Anyone experienced with either Azimuth or Dolphin; advice appreciated

[Pawel]

There have been multiple deaths on scrs and more than one close call by divers that have gone hypoxic.. There are probably many more SCR deaths tha CCR deaths.

Its VERY easy to overbreath an SCR.. ...The KISS is very difficult to overbreath

Greetings padiscubapro,

Sorry, I didn't explain myself clearly (not the first time). What I mean "overbreathe" is kill the scrubber, not decrease O2 content by metabolising down to hypoxic level. This was my concern about Sport KISS. The scrubber is uninsulated, convoluted and gas path is long. The risk of scrubber breakthrough in cold water under heavy exercise is significant, in my view. And, it is a higher risk in a CCR than SCR because CCR scrubber has to "work harder" as all gas is recirculated. There is little you can do when you break through the scrubber. I managed to kill a scrubber once in cold water during heavy exercise. You can flush as much as you want, but the problem comes back almost immediately. You have to bail out.

What you mentioned I call a bad technique and should never be a problem in any well calibrated and operated SCR or CCR. In a SCR, during increased exertion rate (and specially close to surface) you simply press bypass from time to time. Specially so if running on low content mix, like 32%. I have never done any agency's SCR training (even though somehow I am factory qualified to train people on some SCRs :death2: ), but I would imagine that this is normally explained during the first lesson.

Cheers,

Pawel

 

[caveseeker7]

Overbreathing generally refers to an increased breathing rate that will turn the loop content toxic.
As increased breathing translates into higher O2 consumption and hence higher CO2 production the two toxieties relevant are hypoxia and hypercapnia, respectively.

The former is caused by "overbreathing the loop" or "overbreathing the unit" as O2 can be added in various ways, manually, electronically, pure, diluted etc.

The latter is caused by "overbreathing the scrubber".

 

[jptrealty]

Both diverdave and caveseeker (to mention a few) have given you sound advice. I have a dragger it hasn’t seen water in 5 years to be honest I’m not sure were it is. The unit in my opinion is junk. I have over 100 dives on the dragger several to just over 200fsw. I have never been on the OMG products but after having inspected the unit I am unimpressed with the quality of construction, especially having been built by such a well-funded company. There are several issues such as hose connections that are inexcusable.


Here are a couple of additional things to consider:

1) An scr significantly increases the inherent risk of diving without substantial benefit, in addition a strong argument could be made that a scr in more dangerous than ccr. If you can’t manipulate and monitor what your breathing at ALL times there is the potential for disaster its that simple. There are simply to many potential problems with scr designs. I built an scr (it was an imitation rb80) very similar to the German designs that caveseeker7 mentioned, and while its clearly superior to the dragger I have never taken the unit out of my pool (that’s because it doesn’t have the finishes I feel comfortable with, its VERY home built, it would probably kill me). The KISS on the other hand is a fine unit, its VERY well engineered, for those people that still criticize electronics and water; it’s the best solution there is. I think for what you want in a rebreather it’s a great choice.
2) Something I haven’t heard much about when it comes to all rebreathers is slightly more theoretical……..POTENTIAL POINTS OF FALURE. As we all know with every O-ring connection there is the possibility of failure (flood or burst). At what point does having the ability to pipe in additional gas, add sensors, ect. Becomes a liability??? This is something I can’t answer, its something you’ll have to decide for yourself. If you won’t be diving below 100fsw, having an “expedition” level rebreather would be dangerous, it’s to complicated, and therefore it would increase the likelihood of diver error.

I’m not aware of a single instance were there is evidence that would suggest that a CCR rebreather killed someone. This is VERY debatable when it comes to SCR rebreathers. There are to many people that think the progression in rebreather diving is to go to SCR then CCR. This just isn’t so, no matter what rebreather design you go with you are starting over from scratch. The benefits of a CCR unit are clear and numerous, in my opinion there are enough pro’s to justify the switch considering the diving I enjoy.

Another issue is cost, my advise would be to wait and save. If several thousand dollars is a deciding factor, save your money create a rebrsetaher fund and wait till money isn’t an issue. Then buy the product that best suits your needs once. I have spent 10’s of thousands on dive gear that I don’t use or hate. The point being do something right the first time, its much cheaper in the long run

Good luck

 

[Pawel]

...I have never been on the OMG products but after having inspected the unit I am unimpressed with the quality of construction, especially having been built by such a well-funded company. There are several issues such as hose connections that are inexcusable.

What is "inexcusable" about hose connectors?
Quality of what you are unimpressed with?
To my experience OMG products by far exceed quality, reliability and engineering innovation of most, if not all, other competitors.

The KISS on the other hand is a fine unit, its VERY well engineered, for those people that still criticize electronics and water; it’s the best solution there is.

What is "VERY well engineered" in Sport KISS? For me "Sport KISS" is the cheapest and most compromised rebreather that Proletariat can use these days. I would not use it myself for safety reasons (severely compromised scrubber performance, poor inspection and pre-dive check ability, etc.... ). The PPO2 meter is one of the most agricultural and user unfrendly creations I have seen. How many people flooded or broken one? I am also hearing numerous reliability problems with the loop leaking water despite positive/negative pressure checks. Being myself associated with OMG I may be biosed in my opinions but, c'mon, there are many fine units out there: Evolution, Ourborus (sp?), Prism seems like a nice rig...but "Sport KISS"? That's a little bit far fetched, mate.

Pawel

 

[Life-Is-Good-Diver]

What is "inexcusable" about hose connectors?
Quality of what you are unimpressed with?
To my experience OMG products by far exceed quality, reliability and engineering innovation of most, if not all, other competitors.


What is "VERY well engineered" in Sport KISS? For me "Sport KISS" is the cheapest and most compromised rebreather that Proletariat can use these days. I would not use it myself for safety reasons (severely compromised scrubber performance, poor inspection and pre-dive check ability, etc.... ). The PPO2 meter is one of the most agricultural and user unfrendly creations I have seen. How many people flooded or broken one? I am also hearing numerous reliability problems with the loop leaking water despite positive/negative pressure checks. Being myself associated with OMG I may be biosed in my opinions but, c'mon, there are many fine units out there: Evolution, Ourborus (sp?), Prism seems like a nice rig...but "Sport KISS"? That's a little bit far fetched, mate.

Pawel

Hmm, i was considering getting a Sport Kiss myself here, just looking , not made up my mind at all, but considering it.

I wasn't aware of all those problems you mentioned, any thread's or link's , id love to read them.

Thank's !!

 

[KISS57]

What is "inexcusable" about hose connectors?
Quality of what you are unimpressed with?
To my experience OMG products by far exceed quality, reliability and engineering innovation of most, if not all, other competitors.


What is "VERY well engineered" in Sport KISS? For me "Sport KISS" is the cheapest and most compromised rebreather that Proletariat can use these days. I would not use it myself for safety reasons (severely compromised scrubber performance, poor inspection and pre-dive check ability, etc.... ). The PPO2 meter is one of the most agricultural and user unfrendly creations I have seen. How many people flooded or broken one? I am also hearing numerous reliability problems with the loop leaking water despite positive/negative pressure checks. Being myself associated with OMG I may be biosed in my opinions but, c'mon, there are many fine units out there: Evolution, Ourborus (sp?), Prism seems like a nice rig...but "Sport KISS"? That's a little bit far fetched, mate.

Pawel

There is no more certain thing than if you dont like it Pawel then it must be good. Will you ever give up your bagging of the KISS rebreathers? Does it bother you that no one agrees with you?

 

[caveseeker7]

The pO2 displays have already been replaced. Don't know where the inspection/pre-dive problems come from, first I've heard of it. Neither what "severly compromised scrubber performance" is supposed to mean. From what I understand the coaxial scrubber has less time to complete exhaustion than other designs once the sorb is used up. Jetsam states that in their literature, and it's the main reason for the conservative duration and depth rating.

In all fairness, I've reviewed data on the Steam Machines and a Dräger, covering three different scrubber designs: Annular-axial, radial and axial. Once the absorbing capacity goes, it goes fast. The time/CO2-content curve gets very steep (i.e. they time from 0% to 0.5% is longer than from 0.5% to 1% which is longet than from 1% to 1.5% etc).

 

[Pawel]

There is no more certain thing than if you dont like it Pawel then it must be good. Will you ever give up your bagging of the KISS rebreathers? Does it bother you that no one agrees with you?

I have my opinions about Sport KISS and I have supported them. You seem to have a personal problem with me. I am not the subject here.
Pawel
OMG/Apollo Australia

 

[KISS57]

I have my opinions about Sport KISS and I have supported them. You seem to have a personal problem with me. I am not the subject here.

Pawel
OMG/Apollo Australia

You havent supported a thing. You harp on about imadgined problems with the KISS. None of which are true. .

 

[SubMariner]

People, this discussion is getting a bit nasty.

Personal insults are NOT tolerated here on SB, and the offending posts have been edited accordingly.

Your co-operation in this matter is greatly appreciated.

We now return you to your regularly scheduled discussion, already in progress.