Doing AN/DP with FFM, Realistic?

[amascuba]

In my experience, not even remotely realistic. There was a metric ton of gas sharing, lost mask, gas switches, and gas failures in my class. Wearing a FFM would be a detriment to the experience. Something as simple as losing a mask would also mean that you lost your gas.

 

[Addicted2H2O]

In my experience, not even remotely realistic. There was a metric ton of gas sharing, lost mask, gas switches, and gas failures in my class. Wearing a FFM would be a detriment to the experience. Something as simple as losing a mask would also mean that you lost your gas.

Were these simulated/staged failure and losses? Short of a complete strap failure, it's nearly impossible to lose a ffm. And even given that scenario, any competent ffm diver will have a regular mask on them for backup and would theoretically be proficient at switching between the two. I even go as far as carrying a normal 2nd stage w/ a male QD on it so I can switch to a complete traditional setup and still have an octo/secondary to share if necessary. I haven't migrated to a necklace just yet, so yes I still use an octo. And I'm in the process of putting a QD on my octo for the purpose of being able to share air with another ffm diver if needed. Not saying it's smart to do AN/DP with a ffm, as I had that question, too, but losing a mask isn't something I would consider a dive-ending failure.

 

[JohnnyC]

Were these simulated/staged failure and losses? Short of a complete strap failure, it's nearly impossible to lose a ffm. And even given that scenario, any competent ffm diver will have a regular mask on them for backup and would theoretically be proficient at switching between the two. I even go as far as carrying a normal 2nd stage w/ a male QD on it so I can switch to a complete traditional setup and still have an octo/secondary to share if necessary. I haven't migrated to a necklace just yet, so yes I still use an octo. And I'm in the process of putting a QD on my octo for the purpose of being able to share air with another ffm diver if needed. Not saying it's smart to do AN/DP with a ffm, as I had that question, too, but losing a mask isn't something I would consider a dive-ending failure.

Just out of curiosity, what do you imagine your procedure is going to be with the QD on your octo?

Feel free to list step-by-step.

 

[tbone1004]

@Sh0rtBus lost mask drills are just as useful for something failing, i.e. cracked frame, ripped skirt, broken straps, etc.

 

[Addicted2H2O]

Just out of curiosity, what do you imagine your procedure is going to be with the QD on your octo?

Feel free to list step-by-step.

In an OOA with another ffm diver? As long as they're running a QD on their ffm as well, it would be pretty simple. Pull my octo, disconnect the 2nd stage, and connect the hose to the QD on their ffm. It's not something I've practiced or ever had to do, but theoretically I don't see any reason it wouldn't work. I've switched from my ffm to a regular mask and second that way, although not in an emergency situation. If you see any holes in this plan of action, please feel free to critique and explain.

@Sh0rtBus lost mask drills are just as useful for something failing, i.e. cracked frame, ripped skirt, broken straps, etc.

I agree completely. Just pointing out that none of those incidents would necessarily mean the end of a dive with the proper contingency planning. And in the event a ffm diver didn't carry a spare mask with them, they'd still have a secondary reg and could dive wetface to get to the surface, although they may need a little visual guidance.

 

[JohnnyC]

Well, the most glaring issue is that now you have absolutely nothing to donate to an OOG diver. Not only is he out of gas, but now his only source of gas is now entirely unreachable until you can plug him in. Which may or may not be feasible in a timely manner. You're relying on your ability to, in a potentially high stress situation, remove your octo from wherever it's stowed, disconnect your locked QD (because an unlocked QD shouldn't even be an option), stow your octo again somewhere, disconnect his locked QD, and plug in and lock your QD to his mask. All while he doesn't have anything to breathe at all. And that's all assuming you're in calm water with great viz and you both have your buoyancy dialed in, not dealing with gloves, etc. What if you're bouncing around due to surge? What about current pushing you apart? What if your QD won't latch? What if he's panicking? What if you disconnect and he inhales water? Those are a lot of "what if's" to be dealing with without an available gas source for your buddy to breathe.

You could solve the water ingress on his side by using a DESO-type QD like a QC6, but I wouldn't be surprised if the size and weight caused you both to remove them from your masks almost immediately. BOV's are connected to hoses and the QD's are mid-hose between the bailout bottle side and the BOV side. A male and female QC6 set is about 4 inches long. Imagine that sticking out the side of your mask. Omniswivels are shorter, but they're not DESO, so you don't want to be disconnecting them underwater.

You should never be disconnecting a QD if there's not another source of gas to breathe. You're betting someone else's life on you and your gear being able to execute a plan perfectly, without any sort of backup. The best answer is to donate normally and your buddy goes to a half mask after he has secured gas. It's far safer and much less complicated. Get an Omniswivel locking QD so you can easily separate the mask from your gear on land, but underwater connecting and disconnecting to donate gas in a sporting scenario is a really bad idea. Even more so on a technical dive.

 

[Addicted2H2O]

Well, the most glaring issue is that now you have absolutely nothing to donate to an OOG diver. Not only is he out of gas, but now his only source of gas is now entirely unreachable until you can plug him in. Which may or may not be feasible in a timely manner. You're relying on your ability to, in a potentially high stress situation, remove your octo from wherever it's stowed, disconnect your locked QD (because an unlocked QD shouldn't even be an option), stow your octo again somewhere, disconnect his locked QD, and plug in and lock your QD to his mask. All while he doesn't have anything to breathe at all. And that's all assuming you're in calm water with great viz and you both have your buoyancy dialed in, not dealing with gloves, etc. What if you're bouncing around due to surge? What about current pushing you apart? What if your QD won't latch? What if he's panicking? What if you disconnect and he inhales water? Those are a lot of "what if's" to be dealing with without an available gas source for your buddy to breathe.

You could solve the water ingress on his side by using a DESO-type QD like a QC6, but I wouldn't be surprised if the size and weight caused you both to remove them from your masks almost immediately. BOV's are connected to hoses and the QD's are mid-hose between the bailout bottle side and the BOV side. A male and female QC6 set is about 4 inches long. Imagine that sticking out the side of your mask. Omniswivels are shorter, but they're not DESO, so you don't want to be disconnecting them underwater.

You should never be disconnecting a QD if there's not another source of gas to breathe. You're betting someone else's life on you and your gear being able to execute a plan perfectly, without any sort of backup. The best answer is to donate normally and your buddy goes to a half mask after he has secured gas. It's far safer and much less complicated. Get an Omniswivel locking QD so you can easily separate the mask from your gear on land, but underwater connecting and disconnecting to donate gas in a sporting scenario is a really bad idea. Even more so on a technical dive.

I agree with you. And yes the most obvious solution would be to just have the OOA diver remove his/her ffm and take my normal octo 2nd. As long as they have a backup mask to use. Even if they don't, you're right it's probably safer to go that route as opposed to switching out using QD's, etc. But that leaves them then diving wetface and in certain scenarios that might not be best, either. There's risk associated with every situation. Maybe it's something I need to practice in the pool with another ffm diver to see how long it actually takes and how it can be improved upon. Then again in my local lake where vis is marginal at best. With ffm I guess there really is no perfect solution. It's just another piece of gear that could possibly fail during a dive. Which is all the more reason to have and practice contingency plans for those worst case scenario moments. There are obviously divers that complete very technical dives on ffm, so maybe some of the training agencies need to develop tech courses specific to ffm dives and how to handle failure scenarios.

 

[JohnnyC]

Well, I think a wet face is a much lower priority than drowning, but to each their own.

Tbh I don't personally know of anyone doing technical dives with FFM's, all of those that dive with an FFM use a half mask for technical diving, except a few that use FFM for rebreather use, and once they're on bailout at their first gas switch, they're on half mask, if not sooner. If they're on FFM for PSD work, it's to a switch block with the same gas as a reserve. I wouldn't call PSD work technical though, it's somewhere in between.

 

[kensuf]

My opinion is the only place for a FFM in technical diving is either IWR or the oxygen deco on a very long hang. Both cases should involve specific protocols and in-water support.

On the idea of using QD's to plumb into your buddy's FFM, I've seen a number of M&J female QD's that didn't properly mate with some M&J QD males. It seems there are a few male's that were a hair longer than normal, and so the female's won't mate correctly.

The reason this is important is because you can't always be sure you're going to get a QD pair to mate unless you have previously tested it. Finding out they won't mate while you're submerged and trying to do gymnastics with an OOG diver is not a great way to conduct a dive. A friend of mine nearly had a very bad day due to this and it's the main reason we've moved to QC6's.

 

[rjack321]

There are obviously divers that complete very technical dives on ffm, so maybe some of the training agencies need to develop tech courses specific to ffm dives and how to handle failure scenarios.

I have a couple hundred FFM dives (max depth was maybe 22ft in the aquarium here however) so I am following this thread but with little capacity to input.

But this made me curious...
Where are these people and what are they doing? I hate reinventing the wheel so I would look to these procedures - but I am skeptical they exist. At least locally here in the Seattle area we have a bunch of recreational FFM divers and none of them are doing deco dives on a FFM. The PSD and scientific folks using FFMs are prohibited by our OSHA statutes from doing any kind deco. And the commercial divers who are doing deco are not doing any self-initiated in-water gas switches and not using FFMs either (they are using helmets and have a DSO running the switchblock).

So who's doing "very technical" dives like AN/DP on FFMs? Are they in the USA, EU, Asia?