redundant O2

tibby

Are there a lot of people out there who carry extra O2 sources?...especially cave diving? If so, in what form, 6cf bottle, bailout, staged...? I don't know how to start a poll and I don't think I want one, just asking.
Thanks,
Tibby

__________________
Does the voice of reason change when you add helium to the mix?...hmm

diverreb

I just added a 6 CF O2 Bottle with a BC hose for use as a manual back up. It pops right on the the O2 manual add on the counter lung, if needed.

I already use a 6 CF bottle for suit inflation.... They are mounted on opposite sides of my backplate with the Golem Gear Argon Attachement System For Backplates. I like this system better than the standard SS Quick Links. Keeps the tanks tighter to the rig. I O2 cleaned the inexpensive Argon Regulator that is also available on Golem's site. You can't beat it for $60.00. It's small & light weight. Only downside is no HP ports so you have to check the pressure on the bottle with a pressure gauge.

I moved my light canister (which used to reside where the O2 bottle is now) into my drysuit pocket.

Richie

tibby

That sounds like a very neat arrangement. I would have to find a different place for my light canister though, the 9Ahr Salvo won't fit in my pocket.
Thanks for the reply.
Any other ideas out there?
Tibby

__________________
Does the voice of reason change when you add helium to the mix?...hmm

PacketSniffer

When I get together with my Rebreather cave buddies, we carry a "Rebreather Long Hose" that can connect to a female LP fitting (i.e., to the manual add O2 counterlung hose) to a male LP fitting (i.e., to the manual add LP QD counterlung fitting). We also have, like most Rebreather divers, an extra hose with an LP QD fitting on all bailout cylinders. With this, we can share air utilizing *any* onboard/offboard gas amongst anyone who is in need. It's pretty handy. Coil it up and place it in a dry suit pocket or wherever. It cost about $100 to make and I don't have to carry another cylinder; my buddy has it/them. So, we can share gas just like in open circuit.


Credit should go to Gregg Stanton (Wakulla Diving Center) for that one.

__________________


Far better it is to dare mighty things, to win glorious triumphs, even though checked by failure, than to take rank with those poor spirits who neither enjoy much nor suffer much, because they live in the gray twilight that knows not victory or defeat.

tibby

Wow, never thought of that one, that's pretty cool. So did you add a second LP hose on the O2 side or you rely on the solenoid while sharing O2? I can see how this could work, just have to be careful not to rip the manual add valve off the CL when going through tight spots especially in high flow. Probably easily solved by simply holding on to the hose. A couple of questions if you don't mind:
Do you practice this O2 sharing as a team on a regular basis?
What do you use as a signal to prompt this exercise and avoid confusion such as "out of dil" vs "out of O2"?
I would imagine you bail out first, then start the "plumbing" and then go back on the loop, did I get this right?
Thanks for your reply, very interesting.
Tibby

__________________
Does the voice of reason change when you add helium to the mix?...hmm

tibby

I just realized that my questions may be interpreted as trying to get online dive training which is not my intention, so if these are procedures are covered in some specific CCR course don't hesitate to tell me what that is. Maybe CCR cave...?
Thanks,
Tibby

__________________
Does the voice of reason change when you add helium to the mix?...hmm

dave t

In my ccr trimix courses I teach to plug the sidemount cylinders into the loop manual add buttons, you could run the Rebreather manual on 70 -80% nitrox almost as well as pure o2 if you are deep.
All it needs is a short compatible hose connected to the first stage of each bailout first stage.

practise makes perfect!!

HTH

Dave

Sutty

Wouldn't this be a good argument for having 70-80% heliox rather than nitrox? Then if you have to use it deep to run your rebreather your PN2 doesn't rise.

Neil

__________________
Never forget that life is a finite resource.

dave t

I could run the deep bailout which is tuned to give a decent po2 at depth first in semiclosed and then the shallow bailout (nitrox) in ccr mode when im shallower!
Running the shallow bailout in ccr mode when deep does start to up the n2 content a bit but I would be ascending by then anway and i dont think heliox will offgas you if you have to breathe it OC when shallow

w ripley

I use a Faber steel 12 cf bottle filled with 80% Nitrox, and run my wings and drysuit off of it. Both wings and drysuit use standard quick-disconnect fittings, as do the manual adds on my CLs. Like previous posts, I can connect either hose to either CL manual-add for extended Rebreather use, should for some reason I lose my primary O2.

I run this way to carry more breathable gas into the cave (I can pump the steel bottle higher than I can an aluminum one), to provide a form of backup system should I lose my primary O2, and to separate my wings and drysuit from my diluent system. Both the wings/drysuit system and dil system are separate yet redundant because of the common fittings.

Previous threads have pointed out the danger with plugging in O2 into the O2 manifold while under water, as doing so introduces water into the system running the solenoid, and you don't want anything other than O2 running thru that. It seems to me that the CL is the correct place to "plug" in an O2 source while under water. Obviously if you jump in with the backup O2 already connected this is not an issue.

The bottle hangs on the right arm side of my backplate (clipped to it/weight supported by it) with the web belt running thru a keeper on the lower portion of the bottle. The keeper is simply a web-belt connection like you have on you primary light canister. The primary light canister fits perfectly next to it.

I run the bottle on my "right" side because I've found that I don't notice it there, and it is out of the way of my left side where all of my reels, primary off-board, etc., are kept and worked.

I run a Miflex wing hose straight up my right shoulder, behind my neck, and down the other side on my wing inflator hose. The drysuit hose goes directly from the bottle to the drysuit.

I would run 100% in the bottle but am worried about a static electic discharge within my drysuit (thermals). POOF! I don't know that running 100% within my drysuit would be a problem, but I do know that what I don't know usually hurts me. So for now it's 80%.

I've yet to notice a difference with Argon vs air in my drysuit in cold water in many years of diving cold wrecks, so don't have any trouble with this set up when not in a warmer cave.

Off boards connect to the dil manifold via QC6 QDs.

This system is probably not for everyone, but the more I use it the more it works for me.

Bill