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+--- Thread: sanctum (/showthread.php?tid=5424)
sanctum - doug67 - 02-07-2011
Hey I saw Sanctum yesterday and had some questions for the rebreather guys. Can you use a full face mask with comms with a rebreather? And can you buddy breath with one? I called B.S. on both things but maybe I'm wrong? Help.
Re: sanctum - Deep Thought - 02-07-2011
Down in Playa ccr diving the Cenote's and have limited wireless, but will try.
No real reason that you can't integrate a FFM on a rebreather, other than you need to have a good oral nasal pocket that does not pool Co2, and you must have a tight seal. Some FFM that I have used in past relied on a positive pressure, which is not the case in a rebreather (ambient pressure). During the Doty filming, the production company asked the "team" to use FFM, just like the episodes of "Deep Sea Detectives"...but due to the depth and challenges I voted that this would not be a good idea for the filming. There is a Drager full face that some divers choose to integrate with full face and I know at least Megalodon ISC purchased a few of these and sold them as a kit to add to ccr's.
If the second question is about buddy breathing on a ccr, sure anything is possible. It is not taught in any of the courses that I offer...but when it comes straight to the point of survival then anything that works works. When you take the DSV (dive surface valve "mouthpiece") out of the divers mouth, then it must be closed. The most practical position to do this would resemble a vintage double hose with one diver riding "piggy-back" and passing the hose overhead, then back down. It would require oral purging of the mouthpiece to vent the small amount of water that would ingress otherwise.
Perhaps I can offer a rebreather demo at Aquaventure and if divers want to try the buddy breathing technique, I can demonstrate this.
Personally my experience on FFM has not been positive enough to warrant the extra effort required - you don't get anything for free and with a FFM you have drawbacks that to me do not yield a postive.
Cenotes are excellent and the weather is here, wish you were beautiful ...
Time for Cervezas!
Ron
Re: sanctum - maizeperro - 02-16-2011
I saw Sanctum the other day at Eden Prairie in IMAX 3D. $16 per person, it's cheaper during the week. Totally worth it! It was pretty awesome. The 3D was great and huge sound. Very realistic I thought except the attempted buddy breathing with full face masks. But as you will see in the movie, it didn't work. So I guess this makes it still realistic. It's a must see if you ever called yourself a diver. And a great movie to show non divers what it's like and why cave divers take the risk. I also enjoyed the rock climbing aspect as I do some of that as well. Also you cannot wait for the DVD. The 3D IMAX experience is half the movie. GO SEE IT!!!!!!
Re: sanctum - aknelsonone - 02-16-2011
Regarding Sactum I have not seen it.
Speaking about the FFM (full face masks), there is only one or two models really build for Rebreathers. One of them is the Draeger NovaR. The NovaR has some of the required features for RB Ron mentioned. The Draeger works with open circuit regulators well too. I actually dive my Draeger FFM a lot very confi. in colder water.
The Buddy breathing is possible when everyone can keep cool. But hardly with a FFM it just takes too much time to clear a FFM. This is one minor reason a lot of the modern RB mouth pieces are equipped with open circuit regulators. A stage with old fashion regulators is still the best back-up system when diving RB.
Andy