What is "recreational" rebreather, and any recommendations?

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In Europe our instructors tend to die with O2 turned off quite often...
 
Yes, it’s my opinion, thought IMHO covered that.

Bringing guns into this is hyperbolic and unhelpful. Guns are designed to bring lethal force to bear on a target, rebreathers have no such purpose. I disagree with the notion that my rebreather is trying to kill me. If I do everything I’m supposed to, my Prism 1 will keep me alive as long as I am sentient.

I

It's metaphoric more than it is hyperbolic. Guns can kill if you pull the trigger, rebreathers can kill if you don't use them properly.
The point is that you cannot say that rebreather are NOT dangerous, or rather, not NOT say that rebreather are dangerous, without exposing yourself to guilt by omission. In fact recreational OC scuba is, and even this is not emphasized enough, in general. I personally know just as many victims on OC (most recreational) as on CCR.
It is something that a potential CCR diver needs to ponder for him or herself very very carefully. This is not regular scuba diving. It is technical whether dove at recreational depth or not, notwithstanding the claims of any manufacturer or training agency about the contrary. I moved to CCR because I wanted to go technical. With experience, I would say that if I had not had any plans to dive deep and long, the move to CCR would not have been worth it, and in fact, it would have turned into a major drag (I am an amateur videographer and photographer). Plus everything which has already been said about CCR divers flatlining left and right...
It is the internet, and we have no idea what the OP knows or doesn't, what is his level of self-awareness, whether he is just prodding water or has already made his mind, etc.
Yes, the sport can be practiced safely. But lower your guard, and the margin of error is much thinner than on recreational OC. And we all do lower our guard.
 
In Europe our instructors tend to die with O2 turned off quite often...

Interesting, the question then becomes, would this happen so often if the EU allowed sales of MCCRs? I’d bet MCCR divers make this mistake less frequently as they are likely more conscious of O2 delivery than ECCR divers, by design. This also points to the task loading issue, and the need for even greater vigilance on the part of instructors...
 
It's metaphoric more than it is hyperbolic. Guns can kill if you pull the trigger, rebreathers can kill if you don't use them properly.
The point is that you cannot say that rebreather are NOT dangerous, or rather, not NOT say that rebreather are dangerous, without exposing yourself to guilt by omission. In fact recreational OC scuba is, and even this is not emphasized enough, in general. I personally know just as many victims on OC (most recreational) as on CCR.
It is something that a potential CCR diver needs to ponder for him or herself very very carefully. This is not regular scuba diving. It is technical whether dove at recreational depth or not, notwithstanding the claims of any manufacturer or training agency about the contrary. I moved to CCR because I wanted to go technical. With experience, I would say that if I had not had any plans to dive deep and long, the move to CCR would not have been worth it, and in fact, it would have turned into a major drag (I am an amateur videographer and photographer). Plus everything which has already been said about CCR divers flatlining left and right...
It is the internet, and we have no idea what the OP knows or doesn't, what is his level of self-awareness, whether he is just prodding water or has already made his mind, etc.
Yes, the sport can be practiced safely. But lower your guard, and the margin of error is much thinner than on recreational OC. And we all do lower our guard.

Yes, we do not know what the OP knows already, but if he does a casual search on the Internet he will find lots of hits about the dangers of rebreather diving. Danger is a relative term, when I said they are not dangerous, it is implied that they are less dangerous than some activities and more than others. Far more people ride motorcycles on this planet every day than go diving, and motorcycles are far more dangerous and the hazards much more random and beyond operator control. As you said, OC divers die regularly as well, so danger is truly relative. It takes a special kind of person to forget that putting yourself in the most hostile environment on earth is baseline dangerous. The price of freedom is eternal vigilance, I was not trying to counsel that rebreather diving was totally safe, which is definitely something different from “dangerous”. In my mind, given that we are putting ourselves in a hostile environment to begin with, the question becomes are the risks manageable or not? And the follow on question, are the benefits of CCR diving great enough to go through the expense and time of getting certified? This is a question that goes straight to the diver’s motivation, and whether its strong enough to promote a proper respect for what is involved. I personally do not believe that we are doing ourselves or anyone else a service by characterizing CCRs as baseline “dangerous”, given the hostile environment is already dangerous. That was the nature of my opening statement. Let’s all inform those who ask to the degree we are able, and then let them decide what is dangerous.

I have met numerous people who wanted to start riding motorcycles and asked me about my experience with them. I try to answer honestly that I very much enjoyed motorcycles but believed there were too many random hazards to make riding regularly a safe bet. With motorcycles it’s a numbers game, having to do with how much time you spend on your bike. I was putting almost 1000 miles a week on mine the last time I got hit. My standard response is take your bike out on Sundays and enjoy it for a few hours a week if you want to reduce your risk.

CCR diving is almost the opposite, the more time you spend doing it correctly, the greater your experience level and the more likely you are to handle a problem correctly or avoid them in the first place.
 
Well, as the OP I can only say thanks to everyone who weighed in on this. It was very eye-opening for me, and has actually made the answer to my question pretty easy--stay on OC. It seems that a rebreather is not going to offer me a substantial advantage in the recreational diving I do, and will have several very big disadvantages:
1. Constant focus on, concern about, and involvement with the gear during the dive. This is a gigantic disadvantage, and it is the opposite if what I have now, where I have primary focus on and involvement with the dive experience itself, and what I want to do (whether photography or just enjoying the experience). My OC maintenance requirements are minimal, attention to the gear during the dive (except a regular check of gas) is absolutely minimal, my mastery of the gear is pretty much effortless, as is buoyancy control and ability to handle the extremely unlikely failures that might happen.. It does not seem worth it to me to sacrifice this.
2. "Fear of the gear". See above, constant worry about whether some fault in the gear or small omission on my part will injure me or place my buddies in jeopardy. Just not the same with OC, which is farm animal easy and pretty much bulletproof reliable with simple regular maintenance.
3. Disproportionate burden of training/experience to the benefit obtained. If I chose to dive rebreather, I would not settle for less than excellence and mastery over the gear. To do this, I am told here (and I believe you) that I might have to put in 50 to 100 hours of diving before I should seriously consider bringing a camera (or, for that matter, even being relatively relaxed on a dive) For me, this might be two years of diving (at least for the 100 hours). I see no benefit worth giving up two years of photography and relaxation.
4. Extremely high risk compared to OC diving. No further discussion needed here. After a lifetime of safe diving and thousands of dives, do I really want the risk of death that comes with this? And, even more risky because I am a photographer? No, thanks.
5. Cost. Not so huge of a thing (I am an UW photog after all . . .). But, still, for the $15,000 or more cost, I could have multiple bucket list dive experiences, including week-long liveaboards in Indonesia, Galapagos, Red Sea, or doing the Sardine Run, etc. I think these experiences are going to benefit me with memories, challenges and experiences that are worth far more.

In sum, I agree with the notion, stated right at the beginning, that "recreational" rebreather diving is a complete misnomer. I see the benefit of these for long-distance cave explorers, extreme deep tech divers, and similar specialized needs where they might offer some real advantages that outweigh the disadvantages. But for me, the benefits (some extra bottom time, silence and no bubbles) are just not big enough things to offset all of the downsides. I also now understand why I just don't see any rebreather divers doing the diving and photography that I do, and I dive in an area with lots of advanced recreational divers.
 
It is the internet, and we have no idea what the OP knows or doesn't, what is his level of self-awareness, whether he is just prodding water or has already made his mind, etc.

And this is a crucial point, especially WRT the most recent back and forth in this discussion.

These two statements are not mutually exclusive:

1) If you always do everything right, the chance of a rebreather fatality is vanishingly small

2) The chance of any given diver always doing everything right is vanishingly small

Ideally, systems are designed so that any one pilot error doesn't inevitably lead to disaster, and that's a good thing. Training and experience are crucial, and we are right to stress their importance.

I would just be careful about making blanket statements. Especially since for the few people that we know who have died doing this kind of diving, we don't really know what happened.
 
Well, as the OP I can only say thanks to everyone who weighed in on this. It was very eye-opening for me, and has actually made the answer to my question pretty easy--stay on OC. It seems that a rebreather is not going to offer me a substantial advantage in the recreational diving I do, and will have several very big disadvantages:
1. Constant focus on, concern about, and involvement with the gear during the dive. This is a gigantic disadvantage, and it is the opposite if what I have now, where I have primary focus on and involvement with the dive experience itself, and what I want to do (whether photography or just enjoying the experience). My OC maintenance requirements are minimal, attention to the gear during the dive (except a regular check of gas) is absolutely minimal, my mastery of the gear is pretty much effortless, as is buoyancy control and ability to handle the extremely unlikely failures that might happen.. It does not seem worth it to me to sacrifice this.
2. "Fear of the gear". See above, constant worry about whether some fault in the gear or small omission on my part will injure me or place my buddies in jeopardy. Just not the same with OC, which is farm animal easy and pretty much bulletproof reliable with simple regular maintenance.
3. Disproportionate burden of training/experience to the benefit obtained. If I chose to dive rebreather, I would not settle for less than excellence and mastery over the gear. To do this, I am told here (and I believe you) that I might have to put in 50 to 100 hours of diving before I should seriously consider bringing a camera (or, for that matter, even being relatively relaxed on a dive) For me, this might be two years of diving (at least for the 100 hours). I see no benefit worth giving up two years of photography and relaxation.
4. Extremely high risk compared to OC diving. No further discussion needed here. After a lifetime of safe diving and thousands of dives, do I really want the risk of death that comes with this? And, even more risky because I am a photographer? No, thanks.
5. Cost. Not so huge of a thing (I am an UW photog after all . . .). But, still, for the $15,000 or more cost, I could have multiple bucket list dive experiences, including week-long liveaboards in Indonesia, Galapagos, Red Sea, or doing the Sardine Run, etc. I think these experiences are going to benefit me with memories, challenges and experiences that are worth far more.

In sum, I agree with the notion, stated right at the beginning, that "recreational" rebreather diving is a complete misnomer. I see the benefit of these for long-distance cave explorers, extreme deep tech divers, and similar specialized needs where they might offer some real advantages that outweigh the disadvantages. But for me, the benefits (some extra bottom time, silence and no bubbles) are just not big enough things to offset all of the downsides. I also now understand why I just don't see any rebreather divers doing the diving and photography that I do, and I dive in an area with lots of advanced recreational divers.

Thanks for the thoughtful and detailed post, I understand all of the concerns you raised.

I would like to clarify at least a few things from my vantage point as a nature loving CCR diver. When I say maximum diver involvement promotes CCR safety, I mean in the whole dive, not just with my gear. Paying attention to your PO2 and the proper functioning of your CCR does indeed become second nature and involves little more than diving OC at that point. We all have computers and need to check our gas, time and profiles, right? Almost all CCRs have HUDs of some kind so checking your PO2 involves looking at the HUD and looking at the secondary from time to time. Noticing whether a solenoid fires when you ascend is certainly not hard to do while doing something else. In fact, I would point out that the relative silence of CCR diving allows me to enjoy the dive more than on OC because I’m more aware of my environment, not to mention the behavior of the animal life towards the large, silent fish creeping around them. It’s all part of my definition of maximum involvement. And not to be snobby, but I’m not sure how OC divers can fully enjoy a dive with a bunch of OC bubbles and computer ascent alarms going off constantly around them.

I have seen reef sharks and large old turtles on every dive in places like Ambergris Key where they are rarely if ever seen. I have had schools of eagle rays follow me and watched reef sharks hover inches above my head for an hour in between striking fish in the current on a point, totally oblivious to my presence. The picture in my avatar is from the end of one of the best dives I’ve ever had. It was on a seamount in Papua New Guinea, we had a 12 foot sand tiger, an oceanic manta with a 15+’ wingspan, silver tips, hammerheads, silky sharks, several species of whaler shark, and a rhinopias on the anchor line at the end. There were 12 divers in the water, all on CCR, including Gordon and Kim Smith who can be seen in the background of that picture. I seriously doubt that dive would’ve been the same if 12 OC divers were in the water.

I totally understand the cost/time benefit analysis you mentioned given the amount of diving you do every year, but if you do ever find yourself in a situation where you can dive more frequently, I don’t think you would regret making the switch. Also, there are many used units for under 3K, and training can be done at the beginning of a vacation, allowing you to train and get some fun hours in on the unit as well. Bonaire is a great place for CCR training...
 
I totally understand the cost/time benefit analysis you mentioned given the amount of diving you do every year, but if you do ever find yourself in a situation where you can dive more frequently, I don’t think you would regret making the switch. Also, there are many used units for under 3K, and training can be done at the beginning of a vacation, allowing you to train and get some fun hours in on the unit as well. Bonaire is a great place for CCR training...

Yeah, exactly. Of course, no one should feel pushed into CCR diving because they "need" it to get great photos. But the OP also should realistically assess the risks and benefits.

For me, switching to CCR has revitalized my love of diving. I love building it, I love cleaning it, I love talking about rebreathers here on SB. I find it fascinating. And while I'm careful with the gear and the operation of the gear, I don't feel that it has impaired my ability to take photos (I really only dive to do photos and video). I have a NERD, so that goes a long way in putting my PO2 information right in front of me while I'm setting up a shot. I totally enjoy diving here in the NYC area, and I don't feel that the dive is consumed by constantly working the equipment.

If the OP has decided that he doesn't have or want to develop a rebreather pilot's mindset, he shouldn't feel pushed to do so. And if he really wants to be able to do a quick rinse of his gear and forget about it until the next dive, then he shouldn't consider CCR. That's not a failing, that's just being realistic about what he is prepared to do for a hobby.
 
Interesting, the question then becomes, would this happen so often if the EU allowed sales of MCCRs? I’d bet MCCR divers make this mistake less frequently as they are likely more conscious of O2 delivery than ECCR divers, by design. This also points to the task loading issue, and the need for even greater vigilance on the part of instructors...
I'm new to CCR and somehow I do not agree with your statement, are you referring to the design of the diver using eCCR or the unit?
IMO, and as so nicely stated in some manuals, the CCR diver first line of defense is his brain. If you do not turn on the gas supply it means you got complacent and did not follow your checklist / protocol. But that is my opinion and I'll stick to it. Some of my dive buddies are diving CCR for 15 years and still used a reference card prior to every dive, by design an alert diver. Now I am nowhere experienced enough to make a call on the dynamics of a mCCR vs eCCR diver, however logic tells me there should not be any as the function remains the same.
I do appreciate that I was trained to fly my eCCR manual and have not to date relied on the electronics to fly the unit, however during task loading on ascend I have consciously allowed it to do the O2 addition while I'm reeling in a spool etc. but always with a constant mind on my controllers.
 
I'm new to CCR and somehow I do not agree with your statement, are you referring to the design of the diver using eCCR or the unit?
IMO, and as so nicely stated in some manuals, the CCR diver first line of defense is his brain. If you do not turn on the gas supply it means you got complacent and did not follow your checklist / protocol. But that is my opinion and I'll stick to it. Some of my dive buddies are diving CCR for 15 years and still used a reference card prior to every dive, by design an alert diver. Now I am nowhere experienced enough to make a call on the dynamics of a mCCR vs eCCR diver, however logic tells me there should not be any as the function remains the same.
I do appreciate that I was trained to fly my eCCR manual and have not to date relied on the electronics to fly the unit, however during task loading on ascend I have consciously allowed it to do the O2 addition while I'm reeling in a spool etc. but always with a constant mind on my controllers.

It’s good that you trained and continue to run your unit mostly MCCR. However, I think some differences between M and ECCR still do apply. An MCCR diver is not listening for a solenoid, an MCCR diver also knows that their O2 is delivered by a mass flow orifice of some kind and that they will need to inject O2 to supplement their O2 consumption and maintain their target PO2 at various points in the dive, usually when working hard or ascending. This means an MCCR diver is more conscious of their O2 consumption moment to moment, by design and as the dynamics of their dive change.

An ECCR diver who flies their unit fully auto is not as aware of their O2 consumption from moment to moment as an MCCR diver, just as someone driving cruise control on the highway is less aware of the need to increase or decrease the throttle to maintain a target speed.

Don’t get me wrong, I dive an ECCR but it happens to be the simplest one ever made, the Prism 1/Topaz. All it does is maintain SP, which I find useful mainly in high task loading situations during open ocean diving. I too was trained by learning how to dive my unit fully manual first, which really made me conscious of my O2 metabolism and sensor behavior and reaction times.

Check lists are good, but forgetting to turn on your gas is a minor mistake if your valves are on the bottom and can be reached easily. Things happen on boats, people get distracted. But if you understand the workings of your unit and body you will be watching your PO2 and your gauges during crucial phases like descent. Good design facilitates diver awareness and puts them in the middle of all monitoring and functioning of their loop, IMHO. Poor training and divers in a hurry to “master” CCR are the common denominators in many accident reports...
 

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