Mexico CCR Cave Training Report

[cgrosart]

Originally Posted by Gareth J

Sorry if this is seen as a thread hi-jack, it is not meant to be, but replys may warrant us opening a new thread.

I have read the Chase, Howard, Jano's trip report with interest.

The critisism that they didn't enjoy the caves seems a little unfair. They have said the caves where interesting, but the report is on the course. Having done courses overseas myself, I can fully understand that your focus is on the course not the enviroment.

From my view they seemed to have explained the 'course' at length & the impact of the stress involved on each other & the team as a whole. This I found extremely interesting. Within this they have also documented each & every kit failure no matter how minor. In fact, they highlighted the most minor failures & how this impacted on the abort routines they adopted & again the effect on the team.

I feel it is a shame that the thread is deteriorating into an argument about the strenghts & weakness's of CCR & OC. If we wish to discuss this we should start another thread.

Please remember on OC failure to a non-diver seems very dangerous, even if to a OC diver it is a easy to resolve mitigate.
For most OC divers, CCR take on the same degree of seriousness, although for the CCR diver it may well be a minor irritation.

Gareth

See here : Entry level Cave diving - OC vs RB

[AM1]

Hiya

Originally Posted by cgrosart

If the line breaks, deploy the search reel and conduct a search. A compass will help with this. Knowing the general direction of 'home' and using any flow direction gives huge clues, as with topography.

Yes of course, my point being that if the CCR fails and you're back to OC, you're still back with the time limitations aspect so no point taking the mindset that a CCR makes it safer. Search reels don't always find the line quickly, as you know, it depends on the passage, nav errors are easy to make - look at the wrong turn taken by JM in the Ressel several years ago. A CCR only makes a cave dive logistically easier and it only makes it safer (time to solve a problem) until it fails. OC bailout is still crucial.

Originally Posted by cgrosart

I can assure you that CCR is most definately not the way forward in the cave that I am pushing !! It simply won't fit When Rick pushed the Fontaine de Truffe last year, he took his rebreather off at the terminal squeeze, switched to Open Circuit to pass the most nasty bit of the cave - then switched back to sidemounted rebreather again ! OC has it's place........We all used OC to support him. Mark's comments make it sound as if we are lucky to be alive. I'm sure this was not his intention.

In context, it was a general comment aimed at beginner cave divers. CCR is the way forward for beginner "tourist" cave divers ( no offence meant by this). Why bother learning to cave dive in Mexico on OC now, there is simply no point unless you intend to dive tight sumps that will require OC to pass through - I know of no sumps in Mexico that would fit this description. I don't think it's a valid comparison to compare Rick's push dives at the Truffe, but if Mark hurries up, he might catch up In any case, Rick is too tight to keep using OC and is using the Micro RBs now to get around having to use OC for tighter squeezes the time is approaching rapidly when the advent of smaller and smaller units negates the need for OC to pass restrictions. I will be supporting Rick in France shortly (for some of the trip) and will stick with my normal mode of CCR, simply because there's no benefits to gain from doing it on OC and more logistical headaches in doing so. OC has it's place, in my view, for bailout but not for long OC penetration dives any more or for beginner cave divers to switch back from CCR to OC for a course. Why bother, from a logistic point of view (unless you're part of the DIR machine with huge resources available and too stubborn to admit that CCR is the way forward)

Originally Posted by cgrosart

BTW - The reason Mark is getting a hard time is because of a previous thread where the argument for/against cave TRAINING on CCR was conducted. It has been done to death and been dredged up by the otherwise, good report. I just wish people would think before they make bold comments such as OC cave diving being dangerous. Especially when they have no experience of it. We use the tools for the job - one of these tools is Open Circuit. I once heard a quote from a cave diver who has been cave diving for 20 years on OC and is still cave diving at 62. He stated that these days, the risks of cave diving are 'manageable'. It just depends how you manage them!

I haven't seen that. But the web is full of people commenting from a position of no context - my very first cave dive was on OC simply because at that time there was no rebreather small enough to fit. There is now. I'll take a look at the thread, sounds interesting!

Originally Posted by cgrosart

For the reasons AnneMarie states regarding OC bailout, I think you'll find that the reason cave divers switch to CCR is so that they may go further and deeper than logistically possible on OC, or need extra time for working at depth i.e shoring up a boulder choke or drilling. They don't have a habit of doing it to make dives that are well within the limits of OC safer. But if using a RB makes Mark feel safer, then fine. So long as he is under no illusions, especially on the back of some good posts on these threads, that he may not always be. I don't think I can make fairer comment than that.

Yep, absolutely agreed. The minute the CCR fails it's back to OC bailout, which is why prevention is better than cure.

[cgrosart]

The comment about cave diving's risks being manageable was made by Clive Westlake.

I don't think new, tourist cave divers should learn on CCR with OC bailout for the reasons that Clare Gledhill stated in her reply on the OTHER thread. In a nutshell, you need to know what you can/can't achieve on OC before you are forced to rely on it when your RB goes wrong. If you have an aversion to cave diving on OC, the only way I can see that learning to cave dive on CCR is acceptable is if you have CCR bailout.

I'll see you in France then I think a cast of thousands are going to be helping Rick, which should keep him happy !
p.s He was only still working on his prototype nano-rebreather at the time of the Truffe push. We had to hear about it all the way down to the Lot.........

[AM1]

I thought as much!! I saw Clive on Monday,trying his new scooter. Rick of course amused us all by boasting that the swiss homebuild "could not go wrong with no electronics" then could not use it due to mis-assembly (bad o-ring seating). Highly amusing!!!

Which France trip do you mean, the one coming up shortly, or one of the ones later in the year? I will probably be Rick's only support diver on the forthcoming trip then we'll separate for individual projects for the remainder of the trip. Might well see you later in the year!

Anyway sorry Mark for hi-jacking your thread. I still think CCR in a cave is the best way to learn now, if you are a decent CCR diver then you know and understand the necessities of OC, especially if you practise proper bailout planning already in open water. Most decent wreck divers know and understand what they can achieve on their OC bailout, hence if they switch to cave, there are still those same logistics (albeit more complex) to consider. CCR cave diving with CCR bailout still warrants OC gas in my view, this is another one that's been done to death!!

If divers can't execute a CCR dive with appropriate OC gas planning, they have no business being near water, never mind a cave.

PS - the nano unit's come a long way.

[cgrosart]

Who judges whether they're decent RB divers or not ?

Thread number one thousand and...................

No, I'm talking about the summer. We just got blown out of a trip to Switzerland to dive Rinquelle - weather turned

[AM1]

Yep, a real shame about Rinquelle, but hey ho.

Aaaah....decent RB divers Go on, start a thread. Look what you've done Chasey!!!

Anyway, maybe this OC vs RB discussion should be continued in t'other thread. I'm going to read it now, see you there.

Sorry Mark.

[Mark Chase]

Originally Posted by cgrosart

The comment about cave diving's risks being manageable was made by Clive Westlake.

I don't think new, tourist cave divers should learn on CCR with OC bailout for the reasons that Clare Gledhill stated in her reply on the OTHER thread. In a nutshell, you need to know what you can/can't achieve on OC before you are forced to rely on it when your RB goes wrong. If you have an aversion to cave diving on OC, the only way I can see that learning to cave dive on CCR is acceptable is if you have CCR bailout.

I'll see you in France then I think a cast of thousands are going to be helping Rick, which should keep him happy !
p.s He was only still working on his prototype nano-rebreather at the time of the Truffe push. We had to hear about it all the way down to the Lot.........

Why the hell you lot cant get your head around the fact I am talking from a personal perspective I have no idea. I mark chase feel more comfortable doing big wreck penetration or caves on a CCR. Having the extra gas in no way reduces the need for knowledge skill and caution. I believe time stress is a killer. Full stop

However I very much enjoy talking about diving and I learn a lot from the comments of more experienced divers so i am perfectly happy to stick my 10 hours of cave diving head above the parapet for your combined target practice. I might learn something and I am totally open to changing my view with further experience. I have done with CCR. The way i dive CCR now is totally different to the way i started and I wouldn't go back to my old ways.


Fire away.


The fact of the matter is the course is a CCR cave course and I dive a CCR so it seemed logical to do it. It doesn't qualify me to dive caves OC Id have to do another course for this.

The CCR course is different to the OC course specifically in the area of bailout

I find it an odd comment that there is any relevance at all to what can be achieved on OC in an emergency situation.

In my view very little can be achieved.

You either have enough gas or you don't. (You could breath the wing I suppose but thats got to be option Z and lets face it your using it as a SCR.)

CCR of course, is a totally different ball game. In board gas can be run semi closed. We have all been taught 4:1 ratio SCR. More experienced CCR divers have no doubt done what I have done and seen just how long it takes to breath down 1.3 to 0.4.

So on my inboard diluent I have the possibility of pushing my 3ltr with 150 bar in for 15mins minimum on a 4:1 and 20-25mins if i chose to run a diluent with a higher PP02 (which i would)

Then their's my off board 11.5 ltr 200 bar

My sac OC is around 12 working 8-10 resting. I generally gas plan on 15.

So OC bailout ignoring the CCR will give me an hours breathing gas.

Assuming stress virtually doubles my normal SAC to 20 I have 48mins

But i dive a CCR with a BOV so i can also run my diluent SCR as well so even with my raised SAC I now have 192mins

SO OC I have 48mins bailout CCR I have 207

BUT I hear you scream, what about a total unit flood?

Simple, Buy a unit that doesn't generally flood and has excellent flood recovery.

Much as i dislike the inspo it has fantastic flood recovery and would have avoided the problems I had on the KISS. I haven't dived a Meg in anger but seeing as it has a similar water trap system to the Inspo I would seriously consider a Copis MCCR Meg as a better choice than the KISS for this sort of diving.

So my conclusion as a total novice who dont know s#it about caves (but as a CCR diver with 4-500 hours experience) is that CCR greatly expands your options on bailout and straight OC bailout is both limited in application and of only limited significance to a CCR diver who dives the right unit.

Knowing what can be achieved on OC is a simple math question. I breath this much at this depth and I have that much gas. Allowing for stress i have X time. Thats about it isn't it? Why do i need another course to lern this, I did it in PADI AOW.


ATB

Mark

[NotDeadYet]

Originally Posted by Mark Chase

Why the hell you lot cant get your head around the fact I am talking from a personal perspective I have no idea.

Because you're wrong, just accept it

CCR of course, is a totally different ball game. In board gas can be run semi closed. We have all been taught 4:1 ratio SCR. More experienced CCR divers have no doubt done what I have done and seen just how long it takes to breath down 1.3 to 0.4.

Do an hour or two's swim SCR and see how you feel at the end of it. I'd rather go OC, it's absolutely exhausting, it takes a lot of focus, it screws your buoyancy up...

So OC bailout ignoring the CCR will give me an hours breathing gas.

Assuming stress virtually doubles my normal SAC to 20 I have 48mins

So on OC you will be stressed and your SAC is through the roof. Why isn't the same going to be happening on SCR? So you're stressed, you're breathing hard, you're sucking on an ADV that feels like giving someone a blowjob down a mile of garden hose every 4 breaths all whilst swimming, all whilst trying to find your way home, all whilst your buddy is swimming along happily thinking "what a cock, why doesn't he just bail out?"...

I've had a RB failure 2hrs from air and I nearly inhaled my drysuit through my arse. I didn't give a flying f**k what I was breathing as long as I could breathe it. Psychologically, once I was on OC there was no way I could have come off it to go back on SCR. And psychologically there was no way I was about to go through some mental checklist about how to stay on the loop. I needed to breathe something, I needed it NOW and once I'd got it you'd have to pry it off me to get me to take that 2nd stage out of my gob and put a DSV in.

BUT I hear you scream, what about a total unit flood?

Not really, that's what OC is for And in my very limited experience of swallowing lime I'd be very unlikely to stay on the loop where I don't always have control of my position -- you point where the cave points you.

Simple, Buy a unit that doesn't generally flood and has excellent flood recovery.

Erm... weren't you diving a KISS? Not exactly flood resistant/recoverable.

So my conclusion as a total novice who dont know s#it about caves (but as a CCR diver with 4-500 hours experience) is that CCR greatly expands your options on bailout and straight OC bailout is both limited in application and of only limited significance to a CCR diver who dives the right unit.

OK, what about a CO2 hit underground? OC still of limited significance?

Why do i need another course to lern this, I did it in PADI AOW.

Well, you did the course so why did you need to re-learn it?

[Mark Chase]

[quote]

Originally Posted by NotDeadYet

Because you're wrong, just accept it

Its like my marriage. If something goes wrong i know its my fault i just can't always figure out how or why

Do an hour or two's swim SCR and see how you feel at the end of it. I'd rather go OC, it's absolutely exhausting, it takes a lot of focus, it screws your buoyancy up...

Get a BOV is far less exhausting SCR. But your right when i did SCR for over an hour I got a very sore nose and a head ache.

Id plan OC but if I hit a problem Id go SCR till i was sure my OC was enough to get me out. I wouldn't bother unless it was necessary. i was just trying to point out to the non CCR diving critics on this thread that the CCR does offer more options even when its broken

So on OC you will be stressed and your SAC is through the roof. Why isn't the same going to be happening on SCR? So you're stressed, you're breathing hard, you're sucking on an ADV that feels like giving someone a blowjob down a mile of garden hose every 4 breaths all whilst swimming, all whilst trying to find your way home, all whilst your buddy is swimming along happily thinking "what a cock, why doesn't he just bail out?"...

I did do the SAC calks on 20 which is pretty stressed breathing for me. My normal sac is around 12.

I've had a RB failure 2hrs from air and I nearly inhaled my drysuit through my arse. I didn't give a flying f**k what I was breathing as long as I could breathe it. Psychologically, once I was on OC there was no way I could have come off it to go back on SCR. And psychologically there was no way I was about to go through some mental checklist about how to stay on the loop. I needed to breathe something, I needed it NOW and once I'd got it you'd have to pry it off me to get me to take that 2nd stage out of my gob and put a DSV in.

I have no idea how i would react till i am actually in the cart but I am confident id go scr if i had to.

Not really, that's what OC is for And in my very limited experience of swallowing lime I'd be very unlikely to stay on the loop where I don't always have control of my position -- you point where the cave points you.

If you have the right CCR it shouldn't get that bad in the first place

Erm... weren't you diving a KISS? Not exactly flood resistant/recoverable.

Yep, I believe I was on the wrong re breather. Copis Meg with HUD would be my first choice.

I am already looking into modification of the KISS to stop it happening again.

OK, what about a CO2 hit underground? OC still of limited significance?

Never had a co2 hit, but bailout early and or go SCR would be the obvious reaction. Co2 can be retained C02 or a unit failure. If its retained then bailout isnt going to help that much. If its a unit failure then once breathing is back under control you may find you have used stupid amounts of your Oc gas and you have no choice but to go SCR.

Well, you did the course so why did you need to re-learn it?

Don't quite follow this? We didn't re learn SAC or gas planning on the cave course. We were expected to know it. It would be rather odd for a gas diver to not know how to plan bailout? Two hours out of the cave or two hours deco, the planning is the same.


ATB

Mark

[Miss Roxy Chablis]

feels like giving someone a blowjob down a mile of garden hose every 4 breaths all whilst swimming

Get me Digger on the phone someone will you?