[Dawktah]

Hello Everyone!

I am new to diving and new to the concept of CCR. I have 27 dives and moving to CCR is something I want to do. Mainly for use to advance my interest in underwater photography. I have a lot to read to decide on which unit to learn. I will almost exclusively be diving in tropical waters. I would be interested in finding CCR divers in the Virgin Islands for training.

I live in Chicago, but haven't done any diving here since my open water certification.

Looking at the smileys, this board is A LOT OF FUN!

--Chris

[RebreatherNut]

Chris,

From one Chicagoan to another, Welcome to Rebreatherworld!

You will find a wealth of information here on Rebreather World and this should help you make a decision of what type of rig you are looking for. But nothing is better than actually beeing able to try it out.

Again, welcome on board!

RBN

[fubari]

Quote: (Originally Posted by Dawktah)

I live in Chicago, but haven't done any diving here since my open water certification.

Welcome aboard, Chris
This is a really good place for learning.

No local diving... No time? Or do you just like warm water better?

John G.

[Jason Ooi]

Welcome to Rebreather World

[DrDiverDave]

Dive, Dive, Dive ...

Welcome to the group. I'm pretty new here myself, but I've been diving and teaching for awhile and love it more the more I dive. I suggest that you dive locally and get really comfortable in a wide variety of conditions while learning about CCR from the group. CCR will help your photography of fish, especially game fish, but there are lots of awsome photo's to take of invertibrates and less skiddish fish, even in local (lower visablity) conditions. There is a lot to learn here, and more diving experience will help you to understand it better, and expand your abilities.

Enjoy diving,

David

[Dawktah]

Quote: (Originally Posted by fubari)

Welcome aboard, Chris
This is a really good place for learning.

No local diving... No time? Or do you just like warm water better?

John G.

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

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?

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.

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

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

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

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.?

More to come...

--Chris

[fubari]

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.

[bendomatic]

Hi

Just to answer your question about diving CCR off a RIB. We have had numerous RBs dive off our RIB. SportsKiss, ClassicKiss, Meg, Inspo, Optima, and converted Azimuth, all without incident on entry. Our RIB is 5.5m gemini, we fit 4 RBs and stages. Most people backroll or side roll. while we gear up in the boat, we "ungear" at the end of the dive in the water and have someone haul it out or clip it off (if you trust a clip!), then swim in with fins on. If there is some current then we advise people to feet first entry with a half turn holding the side rope (do you know what i mean??? like a seated entry that i taught in OW courses) as close to the bow as possible and head straight down the line.

Like mentioned earlier, prebreathing is usually done on the boat, while sitting on the tubes, getting on all the other bits and pieces. I have done a prebreathe before leaving shore for the dive site, but that's only when it's 5-15min boat ride to the site.

rachel

ok the boat is MHDs.

[caveseeker7]

Welcome to Rebreather World, Chris.

Quote: (Originally Posted by Dawktah)

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?

They cheat. I don#t know how, but they cheat.

No problem diving with an OC buddy as long as they know a bit about breathers, what to look for (bubbles mostly) and what not to do. The link to Divemole's website above is a good one, IIRC the current Ambient Pressure manuals also give some info in that regard.

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.

Shouldn't be a problem, you'll doff and don the Rebreather underwater during class.
On the other hand I did side rolls off a RIB with the SportKiss without problems, one of the guys that day dove an Evolution and rolled off, too. The RIB was larger than 15ft, though.

Quote:

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

Yes, there is diving grade Sofnolime (797 I believe) in 8-12 mesh, as well as 4-8 mesh. Also popular, especially in the US, is Sodasorb from Grace in either 6-12 mesh or 4-8 mesh. Dräger manufactures Dive Sorb in 5-9 mesh. IIRC the main difference to medical sorb is the water content for diving applications.

Quote:

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

Mouthpieces and HUDs have been discussed quite a bit. Use the search function for DSV, BOV, HUD and HDD. And have a look in the library.

Personally I've used the former with (BOV) integrated bailout second stage and without (DSV). I very much prefer the BOV.

I also dove RBs with and without HUD and much rather have a HUD than not.

But that's very much a personal preference, as is most everything else about RBs.

Quote:

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

Pretty much the same as above, this subject has been hotly debated. And in the end there is no right or wrong way. Some people who went from SCR to CCR said it was a waste to dive SCR first, others will tell you they gained experience they wouldn't want to miss.

I tried SCR and CCRs with instructors, watching them setting up the RBs and pre-diving them. Tried them out. Watched the post dive. And decided to go straight to CCR.

I highly recommend you have a look around what's on the market and try what you think might work for you. Then find an instructor and do an intro. Nothing like some 1st hand experience with both the unit and the instructor, and it's plenty of fun.

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.?

Most RBs use standard SCUBA tanks, though usually smaller ones than OC. 2 and 3 ltr are most common for CCRs, 4 ltr for SCRs. Viz and hydro are the same. The few models that use non-SCUBA tanks are usually old, military or both. Those tanks can be quite expensive, hard to source, and a pita to deal with as they usually don't have DOT stamping, need X-ray testing etc..

[ScubaDadMiami]

Welcome aboard.