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fubari · 13th September 2006, 05:29

Quote: (Originally Posted by Dawktah)

My wife no longer wants to dive in the cold water lakes or quarry.
I am game for drysuit and learning about CCR locally.
We will have to see what is in store for us in the next 18 months.
Once we decide to try to have a child I'll be diving on my own so
may recruit a buddy locally and pursue CCR.

Ahh... that makes perfect sense.

Quote:

So I guess I'll ask a few questions I have here.

Quote:

1. I have improved my SAC significantly over the 27 dives but only CCR will keep me down longer than my wife! Is this a safe practice to be diving CCR while your buddy is diving OC?

It can be. An OC diver can donate their octopus to you for an air-share.
You'll probably want an extra pony bottle or stage to donate air for.
I make it a point to tell OC divers I buddy with to go for my 40cft stage.
These have some things to consider:
New Page 0
Diving with a Inspiration Close Circuit Buddy

Quote:

2. Can you donn a CCR in the water attached to a tether? This is the OC technique I am using now from a 15ft. RIB. I am not sure when I'll be able to afford a larger one 20-25ft. Even then I don't know how easy or difficult it will be to donn a CCR on board and roll in.

I think it would be fairly easy to back-roll from a RIB as you're not that high from the water, though I've never dove from a RIB. I prefer to just giant-stride when I can.
Here is an important logistics point to consider: prebreathing your unit is important to ensure it is working (fatalities have occurred because people jumped in the water with their units turned off, or no oxygen, or bad scrubbers, etc - I tell my OC buddies if I'm going to pass out, I want to do it on the surface, not at depth). One way to use pre-breathing time efficiently is to strap your unit on and start pre-breathing while getting other fiddly bits ready (dry gloves, mask, stages). If you're going to pre-breathe (and you really should pre-breathe), it would be a pain to doff it and then enter the water just to put it back on again. (Did I mention you should pre-breathe?)

Quote:

3. Is the Sonolime (sp?) special for diving or is it (can you use) standard soda lime that is used in Anesthesia?

I've used SpheraSorb (a medical-scrubber) to good effect before. Some people prefer sofnolime, some sodasorb, some like the extendair cartridges (painless to change on a boat); hit the search's advanced tool-bar and ask for "sorb" or "scrubber" - I'd say use "search titles only" vs. entire articles, too. One example:
http://www.rebreatherworld.com/techn...rite-sorb.html

Quote:

4. Is there a CCR that the mouthpiece and HUD is better suited to use with a camera?

I think any CCR with a HUD would be good for a camera (perhaps someone with actual photogaphic skill can address this?).

Quote:

5. Do you need to start with SCR and then go to CCR, or can you just start with CCR?

I went straight into CCR. Think through the kinds of dives you want to do (travel to warm water? quarry dives? wreck dives? extended range?) and go for it. There may be reasons why SCR is a better tool (RB80 for extended cave diving seems like a good fit), but I can't think of very many reasons to choose an SCR over CCR.

Quote:

6. Are the gas cylinders/valves unit specific or are they standard Al diving cylinders? Do the cylinders follow the same annual viz and 5 year hydro req.

They're pretty much normal scuba cylinders (steel or AL); it is a good idea to VIP, clean and hydro them as such. To my knowledge, all commercially available civilian CCR's use standard scuba cylinders. The inspiration I'm using takes 3ltr (about 25cft) steel cylinders (think largish pony bottle).
Some units have a chasis that requires a certain size cylinder, others are more flexible.
Some units require non-standard valve shapes; from the top, most scuba valaves look like an L (valve knob at a right-angle to the output), the inspiration valves look like an I (valve knob is opposite the output) so they can fit properly in the chasis once the regulators are connected.

note: Here is something I was surprised be - my local dive shop doesn't like filling my inspiration's cylinders them because they're made in the UK, hence no DOT stamp, so they get funny about insurance (can't say I blame them). Not a huge deal, I just got into trans-filling sooner than I was planning on.

I'd ask about the availability (and maybe rentability) of extra cylinders, valves, and all that as you start to narrow your choices.

Good luck, and happy research

John G.

13th September 2006, 05:29	#7 (permalink)
fubari New Member Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Mar 2005 Location: Chicago, IL Posts: 113	Re: New to the board Quote: (Originally Posted by Dawktah) My wife no longer wants to dive in the cold water lakes or quarry. I am game for drysuit and learning about CCR locally. We will have to see what is in store for us in the next 18 months. Once we decide to try to have a child I'll be diving on my own so may recruit a buddy locally and pursue CCR. Ahh... that makes perfect sense. Quote: So I guess I'll ask a few questions I have here. Quote: 1. I have improved my SAC significantly over the 27 dives but only CCR will keep me down longer than my wife! Is this a safe practice to be diving CCR while your buddy is diving OC? It can be. An OC diver can donate their octopus to you for an air-share. You'll probably want an extra pony bottle or stage to donate air for. I make it a point to tell OC divers I buddy with to go for my 40cft stage. These have some things to consider: New Page 0 Diving with a Inspiration Close Circuit Buddy Quote: 2. Can you donn a CCR in the water attached to a tether? This is the OC technique I am using now from a 15ft. RIB. I am not sure when I'll be able to afford a larger one 20-25ft. Even then I don't know how easy or difficult it will be to donn a CCR on board and roll in. I think it would be fairly easy to back-roll from a RIB as you're not that high from the water, though I've never dove from a RIB. I prefer to just giant-stride when I can. Here is an important logistics point to consider: prebreathing your unit is important to ensure it is working (fatalities have occurred because people jumped in the water with their units turned off, or no oxygen, or bad scrubbers, etc - I tell my OC buddies if I'm going to pass out, I want to do it on the surface, not at depth). One way to use pre-breathing time efficiently is to strap your unit on and start pre-breathing while getting other fiddly bits ready (dry gloves, mask, stages). If you're going to pre-breathe (and you really should pre-breathe), it would be a pain to doff it and then enter the water just to put it back on again. (Did I mention you should pre-breathe?) Quote: 3. Is the Sonolime (sp?) special for diving or is it (can you use) standard soda lime that is used in Anesthesia? I've used SpheraSorb (a medical-scrubber) to good effect before. Some people prefer sofnolime, some sodasorb, some like the extendair cartridges (painless to change on a boat); hit the search's advanced tool-bar and ask for "sorb" or "scrubber" - I'd say use "search titles only" vs. entire articles, too. One example: http://www.rebreatherworld.com/techn...rite-sorb.html Quote: 4. Is there a CCR that the mouthpiece and HUD is better suited to use with a camera? I think any CCR with a HUD would be good for a camera (perhaps someone with actual photogaphic skill can address this?). Quote: 5. Do you need to start with SCR and then go to CCR, or can you just start with CCR? I went straight into CCR. Think through the kinds of dives you want to do (travel to warm water? quarry dives? wreck dives? extended range?) and go for it. There may be reasons why SCR is a better tool (RB80 for extended cave diving seems like a good fit), but I can't think of very many reasons to choose an SCR over CCR. Quote: 6. Are the gas cylinders/valves unit specific or are they standard Al diving cylinders? Do the cylinders follow the same annual viz and 5 year hydro req. They're pretty much normal scuba cylinders (steel or AL); it is a good idea to VIP, clean and hydro them as such. To my knowledge, all commercially available civilian CCR's use standard scuba cylinders. The inspiration I'm using takes 3ltr (about 25cft) steel cylinders (think largish pony bottle). Some units have a chasis that requires a certain size cylinder, others are more flexible. Some units require non-standard valve shapes; from the top, most scuba valaves look like an L (valve knob at a right-angle to the output), the inspiration valves look like an I (valve knob is opposite the output) so they can fit properly in the chasis once the regulators are connected. note: Here is something I was surprised be - my local dive shop doesn't like filling my inspiration's cylinders them because they're made in the UK, hence no DOT stamp, so they get funny about insurance (can't say I blame them). Not a huge deal, I just got into trans-filling sooner than I was planning on. I'd ask about the availability (and maybe rentability) of extra cylinders, valves, and all that as you start to narrow your choices. Good luck, and happy research John G.
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