DIR Rebreather - Thoughts - Page 3

**Howard Payne** · February 3rd, 2007, 01:46 PM

Quote:

far too much ego involved

Therein lies the problem with this whole idea

I put this same arguement to a CCR diver well known on the the UK circuit a while back and he said its badly needed but it aint gonna happen.
As he pointed out - if you turn up to do a deep dive on a CCR boat - everyone will have completely different kit, different gas, different bailout and a different set of protocols and deco "requirements". In spite of the fact that everyone's there to do exactly the same dive.
People derive comfort from thinking they've got it all worked out with all their modifications and idiocyncracies.
In order to make this idea work - people would have to be prepared to give up what are for them "cornerstones" and in some cases adopt kit or practices that may be in their eyes either bestways "different" or worstways "inferior".
You have to give up what gives you "comfort" now to gain a greater "comfort" from standardising training, gases, kit and bailout etc
Can't see it happening myself - too many mavericks - too many big egos

Mark Chase · February 3rd, 2007, 03:09 PM

Quote: (Originally Posted by Howard Payne)

Therein lies the problem with this whole idea

I put this same arguement to a CCR diver well known on the the UK circuit a while back and he said its badly needed but it aint gonna happen.
As he pointed out - if you turn up to do a deep dive on a CCR boat - everyone will have completely different kit, different gas, different bailout and a different set of protocols and deco "requirements". In spite of the fact that everyone's there to do exactly the same dive.
People derive comfort from thinking they've got it all worked out with all their modifications and idiocyncracies.
In order to make this idea work - people would have to be prepared to give up what are for them "cornerstones" and in some cases adopt kit or practices that may be in their eyes either bestways "different" or worstways "inferior".
You have to give up what gives you "comfort" now to gain a greater "comfort" from standardising training, gases, kit and bailout etc
Can't see it happening myself - too many mavericks - too many big egos

And yet some damed fine divers gave up their long established rigs and protocols and decided to go DIR?

I think the above is an accurate description of a typical day boat dive. However there are divers on that boat who I know crave something different. There is Me, Howard (Dude) and Janos for a start.

Possibly your suggesting that I don't have a big ego? That would shock a lot of readers on this forum I am sure

There will be CCR divers who rebel against the idea of DIRebreather I am sure of that but there is a group of CCR divers like me who believe standards and revised training techniques are the way forward for CCR. I would argue it may be more important than for OC and more important than building in nanny sate of the art safety features like C02 monitors into existing units.

I believe existing CCR training standards are inadequate. There are instructors out there putting in the additional information into the training but there are others that are not. I also believe there is a need to improve Mod1 training to include specific cell monitoring drills and that BOVs should be standard on all rigs.

If I have to sell my rig and get a different one to go DIRebreather then so be it. Standard gas lists? no problem, Standard bailout rigs? No problem. Standard skill sets and drills? no problem. Bring it on i think to improve the general safety of CCR diving its desperately needed.

I wish GUE would do it but seeing as they don't i welcome anyone who is willing to pick up the gauntlet.

ATB

Mark Chase

Mark Chase · February 3rd, 2007, 04:18 PM

Quote: (Originally Posted by Alastair)

Well without wanting to revist your ludicrous gas prices a 60m dive costs me about £60 so actually I can afford to do it as often as I have the time to go diving. Time is my limiting factor not money.

Possibly a Darwin award at some point if you tox on PP02 of 2.5 but that's about it

So my decision to what is the safest approach should actually be dictated by money? That's why your CCR diving is not DIR because you are choosing to accept risks based on the wrong reasons.

I'd encourage anyone to dive safely but for most the cost of the RB, maintenance, vr£'s, HUD's, upgrades etc means that the idea they are spending less money is laughable. In your case Mark with your rip-off mix merchant it may well does cost in with your 2nd hand RB etc. But it's a very small section of the dive community who that really applies to. Hell Fraser lives in Kent and he never pays more for gas than I do (might be a team approach creeping in there).

I find ascertions that CCR is the only way to go is a flawed argument.

Cheers
Al

I assume you get the fills for Frazer so this is not a particularly relevant point unless you going to sort out fills for me as well.

I am aware of Kent Diving in Dartford and Dive Machine in Tonbridge wells who do mix fills. There is Lakeside as well but I don't know how much he charges as It wasn't open when I dived OC.

I am also aware you get these incredible prices but I just don't have access to such cheep fills. I simply couldn't do a 70m dive on £60's worth of gas. Even home brew it would cost me more than that.

A twin set of 17/50 costs £101 for Kent Diving, a 7 of 21/35 is about £20 a 10 of 50% is £9.00 and a 10 of 100% is £25.00

So my gas bill from the shop would be £155 + at least two trips back and forth to the dive shop which for me is over 120miles of driving. Home brew from garage fill man I am looking at about £110. He has to cover his compressor running costs, tank rental and make some profit so I don't complain.

However he has gone CCR and will no longer fill twin sets. It was this move that forced me to consider my options and go CCR it was either that or put a limit my annual trimix diving.

So 32 dives = £4960 in gas. + driving costs
Home brew = £3520
For you = £1920
On CCR = £480

That includes gas lime and disposables. And I only need to go to the dive shop once in about every 10 dives to fill my bank tanks.

You have demonstrated in the past that by running twin 12s and keeping the bottom times short, you can do the diving much cheaper than this. However I am not prepared to do less than a 30min bottom time and generally aim for 45mins.

Whilst you believe that CCR is inherently dangerous, I don't share that belief so safety is not the issue here. Analysis of CCR incidents has shown me that basic diver errors and cutting corners on redundancy, were the primary causes of death. These are the very issues I would hope DIRebreather will address.

I have done my best to analise all the available information on CCR fatalities and I haven't been able to pinpoint any death that could be directly attributed to the electronics of the unit. Whilst they can and do fail it appears that in some incidence it has been the diver failing to carry out a successfull bailout that resulted in death. A situation that could be easily avoided with the use of suitable off board bailout gas and a BOV. Sadly in many cases its the failure of the diver to monitor his situation (see my point on the HUD) or to carry out suitable pre and mid dive checks that has resulted in the incident.

If disagree and you have a case history you wish to discuss, I would be pleased to go through it with you.

Whilst your for telling of my demise via a PP02 hit may well come true some day, it wont be for want of trying to avoid it. I do have a wife and kids after all.

When my unit spiked at 2.5 at 68m my HUD informed me of the problem immediately the unit passed 1.6. However the spike grew in seconds. I was able to dill flush quickly so i was probably breathing elevated PP02 for 30-40 seconds.

Since that incident (and because of it) I have fitted a Bail Out Valve. (BOV)If it should occur again ill just turn the valve and go OC which in practice would put me on a safe gas in under four seconds.

I believe most peoples feelings on the CCR issue are based on a lack of understanding of the units. Most anti CCR divers have never had any training to dive one.

Sadly i also beleive present training is not focused enough and needs review.

ATB

Mark Chase

jerry.mobbs · February 3rd, 2007, 04:56 PM

Quote: (Originally Posted by Mark Chase)

When my unit spiked at 2.5 at 68m my HUD informed me of the problem immediately the unit passed 1.6. However the spike grew in seconds. I was able to dill flush quickly so i was probably breathing elevated PP02 for 30-40 seconds.

Mark Chase

any idea why this spike happened?

cheers

jerry

onthetrain · February 3rd, 2007, 05:03 PM

Quote: (Originally Posted by Howard Payne)

Therein lies the problem with this whole idea

I put this same arguement to a CCR diver well known on the the UK circuit a while back and he said its badly needed but it aint gonna happen.
As he pointed out - if you turn up to do a deep dive on a CCR boat - everyone will have completely different kit, different gas, different bailout and a different set of protocols and deco "requirements". In spite of the fact that everyone's there to do exactly the same dive.
People derive comfort from thinking they've got it all worked out with all their modifications and idiocyncracies.
In order to make this idea work - people would have to be prepared to give up what are for them "cornerstones" and in some cases adopt kit or practices that may be in their eyes either bestways "different" or worstways "inferior".
You have to give up what gives you "comfort" now to gain a greater "comfort" from standardising training, gases, kit and bailout etc
Can't see it happening myself - too many mavericks - too many big egos

Howard this is a little bit of a flawed argument mate.

It's a bit like saying all OC divers are DIR! Most are not, because there are too many mavericks, and big ego's etc etc.

The simple fact (for me anyway) is that DIR is not for everyone. Many people do not like the strict team protocols, the kit standardisation etc etc. Those who frequent this forum do.

Its clear that Myself, Chasey, Janos and others find the concept an interesting one. I dont think a DIR CCR system would work for everyone, as it doesnt for all OC divers.

What I am saying is that diving A CCR could be improved for some of us through standardisation.

Alan.

PS Clare thanks for trying to shut down the OC V CCR cost argument. In my view it does not fit with what I am trying to explore here.

Thanks for your views so far folks. Keep them coming

Alan

onthetrain · February 3rd, 2007, 05:05 PM

Quote: (Originally Posted by EBT)

Its not happened, or its not widely discussed on the internet because some people prefer to do, rather than talk

(no, its not me)

Onthetrain, if you're serious; Eau2 Technical diver training, cave diver training, trimix and rebreather courses in UK, Europe and World-wide, dont be put off by the website, use the contact option.

Regards,

/Zak

Zak, will you be at the dive show?

If so maybe we can meet up to discuss the options?

Alan

**Howard Payne** · February 3rd, 2007, 06:08 PM

So get together with Zak, Chasey, Janos, Digger and anyone else who's interested and try and thrash something out that's workable. Strikes me that you've just got to go for it and then a system will evolve from there? Genuinely wish you all the best with it

Mats Edenfeldt · February 3rd, 2007, 08:11 PM

Lets break this down a bit more and lets try to find what you need as a minimal standard for equipment and team. This is how I would approach it.

We already have this, this is absolutely basic.

Use OC if it can be done on OC
Have enough gas to be able to bail out and do the remaining dive on OC
Team awareness, dive in team and use same gas and same equipment

What kind of equipment is usable and what kind of equipment is not in to much violation of the basic DIR principle. As I see it first of all take the electronics out of the picture totally. Po2 monitoring sure (aloast a must when talking about CCR?!?!) but to have the rebreather relying on electronics primary is not OK as I see it. It needs to be simple in the design and simple to use with standard gasses, also the whole team need to have the same kit/configuration.
Also deco on some sort of computer linked to the unit should also be taken out of the picture, so now we have a basic and quit simple machine.

But how about the redundancy and the bail out and the gas management? First of all I would look at the use of a rebreather after 50-55 meters, before that it can be done simple and quit cheap with ordinary DIR kit OC rig. The rebreather as I see it is a bonus, as long as it works it works and the dive can be executed as planned, if it does not work tuff shit go back on OC and abort the dive. To use the rebreather this way i think its easiest to apply the standard gases, the GUE standards is a good base. Then an OC bailout can be done at any time. Should the deco be done on the RB or on OC? I think its more safe to do it on OC + you can use more of the standard deco method. If I am not to far out there a rebreather diver keep the po2 higher during accent and in this way does the deco and this in collaboration wit some sort of on board computer…right!!!?

But here we come back to the core of the problem if you get a rebreather just to make it easier for you it gets lost right here because you still need to have the deco bottles and bottom stages to do the dive. Maybe with the kit below you can use the back mounted tanks for bail out, anything less for a 70 m dive is to little.

A rebreather must be seen as a tool for the job and if its not needed don’t bring it. It can also be seen as a gasmanagement tool and something that makes an expedition easier. The RB80 does this in a great way but a CCR does it better, but the CCR demands more of the diver and the team if you where to use it in a more DIR friendly way.

I would love to do some CCR training just for the fun of it and because I am curious, I will not use it for my kind of diving but just to learn more about the equipment on the other side of the fence.

Mark you say you want to get more of a standard and more of a DIR approach with CCR:s…what is your suggestions and what problems in the above written can you see?

Ahmed Adly, Marlin Inn DC · February 3rd, 2007, 09:02 PM

I don't see anything bad about this configuration. Tell me if I am wrong but it is a KISS CCR rigged like an RB80.
Well, this is what I was always talking about basically which is RB80 style but substituting SCR for CCR.

As long as the team has standard gasses and the back gas is enough to bail out on, I really don't see the problem, except that I still like the idea of continuous F02 (for some reasons).

Mark Chase · February 3rd, 2007, 09:47 PM

Quote: (Originally Posted by jerry.mobbs)

any idea why this spike happened?

cheers

jerry

A problem with the new Aluminum hand sets and SS battery caps.

Aluminum oxide build up on the thread in the hand set causing failure of the circuit under load (ie when the solenoid fires). As the battery's performance drops off (due to dropping temperature at depth and the use of akoline batteries) The controller switches off.

When the solenoid stopped firing the circuit was reestablished and the unit booted up. In doing so it tested the solenoid by firing it for three seconds and injecting a big slug of 02 into the loop which at 68m doesn't take long to spike the PP02.

Firing the solenoid causes it to shut down again and so on.

The problem was solved by using a conductive antioxidant on the battery cap thread.

ATB

Mark Chase

February 3rd, 2007, 01:46 PM	#21 (permalink)
Howard Payne(Offline) The Voices And The Becks Join Date: Nov 2005 Location: London Posts: 1,897	Quote: far too much ego involved Therein lies the problem with this whole idea I put this same arguement to a CCR diver well known on the the UK circuit a while back and he said its badly needed but it aint gonna happen. As he pointed out - if you turn up to do a deep dive on a CCR boat - everyone will have completely different kit, different gas, different bailout and a different set of protocols and deco "requirements". In spite of the fact that everyone's there to do exactly the same dive. People derive comfort from thinking they've got it all worked out with all their modifications and idiocyncracies. In order to make this idea work - people would have to be prepared to give up what are for them "cornerstones" and in some cases adopt kit or practices that may be in their eyes either bestways "different" or worstways "inferior". You have to give up what gives you "comfort" now to gain a greater "comfort" from standardising training, gases, kit and bailout etc Can't see it happening myself - too many mavericks - too many big egos __________________ Eastbourne Sub-Aqua Club 0513 Nitrox & Trimix, Club Boat, Plenty of Good Value Diving, Regular Club Trips & Holidays, Rec & Tech Training, GUE / Hogarthian Friendly Come Try Us!

February 3rd, 2007, 03:09 PM	#22 (permalink)
Mark Chase(Offline) New Member Join Date: Nov 2005 Location: Kent England Posts: 1,069	Quote: (Originally Posted by Howard Payne) Therein lies the problem with this whole idea I put this same arguement to a CCR diver well known on the the UK circuit a while back and he said its badly needed but it aint gonna happen. As he pointed out - if you turn up to do a deep dive on a CCR boat - everyone will have completely different kit, different gas, different bailout and a different set of protocols and deco "requirements". In spite of the fact that everyone's there to do exactly the same dive. People derive comfort from thinking they've got it all worked out with all their modifications and idiocyncracies. In order to make this idea work - people would have to be prepared to give up what are for them "cornerstones" and in some cases adopt kit or practices that may be in their eyes either bestways "different" or worstways "inferior". You have to give up what gives you "comfort" now to gain a greater "comfort" from standardising training, gases, kit and bailout etc Can't see it happening myself - too many mavericks - too many big egos And yet some damed fine divers gave up their long established rigs and protocols and decided to go DIR? I think the above is an accurate description of a typical day boat dive. However there are divers on that boat who I know crave something different. There is Me, Howard (Dude) and Janos for a start. Possibly your suggesting that I don't have a big ego? That would shock a lot of readers on this forum I am sure There will be CCR divers who rebel against the idea of DIRebreather I am sure of that but there is a group of CCR divers like me who believe standards and revised training techniques are the way forward for CCR. I would argue it may be more important than for OC and more important than building in nanny sate of the art safety features like C02 monitors into existing units. I believe existing CCR training standards are inadequate. There are instructors out there putting in the additional information into the training but there are others that are not. I also believe there is a need to improve Mod1 training to include specific cell monitoring drills and that BOVs should be standard on all rigs. If I have to sell my rig and get a different one to go DIRebreather then so be it. Standard gas lists? no problem, Standard bailout rigs? No problem. Standard skill sets and drills? no problem. Bring it on i think to improve the general safety of CCR diving its desperately needed. I wish GUE would do it but seeing as they don't i welcome anyone who is willing to pick up the gauntlet. ATB Mark Chase __________________ The only DIR Inspiration/Hammer head/KISS/rEvo/JJ diver in the village www.ourturkishvilla.co.uk Last edited by Mark Chase; February 3rd, 2007 at 04:34 PM..

February 3rd, 2007, 04:18 PM	#23 (permalink)
Mark Chase(Offline) New Member Join Date: Nov 2005 Location: Kent England Posts: 1,069	Quote: (Originally Posted by Alastair) Well without wanting to revist your ludicrous gas prices a 60m dive costs me about £60 so actually I can afford to do it as often as I have the time to go diving. Time is my limiting factor not money. Possibly a Darwin award at some point if you tox on PP02 of 2.5 but that's about it So my decision to what is the safest approach should actually be dictated by money? That's why your CCR diving is not DIR because you are choosing to accept risks based on the wrong reasons. I'd encourage anyone to dive safely but for most the cost of the RB, maintenance, vr£'s, HUD's, upgrades etc means that the idea they are spending less money is laughable. In your case Mark with your rip-off mix merchant it may well does cost in with your 2nd hand RB etc. But it's a very small section of the dive community who that really applies to. Hell Fraser lives in Kent and he never pays more for gas than I do (might be a team approach creeping in there). I find ascertions that CCR is the only way to go is a flawed argument. Cheers Al I assume you get the fills for Frazer so this is not a particularly relevant point unless you going to sort out fills for me as well. I am aware of Kent Diving in Dartford and Dive Machine in Tonbridge wells who do mix fills. There is Lakeside as well but I don't know how much he charges as It wasn't open when I dived OC. I am also aware you get these incredible prices but I just don't have access to such cheep fills. I simply couldn't do a 70m dive on £60's worth of gas. Even home brew it would cost me more than that. A twin set of 17/50 costs £101 for Kent Diving, a 7 of 21/35 is about £20 a 10 of 50% is £9.00 and a 10 of 100% is £25.00 So my gas bill from the shop would be £155 + at least two trips back and forth to the dive shop which for me is over 120miles of driving. Home brew from garage fill man I am looking at about £110. He has to cover his compressor running costs, tank rental and make some profit so I don't complain. However he has gone CCR and will no longer fill twin sets. It was this move that forced me to consider my options and go CCR it was either that or put a limit my annual trimix diving. So 32 dives = £4960 in gas. + driving costs Home brew = £3520 For you = £1920 On CCR = £480 That includes gas lime and disposables. And I only need to go to the dive shop once in about every 10 dives to fill my bank tanks. You have demonstrated in the past that by running twin 12s and keeping the bottom times short, you can do the diving much cheaper than this. However I am not prepared to do less than a 30min bottom time and generally aim for 45mins. Whilst you believe that CCR is inherently dangerous, I don't share that belief so safety is not the issue here. Analysis of CCR incidents has shown me that basic diver errors and cutting corners on redundancy, were the primary causes of death. These are the very issues I would hope DIRebreather will address. I have done my best to analise all the available information on CCR fatalities and I haven't been able to pinpoint any death that could be directly attributed to the electronics of the unit. Whilst they can and do fail it appears that in some incidence it has been the diver failing to carry out a successfull bailout that resulted in death. A situation that could be easily avoided with the use of suitable off board bailout gas and a BOV. Sadly in many cases its the failure of the diver to monitor his situation (see my point on the HUD) or to carry out suitable pre and mid dive checks that has resulted in the incident. If disagree and you have a case history you wish to discuss, I would be pleased to go through it with you. Whilst your for telling of my demise via a PP02 hit may well come true some day, it wont be for want of trying to avoid it. I do have a wife and kids after all. When my unit spiked at 2.5 at 68m my HUD informed me of the problem immediately the unit passed 1.6. However the spike grew in seconds. I was able to dill flush quickly so i was probably breathing elevated PP02 for 30-40 seconds. Since that incident (and because of it) I have fitted a Bail Out Valve. (BOV)If it should occur again ill just turn the valve and go OC which in practice would put me on a safe gas in under four seconds. I believe most peoples feelings on the CCR issue are based on a lack of understanding of the units. Most anti CCR divers have never had any training to dive one. Sadly i also beleive present training is not focused enough and needs review. ATB Mark Chase __________________ The only DIR Inspiration/Hammer head/KISS/rEvo/JJ diver in the village www.ourturkishvilla.co.uk Last edited by Mark Chase; February 3rd, 2007 at 04:35 PM..

February 3rd, 2007, 04:56 PM	#24 (permalink)
jerry.mobbs(Offline) New Member Join Date: May 2006 Location: asia Posts: 294	Quote: (Originally Posted by Mark Chase) When my unit spiked at 2.5 at 68m my HUD informed me of the problem immediately the unit passed 1.6. However the spike grew in seconds. I was able to dill flush quickly so i was probably breathing elevated PP02 for 30-40 seconds. Mark Chase any idea why this spike happened? cheers jerry __________________ -------------------- www.crossfit.com The DIR of Fitness

February 3rd, 2007, 06:08 PM	#27 (permalink)
Howard Payne(Offline) The Voices And The Becks Join Date: Nov 2005 Location: London Posts: 1,897	So get together with Zak, Chasey, Janos, Digger and anyone else who's interested and try and thrash something out that's workable. Strikes me that you've just got to go for it and then a system will evolve from there? Genuinely wish you all the best with it __________________ Eastbourne Sub-Aqua Club 0513 Nitrox & Trimix, Club Boat, Plenty of Good Value Diving, Regular Club Trips & Holidays, Rec & Tech Training, GUE / Hogarthian Friendly Come Try Us! Last edited by Howard Payne; February 3rd, 2007 at 06:11 PM..

February 3rd, 2007, 05:03 PM	#25 (permalink)
onthetrain(Offline) New Member Join Date: Dec 2005 Location: Poole Posts: 11	Quote: (Originally Posted by Howard Payne) Therein lies the problem with this whole idea I put this same arguement to a CCR diver well known on the the UK circuit a while back and he said its badly needed but it aint gonna happen. As he pointed out - if you turn up to do a deep dive on a CCR boat - everyone will have completely different kit, different gas, different bailout and a different set of protocols and deco "requirements". In spite of the fact that everyone's there to do exactly the same dive. People derive comfort from thinking they've got it all worked out with all their modifications and idiocyncracies. In order to make this idea work - people would have to be prepared to give up what are for them "cornerstones" and in some cases adopt kit or practices that may be in their eyes either bestways "different" or worstways "inferior". You have to give up what gives you "comfort" now to gain a greater "comfort" from standardising training, gases, kit and bailout etc Can't see it happening myself - too many mavericks - too many big egos Howard this is a little bit of a flawed argument mate. It's a bit like saying all OC divers are DIR! Most are not, because there are too many mavericks, and big ego's etc etc. The simple fact (for me anyway) is that DIR is not for everyone. Many people do not like the strict team protocols, the kit standardisation etc etc. Those who frequent this forum do. Its clear that Myself, Chasey, Janos and others find the concept an interesting one. I dont think a DIR CCR system would work for everyone, as it doesnt for all OC divers. What I am saying is that diving A CCR could be improved for some of us through standardisation. Alan. PS Clare thanks for trying to shut down the OC V CCR cost argument. In my view it does not fit with what I am trying to explore here. Thanks for your views so far folks. Keep them coming Alan

February 3rd, 2007, 05:05 PM	#26 (permalink)
onthetrain(Offline) New Member Join Date: Dec 2005 Location: Poole Posts: 11	Quote: (Originally Posted by EBT) Its not happened, or its not widely discussed on the internet because some people prefer to do, rather than talk (no, its not me) Onthetrain, if you're serious; Eau2 Technical diver training, cave diver training, trimix and rebreather courses in UK, Europe and World-wide, dont be put off by the website, use the contact option. Regards, /Zak Zak, will you be at the dive show? If so maybe we can meet up to discuss the options? Alan

February 3rd, 2007, 08:11 PM	#28 (permalink)
Mats Edenfeldt(Offline) Cave is fun :) Join Date: Dec 2005 Location: Sweden - Stockholm Posts: 158	Lets break this down a bit more and lets try to find what you need as a minimal standard for equipment and team. This is how I would approach it. We already have this, this is absolutely basic. Use OC if it can be done on OC Have enough gas to be able to bail out and do the remaining dive on OC Team awareness, dive in team and use same gas and same equipment What kind of equipment is usable and what kind of equipment is not in to much violation of the basic DIR principle. As I see it first of all take the electronics out of the picture totally. Po2 monitoring sure (aloast a must when talking about CCR?!?!) but to have the rebreather relying on electronics primary is not OK as I see it. It needs to be simple in the design and simple to use with standard gasses, also the whole team need to have the same kit/configuration. Also deco on some sort of computer linked to the unit should also be taken out of the picture, so now we have a basic and quit simple machine. But how about the redundancy and the bail out and the gas management? First of all I would look at the use of a rebreather after 50-55 meters, before that it can be done simple and quit cheap with ordinary DIR kit OC rig. The rebreather as I see it is a bonus, as long as it works it works and the dive can be executed as planned, if it does not work tuff shit go back on OC and abort the dive. To use the rebreather this way i think its easiest to apply the standard gases, the GUE standards is a good base. Then an OC bailout can be done at any time. Should the deco be done on the RB or on OC? I think its more safe to do it on OC + you can use more of the standard deco method. If I am not to far out there a rebreather diver keep the po2 higher during accent and in this way does the deco and this in collaboration wit some sort of on board computer…right!!!? But here we come back to the core of the problem if you get a rebreather just to make it easier for you it gets lost right here because you still need to have the deco bottles and bottom stages to do the dive. Maybe with the kit below you can use the back mounted tanks for bail out, anything less for a 70 m dive is to little. A rebreather must be seen as a tool for the job and if its not needed don’t bring it. It can also be seen as a gasmanagement tool and something that makes an expedition easier. The RB80 does this in a great way but a CCR does it better, but the CCR demands more of the diver and the team if you where to use it in a more DIR friendly way. I would love to do some CCR training just for the fun of it and because I am curious, I will not use it for my kind of diving but just to learn more about the equipment on the other side of the fence. Mark you say you want to get more of a standard and more of a DIR approach with CCR:s…what is your suggestions and what problems in the above written can you see? __________________ GUE: DIR-Fundamentals, Cave 1, Cave 2 NAUI: Trimix 1, Technical diver, Instructor, DM, Wreck penetration, Oxygen service technician IANTD: Advanced Nitrox, Nitrox Various: Apeks tech, Poseidon tech "Doing it right really means to do it properly. No skimping and no compromises. It sounds easy enough but it is not - it requires balls of steel" Peter Steinhoff

February 3rd, 2007, 09:02 PM	#29 (permalink)
Ahmed Adly, Marlin Inn DC (Online) New Member Join Date: Feb 2006 Location: hurghada Posts: 1,078	I don't see anything bad about this configuration. Tell me if I am wrong but it is a KISS CCR rigged like an RB80. Well, this is what I was always talking about basically which is RB80 style but substituting SCR for CCR. As long as the team has standard gasses and the back gas is enough to bail out on, I really don't see the problem, except that I still like the idea of continuous F02 (for some reasons). __________________ Life and Death, although stemming from one another, seem to conflict as stages of change. Ahmed Adly, www.deepvoyage.com

February 3rd, 2007, 09:47 PM	#30 (permalink)
Mark Chase(Offline) New Member Join Date: Nov 2005 Location: Kent England Posts: 1,069	Quote: (Originally Posted by jerry.mobbs) any idea why this spike happened? cheers jerry A problem with the new Aluminum hand sets and SS battery caps. Aluminum oxide build up on the thread in the hand set causing failure of the circuit under load (ie when the solenoid fires). As the battery's performance drops off (due to dropping temperature at depth and the use of akoline batteries) The controller switches off. When the solenoid stopped firing the circuit was reestablished and the unit booted up. In doing so it tested the solenoid by firing it for three seconds and injecting a big slug of 02 into the loop which at 68m doesn't take long to spike the PP02. Firing the solenoid causes it to shut down again and so on. The problem was solved by using a conductive antioxidant on the battery cap thread. ATB Mark Chase __________________ The only DIR Inspiration/Hammer head/KISS/rEvo/JJ diver in the village www.ourturkishvilla.co.uk