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Hey guys, my name is Josh, I'm 16 and work at GUDC.  I'm hoping to start doin' some rebreather training within the next year or so.  Starting off with an intro to rebreather, then move into more of the training and stuff later on towards summer/fall of '07.

  I know there is endless information about rebreathers, and wanted to know what everyone thought about starting this young, possible dangers involved, and any experiences you guys could share that could tell me more about the infamous rebreather. 

  As far as types of rebreathers I have been looking into, I've mostly been interested in semi-closed units, because I am frankly a little scared of using O2, and I like the thought of using basically mixes of 32-60% nitrox instead.  Such semi-closed units I've been interested in are the KISS and the Drager Dolphin.  But, I lean more towards the Dolphin because of the price, especially at my age.

  Now, I admitt that I know very little about rebreathers, and since I am just starting with 'em...could you guys give me some insite?



Thanks guys (or girls)

Josh at GUDC

Welcome to the truly silent world. Josh, I dive a dolphin. I love it below 30". Above that buoyancy is a B__ch. not to mention chubby cheeks. I like it for several reasons. Already mentioned is the quiet. The gas is warmer. and I dont have to change tanks as often. The scrubber is good for 3 hours and that is about how long a tank lasts.
As to which unit, if you are thinking Tech in the future go with the KISS. which is a CCR with SCR capabilities. The Dolphin cannot be used with Tri-Mix in its current configuration. However there are people that have done it. With succes. They are much smarter and daring than I.

Well, for SCR or CCR you certainly work at the right place!  Although they sure know OC as well.

You're young, so join the Navy and have them pay for your training and rebreather...  ;D

For starters, and cost considerations, the Dolphin SCR is an excellent choice.  I wish I never sold mine!  There is a depth limitation to it, though, so if you plan on diving deeper than recreational limits (below 132 ft. - and that's where most of the good wrecks are...) you might want to consider another rebreather.

I have very little experience with the KISS (a manual CCR), but I do know you need to keep track of your PO2 (partial pressure of oxygen) and manually add 02.  So in my opinion, if you can 'handle' the 02 on the KISS, you can 'handle' it on an eCCR (Inspriation, Meg and others that use electronics to control 02 injection).

As with open circuit, the real danger of rebreathers is user stupidity.  I've remembered what Shek Exley said: "Complacency Kills" (or something to that effect).  Do not take it for granted.  A rebreather takes training, discipline, and a bit of distrust.  If something feels wrong, it probably is... so take evasive action!

If you research rebreather deaths, you commonly find:

(1) Oxygen cell(s) are bad.  Yeah, they cost a lot, but if can afford a rebreather, you better be able to afford cells.

(2) Service your equipment.  Don't expect it to remain in tip-top shape year in, day out.

(3) Plan adequate bailout.  Yes, rebreathers can fail - and whether or not it's user error, well, it really doesn't matter when it happens.  A good instructor will explain the best way to plan for bailout - or you can ask questions here!

(4) All rebreathers utilize a CO2 'eating' scrubber.  That's the beauty of SCR/CCR - to reclaim/reuse 02!  But over packing or over exceeding the duration of the scrubber can cause major problems!  Like with the O2 cells, scrubber is cheap - don't try to extend the recommend duration of the scrubber.  Over packing can cause channeling that allows CO2 to pass through - and too much CO2 can cause you to pass out.  Not what you want to do    at any depth.

Some may think the cost of the oxygen cells and scrubber is too much of an expense - but man, what I save on trimix (I fly an Inspiration Classic) I easily afford the expense.  Double 95s run about $75-90 (or so I've heard) while a 20 c.f. of O2 & Trimix Diluent run about $37 (these costs are shop costs - I don't know what it would cost to do it in your garage).  But I digress...

To make a short story long, the Dolphin is a great start... it's affordable, easy to learn, easy to upkeep.  If purchasing used, make sure you have a service history, number of dives on the unit, ask about any problems (hopefully the owner will be honest), and before you dive an used unit, have it serviced!  I know many people like using Ebay or the like, but for my money (and life), I'd rather buy one new or buy one from someone I trust.




Huh, Huh... 4:20

You hear right on the price of Doubles with Helium.  I paid anywhere from 65 for a set of doubles up to 100 for the really high helium mix I used for the tech trip I went on.

Not to mention having to lug doubles around. The tec trips are much easier using the little bottles of the ccr or scr.
Just a little correction for Mark. Poorly packed scrubber can cause channeling, not over packed.

By the way Mark,  if your sorry you sold your Dolphin, I'll trade it back to you. I have always wanted to try and paint one of those yellow shellbacks pink.

WTDRM
Sorry to correct you but the info that Mark was saying came from an e-mail by Martin Parker(the owner of AP Valves that make the Inspiration)
They have found that overpacking the scrubber make the channeling problem worse.
The e-mail had to do with the probems that keep reaccuring even though they are in the manual and in the class.
If you want a copy P.M. me
Bob

Hey thanks guys, Ill be keeping this in mind.  Yes, the person I would buy it from I feel like I could trust my life with him.  He's an awsome guy.  I'll look more into the Dolphins, and Ill be talking more and more with Ron about them and see what type of training I can do.  As for now, I'm working on my rescue class oct. 7-8 and divemaster later on in oct.  Sometime later this winter I'll see what Ron can offer me. 



Keep throwin' all the rebreather info my way guys, it helps a lot!


Thanks,

Josh at GUDC

Thanks Bob. I guess the Optima is looking better all the time.

WTDRM
I think you missunderstood me.
It isn't that the Inspiration has a lot of on going problems.
The problem is that people keep making the same KNOWN mistakes over again and again.
Like not replacing the cells every 18 months, overpacking the scrubber, not checking the intermediate pressures on the regs. and not getting the scubber head serviced.
All these items are covered in the manual and repeated over and over in the class.
The problem is people get complacent and don't follow the training.
At this point you would be hard pressed to convince me that the Optima is better than the Inspiration.

I've seen both rigs, although I have never USED one.  It looks as though that the Inspiration is more streamlined, and possibly better electronics.  The optima however, apears as though it might have a few less failure points, but basically close to the same design.  This is just from what i've seen.  You tell me...

So far the Rebreathers I have seen are the: Asimuth, Kiss, Dolphin, Ray, Inspiration, Meg., Optima, and I think one other but I can't but a name to it.


Josh at GUDC