Question Balanced Rigs, Harnesses, and Emergency Scenarios

[TooCold]

It's not an impossible scenario. It makes sense to think about it ahead of time and make a reasoned risk assessment and plan mitigations. It happened to me about 2 years ago. The shoulder inflator attachement separated from the wing. I added air to the drysuit to maintain depth, and as I was faffing around figuring what was wrong the drysuit neck ring tore.

BTW), I suggest putting some weight on a weight belt on your person. This reduces the likelihood you will lose your grip on the rig and rocket to the surface.

I second the recommendation, even if a weightbelt feels like a pita. I'm glad I was.

 

[lowwall]

@lowwall I hadn't considered that my feet were that negative. Interesting. Thanks for bringing that to my attention. I've only been working under the premise that my lungs are just too damn massive. I dive with Jet Fins and since my feet are huge, they're the largest size ScubaPro makes. In total, that might be 7.5 lbs.

It's a lever thing. The further the weight is from the center of balance, the greater the effect it will have.

Let's say you can find some fins that are 2lbs less negative than your Jets. Of course you still need the weight somewhere. But moving that 2 pounds 30 inches up to a pocket on your waist belt or a weight belt has the same effect on your trim as moving 4 pounds from your weight belt 15 inches up to the top tank band.

 

[DiveLikeAMuppet]

I agree that this kind of failure isn't really a thing that's likely to happen. (I'm imagining some freak accident where I've shredded my drysuit and the bladder in my wing.) More than likely, if something like that has occurred, I've also been shredded and won't be able to swim anyway.

I think where this questions stems from is a bit of anxiety around trying to defend my gear selection choice to others who don't have the same experience with this type of configuration. (I'm working on that anxiety, though.)

If it helps, I think you are trying to prepare yourself for a double failure, which is very unlikely. Don’t forget that in the GUE world, you also have well trained teammates who would help you stay afloat and get out.

I would look at the actual risks - sure, your wing or suit might fail but both catastrophically at the same time? If you are worried, invest more into maintenance. You are unlikely to suddenly run out of gas but you could definitely bite off your mouthpiece on the second stage - so you train switching refs. You could suffer from a freeflow or some unfixable first stage failure - but you don’t plan for that to happen to both you and your teammate(s). You generally don’t plan for both of your masks to fail - and worst case your borrow your teammates spare.

When you look at fatalities, outside of rebreathes the #1 cause is medical and fitness related, it’s not faulty kit that is killing people.

 

[Ryan Neely]

If it helps, I think you are trying to prepare yourself for a double failure, which is very unlikely. Don’t forget that in the GUE world, you also have well trained teammates who would help you stay afloat and get out.

Thanks @DiveLikeAMuppet. This perspective helps a lot. You're right, I don't typically train for a double mask failure or a double regulator failure. You're also right that during a typical dive, I do have a well trained team (at least, in the form of my buddy-wife who has been through the same dive training I have).

I think I lost sight of these facts when surrounding myself with students and open water instructors who question my gear. I do tend to have a serious introspective aspect that drives me to reconsider whether I'm "doing it wrong" or whether there is a "better" way. I do realize that "better" is both subjectively and objectively different depending on the person and the situation and the goals of the dive.

This thread has helped me to realize that I'm not afraid of the gear failure (or surviving potential gear failure)--everything everyone has said so far has reminded me of the training and the statistical likelihood of these kinds of failures. I think I was afraid of not being able to explain my choice of gear configuration to those who don't understand it. At the end of the day, that's not my responsibility. This is how I dive and it works for me.

Thanks again for all of your replies. I really appreciate it.

 

[DiveLikeAMuppet]

I think I lost sight of these facts when surrounding myself with students and open water instructors who question my gear.

I think that OWD instructors who don’t dive much outside of teaching students get stuck in the same bubble as high school teachers. They might be really good at teaching yet have no clue how “real” life works because all they know is school and repeatedly teaching beginners - and due to authority gradient, they do feel like gods in their little fiefdom.

It’s actually pretty funny - when you watch some of the OWD training. You see two or three fully kitted divers, overheating in thick neoprene or drysuit, with heavy cylinders on, sometimes even masks on, standing next to water entrance. They rattle to each other in a rapid sequence an explanation of all the strange buckles and dump valves and ditchable weights and retractors on their BE-CE-DEE. Because in an emergency you would totally remember something someone told you one minute before jumping in. Seems to be best practice based on the number of people who do it every weekend at the local quarry - yet none of them do a proper bubble check.

Give me a standard single piece harness and a cutting tool any day .

 

[Subcooled]

This led me to question two things:

1.) In light of the balanced rig concept, just because I could swim the weight I carry to the surface, that doesn't necessarily mean that I would be able to float on the surface with that weight in the event of a total buoyancy failure (drysuit and wing).​

That's why most rigs have shoulder straps. Those can be undone.

2.) Were a total buoyancy failure to happen and I was able to make it to the surface, I'm not certain I would be capable of getting out of my harness to ditch my rig.

I can get out of a 50 pound back pack on dry land. Yours weigh less in water. You do not have firm ground to stand on, that's true, but you are basically pushing the shoulder straps, not planet earth, aren't you?
Maybe this is something you would like to test in a pool?

is a challenge without some kind of counter support​

no, the supporter (planet Earth) only keeps YOU stationary relative to the earth; it does not affect how much force you enact on the shoulder straps. You will sink a bit, of course.

(especially should the harness get caught up on other equipment like dive computers, compasses, or my drysuit exhaust valve).​

That's a minor trouble that you can solve.

given the massive dry glove rings​

I thought it might be enough to fit the palm only...
You might want to try latex on latex instead of these monster designs...

So, here are my questions:​

1.) How do you all handle or prepare for a total buoyancy failure with a heavy rig (be it from weight in pockets or from diving a twinset)?​

I plan for a wing OR a suit failure. A double failure is very very unlikely, especially as I monitor those. Discarding stages can sometimes be a choice.

 

[ChrisMBC]

Something that I don’t feel has been mentioned in this thread is the option (and importance) of practicing oral inflation of the BCD. Especially in a single tank rig, you can plausibly have a double buoyancy failure if you lose your only gas source (for example, tank valve isn’t open on descent). This is solvable while using someone else’s reg, providing that you’re comfortable orally inflating your BCD.

 

[Ryan Neely]

Something that I don’t feel has been mentioned in this thread is the option (and importance) of practicing oral inflation of the BCD. Especially in a single tank rig, you can plausibly have a double buoyancy failure if you lose your only gas source (for example, tank valve isn’t open on descent). This is solvable while using someone else’s reg, providing that you’re comfortable orally inflating your BCD.

Orally inflating the BC is super important. I do practice this regularly*. I guess I had never considered a loss of buoyancy due to an out of gas situation. That's interesting. I think that, for some reason, I've been focused on a double buoyancy failure at the deepest part of the dive, but everyone here so far is right: a double buoyancy failure is going to be exceedingly rare, I have other buoyancy options (like a DSMB), (on the surface) the gear I'm carrying shouldn't be any heavier than a large backpack that I should be able to get out of my rig, and I have a team who can help me all of those thing.

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*I hadn't set out to intentionally practice orally inflating my wing. I had a particularly minor, yet irritating equipment malfunction that led to this.

On my rig there is a large rubber o-ring woven between the webbing and the tri-glide that holds the left chest D-ring. This o-ring is the retainer that holds my low pressure inflator valve against the webbing to keep the inflator from floating around and becoming a flappy snag hazard.

When connecting the low pressure inflator hose to the inflator valve, the quick release collar would often work its way into a position to be directly above this rubber o-ring retainer.

For almost a year, every time I lifted my inflator over my head to descend at the beginning of the dive, the rubber o-ring retainer would roll against the quick release on the inflator hose, popping it off of the inflator valve. I wouldn't know this had happened until I approached the bottom and went to inflate my wing only to find that my descend wasn't slowing.

The first time this happened, I was on vacation in the Caribbean diving in a wet suit. My only option was to orally inflate the wing at depth, inhaling from the regulator and exhaling into the wing. When I was finally neutral, I was able to take a moment to assess the situation and reattach the inflator hose.

Since the only time I ever raise the inflator valve over my head is when I'm descending from the surface, it didn't matter how the inflator hose was connected for the rest of the dive. It worked fine during the dive, but sure enough, on the next dive, it would pop off again.

I have since finally learned how to route the rubber o-ring retainer around the inflator hose to prevent this problem from happening, but thanks to that problem, I am now super proficient at orally inflating my wing.