do the valve drill?

 

[texdiveguy]

Your description would fit pretty much my routine also, though I do not do a complete valve drill each and every dive.

 

[RiverRat]

Good info. I'm part way through Adv. Nitrox / Deco and will remember this as I've got all of these skill dives coming up soon. Still tweaking / fiddling with my rig right now and getting used to doubles.

 

[limeyx]

Your description would fit pretty much my routine also, though I do not do a complete valve drill each and every dive.

Same here. A "modified valve" on the surface (make sure valves are on) before I analyze the gas (just in case)

Then on the surface
- Modified valve (which just means making sure all 3 are open, no closing of valves)
- Modified S (can I deploy long hose)
- Breath both regs in water.

For classes, we have been asked to do a Valve/S (full) every time we jump in the water, before the dive, but that's mostly for muscle-memory/practice and to calm down any "nerves" before evaluation dives So far, we always surface, discuss the drills and then do a modified valve before diving, but I think it can also be common to just proceed with the dive.

Hopefully if you do a full Valve drill, your buddies are really watching you, and watching the (mandatory) flow check after the valve drill, so you shouldn't be diving with closed valves.

Also, with the full S-drill, your buddies are making sure your hoses and light cords are stowed properly and not flapping around or snagged.

Of course, some of these things are "easier said than done" as proved within our class!

 

[piikki]

I am maybe a little bit of a tech wannabe, so may I participate? I have never entered water valves closed. I open valve/s before donning, and verify them just before I turn my back to the rig and pull it on. Just before that I verify my buddy’s valves are on too because I’d hate to rush for help with doubles on my back

Then I march towards water, and few meters before I can fall onto my face in wet stuff I put a reg into my mouth and breathe once more. I don’t verify valves by touching them but I breathe both regs in water as I check the SPG again. Then we breathe each others primaries and confirm that hoses are ok by buffing our chests to each others. Then a quick bubble check and off.

I have just started diving doubles, so I pretty much do a valve drill every dive, sometimes twice. Usually it’s done after safety stop is finished, at safety stop depth. If twice, then most of the time right before return or ascent from the target site. If at good depth, we usually pick an obvious visual reference point, so no stupidity ensues as we are learning.

We have not dived HID lights this far but it’s time to start learning. I just read somewhere the GUE sequence with all the light signaling during valve drills. I showed it to my buddy. We both agreed that if the other one forgets that valve drill is going on after the original signaling (and needs several repeat signals during the process), we will need to smack&swap buddies. When I am doing a valve drill, whenever it happens, I expect buddy’s undivided attention. I find the drill fairly easy - hardest part for me is clipping the primary - but I sure would not want to end up messing it up without noticing.

 

[Meng_Tze]

When I set up gear I open valves and verify gas pressure. Then don and in the water do a s-drill and bubble check. When I swim towards the point of entry I do a mod. valve drill to a: make sure I can reach, and b: double check that valves are fully open. I do this with both OC and CC

 

[do it easy]

I am maybe a little bit of a tech wannabe, so may I participate? I have never entered water valves closed. I open valve/s before donning, and verify them just before I turn my back to the rig and pull it on. Just before that I verify my buddy’s valves are on too because I’d hate to rush for help with doubles on my back

Then I march towards water, and few meters before I can fall onto my face in wet stuff I put a reg into my mouth and breathe once more. I don’t verify valves by touching them but I breathe both regs in water as I check the SPG again. Then we breathe each others primaries and confirm that hoses are ok by buffing our chests to each others. Then a quick bubble check and off.

I have just started diving doubles, so I pretty much do a valve drill every dive, sometimes twice. Usually it’s done after safety stop is finished, at safety stop depth. If twice, then most of the time right before return or ascent from the target site. If at good depth, we usually pick an obvious visual reference point, so no stupidity ensues as we are learning.

We have not dived HID lights this far but it’s time to start learning. I just read somewhere the GUE sequence with all the light signaling during valve drills. I showed it to my buddy. We both agreed that if the other one forgets that valve drill is going on after the original signaling (and needs several repeat signals during the process), we will need to smack&swap buddies. When I am doing a valve drill, whenever it happens, I expect buddy’s undivided attention. I find the drill fairly easy - hardest part for me is clipping the primary - but I sure would not want to end up messing it up without noticing.

Looking at the SPG while breathing doesn't tell you much with doubles on, besides your starting pressure.

Assuming you have a hog setup...
If both your tanks are open, but your manifold is closed, then your SPG will still behave the same way as if everything was open, or even if your right post and isolator were both closed. If you are already breathing on the regs, then you know that both posts are at least partially open, but nothing about your isolator.

I'm of the school of thought that the only way to verify that your valves are open is to physically touch them.

 

[Capt Jim Wyatt]

When do you do the valve drill?

After I ensure all valves are completely open I put my gear on prior to diving. At the safety stop/deco stop AFTER the dive is over I do a valve shutdown at the stop on each valve to ensure I am limber enough to do them and to stay in practice.

 

[piikki]

Looking at the SPG while breathing doesn't tell you much with doubles on, besides your starting pressure.

Assuming you have a hog setup...
If both your tanks are open, but your manifold is closed, then your SPG will still behave the same way as if everything was open, or even if your right post and isolator were both closed. If you are already breathing on the regs, then you know that both posts are at least partially open, but nothing about your isolator.

I'm of the school of thought that the only way to verify that your valves are open is to physically touch them.

You are of course correct. I don't check SPG to see my valves are on/off. I check it to see if anything has changed since I last checked it on land - if I have lost more than I expect. This even is very lame because most of the time the water is so much colder I have anyway lost 100-200PSI at that point, and can only guesstimate it isn't a leak until bubble check. I was too religious listing what I do.

 

[TSandM]

So other then the valve confirmation at the donning of my gear and the reach check as part of my S-Drill I leave the valve drill until just before resurfacing at the dives end. My logic which has been proven correct time and again suggest that too many times divers do a vlave drill at the start of the dive and discover for some reason that they made the dive with partly or worst yet, fully closed valves.

This is the reason that GUE uses the valve drill first, then S-drill sequence. If you accidentally left something closed (which you shouldn't have, because the last step of a valve drill is the flow check, and your buddy should be watching that to make sure you do it, and to watch that you're turning things in the right direction) then the S-drill will at the very least catch closed posts. Situational awareness should catch a closed isolator, but that won't be until later in the dive.

I check my valves on the surface and do a flow check before getting in the water, or on the way down, but I don't do valve drills every dive. When I do them, they're done at the beginning of the dive, before the S-drills.