Questions on Rebreather Fills

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Clernix

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A friend just went to Dema and bought a rebreather. I have been interested for many years but never pursued it. The thought of photography without the bubbles does intrigue me.

My question is about the fills for the unit. Can you get a standard nitrox fill? What about the scrubber unit?

Is this something you can do and travel to Asia? It just seems like it would limit your DIve OP selection and really drive up the price of your LA.
 
can you elaborate?

There is a lot of information on here about the basics of rebreathers and I think you'll be able to answer your own questions by doing some light reading and then come back here for clarification
 
It all depends on the rebreather you go with. A semi closed rebreather (SCR) is basically a gas extender, that uses a nitrox or trimix gas. There are occasional bubbles, as the counterlungs exhaust excess gas from time to time. A fully closed circuit rebreather (CCR) is basically a NItrox/ trimix mixing machine on your back (or along your side). You have 2 separate gases one is a diluent (Air, Nitrox or Trimix) & the other is Oxygen, to hold a set PPO2 whether done manually or electronically. As for the the scrubber, there are 2 different types of those. There is an axial scrubber, in which the air flows from one end of the scrubber to the other end & a radial scrubber, in which the air enters a center tube & goes to the outside through the scrubber material surrounding the center tube. Some units travel well in carry-on luggage, some do not. As for getting needed supplies,... you would basically need to call ahead to the operator to see if they are rebreather friendly. Different rebreathers use different scrubber materials,... some are pre- packed some you must pack yourself. If the operator has a 100% Oxygen supply, you could always ship the scrubber to them for you to use & be able to dive a CCR,... if they do not have scrubber, themselves. I would suggest also getting a pretty extensive spare parts kit if you are traveling a great distance, as there may not be any repair facilities available.
 
Not really a simple answer to your question, You can use air(21%) or Nitrox(31%). For diluent, so getting fills at most shops should not be a problem. Higher po2 can be risky as they bring higher risk of spiking if you descend faster than you can metabolize the o2 in your loop, and the higher po2 diluent can make it harder to bring the loop po2 down with a dil flush. I have personally used a 31/32% diluent for shallower dives, but you have to descend slowly and ALWAYS know your po2. *re Electronially controller ECCR

Some Semi closed circuit rebreathers are set up great for using Nitrox, but not ideal for deeper dives.

Re: scrubber medium. I have not traveled to Asia yet, but know it is not uncommon for rebreather divers. I know a group who recently went to Truk Lagoon and were diving O2ptimas. My unit can use either granular sorb, or a EAC cartridge, I think the group I mentioned had a few cases of EACs mailed to the destination in advance.

Seems like it is not that hard to find shops who can support rebreather diving. Just call ahead to make sure they have what you need. I think the bigger question is can they rent you dil/o2 tanks that will work with your unit.

I am planning to go with a group of CCR divers when I schedule my first trip to Truk. I think. It makes more sense to be able to have a pool for spares and support.
 
Thank you both for your answers. It validates my assumption that while it offers some advantages it creates a lot of obstacles too. I travel to remote areas and this does not sound it would meet my needs.

Between photography and diving I carry enough gear as it is.
 
Most places I've talked to in the last year have said they can accommodate my needs. One place told me they couldn't accommodate my needs because they didn't have pure oxygen. I knew they were PP blending their nitrox tanks and asked them what they were doing for nitrox and they admitted that they just didn't know anything about rebreathers and weren't willing to learn.
 
Thank you both for your answers. It validates my assumption that while it offers some advantages it creates a lot of obstacles too. I travel to remote areas and this does not sound it would meet my needs.

Between photography and diving I carry enough gear as it is.
What is remote?
I travel remotely and couldn't do the dives I want on open circuit. Depending on the circumstances rebreathers are actually easier to manage remotely - at least when you are bringing all your owns fills and fill stations along.
 

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