Doing AN/DP with FFM, Realistic?

[rjack321]

Looking at the way @JohnnyC has sort of set you up...

I can imagine an LP hose coming off your FFM going to a splitter with no switch in it.
Splitter terminates in 2 female QC6s
Your bottom gas is plugged into one of the QC6s
The other QC6 female is available to receive gas from your buddies spare QC6

Now you want to switch to your deco gas...
Make sure the deco bottle is pressurized but off
Verify the bottle mix and verify bottle is associated with the QC6 in your hand by bumping the tip and watching the gauge dip.
Plug in the male deco gas QC6 into your free female QC6
Turn on the deco gas the rest of the way
Unplug the backgas QC6
You now have a free female QC6 inlet again in case you go OOG on the deco gas. And you are verifiability off your backgas.

And there's no switchblock knob as part of the verification business.

It does require a buddy with a male QC6 on their backgas and deco bottles. And you still need a normal second stage in case you tear a diaphragm or something like that. And I suspect an OOA situation is still going to be a bit of a CF. But that is a viable no-block verifiable gas switch method above.

Ps you do introduce about a drop of water into the reg 2nd stage from the QC6. All my regs seem to tolerate this into the 2nd stage drop fine. I plug in my BOV with a QC6 salt/fresh doesn't seem to affect it at all. Normal servicing interval seems to be fine

 

[JohnnyC]

The CEJN fittings will allow water ingress. Even the DESO QC6's will allow a drop or so in, but the CEJN fittings are just a threaded hole. If you unplug one underwater, water will flow in, which breaks requirement #2 from the scenario above. A drop that gets blown out is one thing, fully flooding whatever has the male end on it is a different animal.

The locking ring on it is not spring-loaded, it screws open or closed. It isn't great with anything other than bare hands.

 

[Addicted2H2O]

After watching Bryan's video again, it looks to me like for every disconnectable hose, he's using a starndard QD fitting, as upposed to either CEJN or QC6. And I'm a bit surprised to see that he doesn't clip the RSV off to a d-ring and instead just let's it hang at his chest with his necklaced octo. Last thing about his setup is the mask itself. WAY TOO MUCH stuff on it! I'm sure it works well for his purposes, but that would bother me to have that much additional weight around the mask. Seems like it would make it extremely cumbersome. I can maybe see having lights mounted to the sides and obviously the COMS unit, which I'm strongly considering picking up soon. But the addition of the gopro just makes it seems really top heavy and uncomfortable to me. But I digress. The setup itself looks very simple and straight forward; much more so than @tbone1004 descbribed his. Looking at Bryan's it makes sense to have it setup that way. But as I said it looks to me like he's using all standard QD fittings, with two locking ones on the RSV (I use the same ones on my mask and Hog 2nd stage) and then a non-locking one on his mask. So would his kit be acceptable if the fittings were replaced with QC6s?

 

[rjack321]

They look small-ish in the video but at least on his mask that is a CEJN fitting. Those don't have a shutoff on the male side by default (one could in theory be added but you'd have to manually slide them open/shut).

Agree with you his mask has a ton of stuff on it. And his chest is a mess of low hanging necklaces etc

 

[tbone1004]

@Sh0rtBus those are CEJN fittings, likely from Ocean Reef since he's a dealer, but they're definitely CEJN fittings vs. BC connectors. The size is not much different as @rjack321 mentioned.
As far as not having it clipped off, unsure, but there is probably a reason. I would have put a bolt snap about a hands width above the valve on the hose leading to the mask to be able to clip it off, but there is probably a reason he hasn't done that.

Please remember in terms of the stuff on his mask that he's using this for working dives. I.e. murky, nasty, dark. @Lake Hickory Scuba does not only salvage work, but also recoveries of stuff. The lights are required for the environment that he's diving in, and having helmet mounted lights is really not optional for that type of work. The camera helps for the PSD work since it provides documentation of the scene etc. SAV is really helpful when you're sitting in line waiting for your turn and want to be able to breathe and talk freely without removing the mask. Comms for that type of diving go without saying as you mentioned.
Don't personally agree with how long the suicide strap is on the secondary, but the style of routing is one of the least-bad options if you have to share air. Part of the issue with necklace length, especially with the Ocean Reef mask is the exhaust port on the bottom of the mask is quite big and gets in the way of the second stage coming up close. I imagine that was a big consideration for him keeping it that loose. My Poseidon uses a normal second stage, so I don't have that issue, but it's mask specific. Looks like you are using an Ocean Reef as well, so you'll have similar obstacles with secondary routing if you choose to put it on a necklace.

His choice of QD's is perfectly acceptable to me. Like I said above, QC6's are too big and heavy to have on the mask. If you look at the CCR divers that use BOV's, most of them will have a non-locking CEJN connection on the BOV because of how small they are, then use QC6's to plug into the manifold. For his setup, and Bryan please correct me if I'm wrong, but the use of QD's on the block is just for convenience while getting dressed. I.e. put the whole rig on without the RSV, then put the DTV over your neck and plug everything in, then plug the mask in. The advantage for him of keeping everything with the same fitting is when he doesn't have a need for the dual tank valve, you can just plug directly into the mask with the same hose on the first stage. You can see that in some of his other videos where he's only using the primary tank and doesn't have the dual tank valve.

 

[Addicted2H2O]

I understand the significance of everything on his ffm for sure. I like the idea of the lights mounted to the side of the Space Extender frame, rather than the internal visor light that really can't be aimed and could become a serious nuisance to other divers. I think the gopro mounted on the top would bother me. I do have the SAV on mine and wouldn't dive this particular ffm (or any really) without it. I have at times, though, begun my descent and forgotten to close it (oops!). Not a huge ordeal, though, as water really only ingresses in when you inhale and very slowly at that. Sort of bubbles in and you have plenty of time to figure it out, close the SAV and exhale as normal pushing the water out of the exhaust port. The only other modification I've made to mine, aside from the obviously pictured locking QD and omni-style swivel is the addition of the directional exhaust port. It does add a little bit of bulk to the bottom of the mask, which would cause some issues when paired with a secondary necklace for sure. But at this point in time I don't dive that configuration, although I should probably start.

In wrapping this up, as I under the proper assumption that the workable solution for sharing with an OOG diver is utilizing a switch block/RSV and QC6 connectors? I know this has gotten pretty far away from the OP's original question of whether or not to do the AN/DP course using an ffm, but I do feel there's some good, useful information here.

Lastly, I feel maybe I should apologize for my "butthurt" yesterday. I wasn't exactly in the best of moods myself and probably took things a little too personally instead of off the cuff like I should've. I do realize that you guys have FAR more experience than I and I do value each of your suggestions as such. So on that note I offer up a humble "Thanks."

 

[rjack321]

In wrapping this up, as I under the proper assumption that the workable solution for sharing with an OOG diver is utilizing a switch block/RSV and QC6 connectors? I know this has gotten pretty far away from the OP's original question of whether or not to do the AN/DP course using an ffm, but I do feel there's some good, useful information here.

Slight change from my previous post because I forgot about doubles... I would look at the RB80 "switchblock" compared to one of the omniswivel units. Here's why:
The RB80 block looks like this
Switchblock

For you, since you will have doubles on and need access to both sides of the source manifold (L and R posts) I would feed the block with an LP hose from each post on your doubles with screw on LP connections. The QC6 on the left is changed to an LP hose feed out to your FFM. The red and green swagelock ball valves allow you to isolate which of your backgas regs are feeding the FFM so you don't have to ditch your FFmask from a right post failure.

Then you plug in deco gases or in an OOA a donated male QC6 gas to the female QC6 on the bottom as described before.

 

[ffdiver]

Personally, If I were to do this I would go with a MOD 1 mask and change out regs as needed. I wouldn't not use a switch block or QD. It's one thing for bailout but it can get really out of hand very quickly when changing gasses.

I wouldn't have a problem conducting a FFM Deco/AN course but I would absolutely not allow QC6s or switch blocks.

 

[Lake Hickory Scuba]

Sorry that I am late to the party, @tbone1004 just messaged me and asked me to chime in. Full Face Mask Diving, regardless of what type of diving we do, recreational, technical, sidemount, backmount, salvage, fun diving, and even diving in a sewer (which is pretty crappy if I do say so my self) requires a different mind set. When we choose to dive a system that is foreign to us, we will most definitely find that there is a huge learning curve. Philosophies in Scuba Diving tend to be a double edged sword. On one side, they are designed by nature to keep us as safe as possible, so we tend to look at things as failure points (certain types of connectors, etc., etc.), and on the other side, we neglect the reality of the dives that we are making, and what equipment is sufficient for that individual dive.


So lets discuss my setups and the mentality behind them.


[/QUOTE]


This is the current set up I use for Public Safety Diving and Underwater Salvage. I have also been known to use it occasionally for Sidemount Diving on rare occasions. The decision I made is simple. I need a system that works for the type of diving that I do, (In this case, Salvage and Public Safety Work, and 50% of it is solo.) As far as planning goes, in these very specific dives, 20 minutes of bottom time is a thresh-hold that is never exceeded (A standard for Public Safety Work). The items on the mask are very specific in nature and are sufficient for the dives I make. I have to have communications at all times with the surface, hand free lights, and some type of recording device (camera) to protect myself during court room proceedings. When you work alone, it is very easy for an attorney to accuse you of planting evidence on the scene, and the camera is my alibi. The choice to use a gas block system, is strictly personal preference, however, is a great asset in hazmat situations (our local sewers). At the end of the day, I look at my set up as a tool that helps me do a job. I take what I need to do it safely and proficiently.


Tech Diving and Full Face Mask diving is nothing new. As you stated manufactures are making components (gas blocks) that make this possible. They may not be the most popular to mass majority of tech divers, but to some, they are essential. It comes down to what makes the individual diver feel safe, and not so much on the philosophy that has been preached to him/her by his/her instructor. For me personally, I have never really bought into a specific philosophy of gear setup, example being the DIR movement. I do agree with the mentality of it, and respect it, and back in the day before I switched to Sidemount, I followed the DIR way with doubles. But that time has come and gone for me. If I make more than 2 tech dives a year now, it is very rare, so following that philosophy has never really been set in stone for me. Plus, for the last 19 years I have been a Public Servant (you know the type that wear a uniform and badge), and have always been told what to do. When it comes to diving, this is my free time, I do it my way. What ever type of gear you choose to use, I would strongly encourage you to seek out an Instructor or more experienced diver that can mentor you where you need to be. It never hurts to contact the manufacture as well, as they will have the most experience with their system. They will also help you find the model that is the most appropriate for you to use for the type of diving you want to do.

The Ocean Reef that Bryan uses is a bit nicer IMO because it has the locking collar for either position that makes it more obvious to a buddy/tender to see which gas you are on

The locking collar makes switching gas easier, especially in a Sidemount situation, but from the angle I am looking at it underwater (while wearing a Full Face Mask), I hardly ever see it. I constantly have to practice with it, as with thicker gloves, it can be difficult to manipulate underwater. I run drills with the teams I dive with, switching between primary and back up gas. There are times that I don't even bother re-locking the gas block after a switch. In Public Safety work, any change to the dive plan is an immediate abort of the dive. If I ever have to switch to my back up gas (pony), the dive is over no questions asked. I abort and head to the surface. We carry at least 2 if not sometimes 3 cutting devices, and we ditch them upon use. I can't count how many Knives and EMT Shears I have left on the bottom of the lake, after I used them to cut line or string. This type of diving, though structured, is no where near the same as deep technical diving or even cave diving. We only get one shot to do the job or task at hand, after that, we are out of the water, and the next guy goes in. We have a strict dead line (no pun intended) to do the job, as we never inherently risk ourselves for a drowned victim or even for a piece of evidence. Sadly, we have lost several PSD's in the last couple of years, for failing to abide by strict guidelines.

 

[Lake Hickory Scuba]

If you watch the @Lake Hickory Scuba video, you can see on the second stage, there is a non-locking quick disconnect at the mask itself

This is simply because I haven't taken the time to switch it out for the Quick Disconnect from XS Scuba. I prefer it much more so than the one from Ocean Reef. Although I have never had an issue with it coming disconnected, and believe me, I have been in some tight spots before, trying to bag a body, or to collect evidence. One of the biggest reasons I prefer the XS Scuba version, it will fit on any low pressure regulator hose, so I can customize the length. With Ocean Reef, I am restricted to what ever length they offer.