Not being a rebreather diver let alone an instructor, I Googled it to see. The first place I saw teaching the PADI rebreather class is Add Helium. The PADI classes there limit you to diving within NDLs to a maximum depth of 100 feet. The class takes four days.
PADI Rebreather and Advanced Rebreather Course | Add Helium
That's for Rebreather Diver and Advanced Rebreather Diver. Think "Recreational Rebreather" and apply Open Water and Advanced Open Water like standards. Out of curiosity, I took both courses on a Hollis Explorer as part of the roll-out group. Honestly, I think the Hollis Explorer is way more complicated than the Prism 2, but that's another thread for another day. Anyway those are recreational courses designed for guys who go buy an Explorer or a MKVI and want to cruise the reef taking pics of things. BTW - Thanks for reminding me about those courses, because I forgot I was certified on the Explorer!
What we're talking about, or at least what I'm talking about is essentially a Technical Rebreather, using standard technical diving courses as commonly applied.
There are essentially three courses to achieve 100-Meters. PADI Tec 40, Tec 60 and Tec 100, or IANTD Mod 1, Mod 2, and Mod 3, or TDI (which is harder to understand) so here's a link.
https://www.tdisdi.com/tdi/get-certified/tdi-diver-level-courses/ You'll kinda need the standards in front of you to explain it, but same difference, you can take Air Diluient Deco, Mixed Gas CCR, and Advanced Gas CCR and you're there. Some folks will elect the Helitrox CCR with good reasons behind it. I'm a fan of Tx21/35 as dil versus air, but again, another thread another day.
I'm not sure where in any of the courses you'll be prepared for a silty cave or a challenging overhead - they're soft overhead courses by definition, that's why I took NSS-CDS CCR Cave Diver with Jill.
What skills are you really worried about someone with a CCR having that are different at 300ft versus 130? If you know the theory, you know how to plan. If you know how to plan, you know your bailout strategy. Something goes awry - bailout! What's the big mystery we're trying to solve with additional training? By my count, using the three class strategy the student will have at least 30 - 45 hours on the rig being used for training, will have been evaluated by an instructor for over 1000 minutes of Run Time, and if the instructor feels like more soak time is required, that's how it goes. You don't get the card just for showing up at any CCR class I've attended.
All that established - I think the WAY the information is delivered is problematic for new CCR divers and that's the core problem. We need to teach the new divers a different way to think. Ask any long-time CCR diver and you'll see an emerging trend. You'll see a diver who has distilled the thousands of pages of information into, "I need something breathable". I have reduced all the possible failures in my mind into four categories. My bailout strategy for each of those is to bailout and evaluate if I need to perform a gas shutdown (i.e. runway solenoid). That covers CCR emergencies pretty completely. What you do next is where experience, judgment and additional training, i.e. CCR Cave Diver might start to impact if you're going to stay bailed out or not.
I suspect when we evaluate partial failure modes, and/or limping a rebreather into the water or limping it home is where CCR Divers get in trouble. I think the average happy-go-lucky new CCR diver does very well managing in a single failure. But compound failures, which usually begin with a CCR entering the water improperly assembled, or even worse turned off tend to oversaturate the diver, or they misapply the threat matrix, or whatever. Why people limp a rebreather back to the surface in a soft overhead is beyond my comprehension. Not wanting to refill the deco gas is not a vaild reason - even if the visual sticker is three years old and you'll have to dump the tank to get it filled back (been there myself).
If you're not 100% sure what you're about to breathe returning to the loop, stay off of it. Cave could be another thing altogether and additional considerations may open a conversation about edge cases, plumbing in deco gas, SCR modes, and other possible options - this I admit, but for the confines of this conversation, I feel pretty good with bailout using your plan, or follow your computers to the surface.
As a technical diver you need a circuit breaker and maybe a bit of a sixth sense. If a couple things are going wrong, pop that circuit breaker. If it's just not right on a particular day, for no particular reason, but you know it - you have to be willing to call the dive. You can't let the amount you spent on equipment and a good ribbing from the OC guys drag you beyond the limits of reason and safety.
Truth is that the PADI Tec Trimix course taught me absolutely nothing about silt, challenging conditions or anything of the sort. I learned that fills in my doubles are expensive, and how to make an OC Trimix dive. If you want to deal with tight spaces, navigation, silt and darkness, I suggest trying Cave Diver. That's the right class, the class has the right protocols and standards. I took Full Cave both Open and Closed - well worth the money and time invested. You'll never convince me CCR isn't the right tool for Cave. Want proof? Get lost or turned around in a cave on OC and we'll talk.
