A stupid questions about rebreather training

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jimmy71

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A stupid question. I once met a rebreather diver who did not have his deco or advanced nitrox cert. He told me that shops would only fill his 13cu ft rebreather tank with O2 as he was not certed for anything else. For what ever reason he was in my open circuit advance nitrox/deco procedures class.

How does this normally work? The guy was not the brightest bulb so i declined to ask him any more.

Looking at some online descriptions I gather he had his MOD1. I am unsure why with the supposed hours he had on his unit, that he did not take a MOD 2 course instead of taking the OC adv nitrox/deco.


Looking at training down the road brought up a couple questions.

If you have MOD3 or 4 will a shop accept this to fill your bailout bottles with trimix?

It also seems like that only thing from OC world that will transfer or apply (in the training world) to CCR is the adv nitrox/deco will allow me to skip MOD1 and take MOD 2. Is this correct?

(I know the value of time in water and juggling multiple deco bottles to CCR training, that is not a subject i want to get into here) ALso as i think about this, the reason all of this might have been confusing is that he had a drager dolphin that was converted to a full ccr
I appreciate your help explaining such things.
 
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Definitely scary to think this guy did not go through the requisite steps? Especially with a SCR converted to CCR. BTW - stupid, untrained and diving a RB does not go over well. I know this because some guy did the same thing about a decade ago and ended up dead in the Northeast. So did the guy who 'trained' him.

X
 
I don't have all the answers but I know that my Dolphin cert would let me get 32%, 40%, 50%, and 60% fills in the Drager scr tanks. This would not let me get anything over 40% in any other tanks. Nitrox was required prior to the Dolphin course.
 
He probably only had a dolphin scr card. There isn't really a mod 1 for a scr modified to a ccr. I know that a few instructors offer training on modified dolphins but it isn't from any of the major agencies.
I'm a little surprised he was able to get 100% O2 without advanced nitrox.

Randy
 
So if I have my MOD 3. I should have no problem getting bottles of mixed gas filled for bailout?

Jimmy: there are subtle differences between agencies, but essentially it boils down to the following (and these are TDI standards because that's what I know best...)

First level is Air-Diluent No Deco with a depth limit of 30 metres
(Advanced Nitrox used to be a prerequisite for a CCR/SCR course, but several years ago when we broke up three CCR classes into four by adding this "recreational" level program, we INCLUDED Advanced Nitrox in the topics taught at this level.)

Second level is Air-Diluent with full decompression to 45 metres
(If a candidate comes into a "beginner's class" with OC experience in staged deco, the instructor can "skip" the level one cert and teach to this level right away... there are some provisos but you get the drift.)

Third level is mixed-gas to 60 metres and the fourth is advanced mixed-gas to 100 metres. Prerequisites from level to level includes number of hours on the unit. Hope this helps.


AND ALL LEVELS, a diver is able to purchase the appropriate gases for bailout... for example, a level three graduate would be able to buy an 18/45 trimix in a bailout cylinder with her card... A level one graduate would be able to buy any nitrox up to and including pure oxygen for bailout... and of course pure oxygen and air for her oxygen and diluent bottles respectively
 
thanks for the answers guys. I am trying to plan my diving future and these answers are helping me decide some things. Not counting gas/equipment/sharter fees, What is a reasonable range that should someone expect to pay for mod 2/3/4? (I believe with my prior certs and dives that I probably will not be taking MOD 1)
 
My training was through TDI for MOD 1&2. I had taken adv nitrox and deco before the class. I paid $1500 which is pretty standard for the starting out CCR diver. Since I already had deco procedures Mod 1 and 2 were both included in the class. Now for Mod 3 I paid 1,000 and that was through IANTD. This allowed for Normoxic trimix down to 200ft. I have not taken Mod 4 yet but is in the future for me. Just something to think about, even though I am only Normoxic certified I fill my dil with 10/50. Which is Hypoxic trimix. This is because at 200ft you are breathing approximately 21/35 (with 10/50 dill) which is Normoxic trimix. You will still fill your bailouts with Normoxic blend but not your dill.

Yes that makes for a fun time getting your dil filled the first couple times if you use the same shop.
 
Bob, thanks a ton for the post. That really helps me out. Now to try and figure out which unit will suit me best. I have had trouble finding a large enough try dive center to try multiple units. I did a approx 30 min dive with a evolution on a try dive but would like to try many other units before investing a large chunk of money. Just not sure how to accomplish this...............
 
Bob, thanks a ton for the post. That really helps me out. Now to try and figure out which unit will suit me best. I have had trouble finding a large enough try dive center to try multiple units. I did a approx 30 min dive with a evolution on a try dive but would like to try many other units before investing a large chunk of money. Just not sure how to accomplish this...............

Before you plunk down a lot of money - what will you be using your unit for? Deep, penetration (wreck/cave), silent video work? All units have nuances and some better for specific missions. Modular units where you can mix and match like the Meg, Hammerhead, Revo etc. give you the ability to grow/expand. As you mentioned - it's not easy trying a bunch of them out. I am sure a few folks on here who dive RB's can steer you in some direction with regards to capabilities. The Evo/Insp are definitely decent units. I like them for their ease of breathing and the electronics package has certainly improved over the past ten years. That said - I certainly like other units more than AP's offerings.

X
 
https://www.shearwater.com/products/swift/

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