OC Trimix - Are you kidding me?

Randy Thornton

Randy Thornton

Administrator
Staff member
Was talking to a couple of guys the other day who were inquiring about taking an OC Trimix class and it dawned on me that I don't think I know very many people who are still actively diving OC Trimix. So my question for this esteemed group is: "Do you know anyone who is still actively diving OC Trimix and if so, what is there reason for staying with OC instead of switching to CCR?"
 
I know lots of people certified on OC Trimix. They are all doing air dives to 150ft 45m and haven't done a trimix dive for a while.


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Sadly I do not see many this day in age diving oc trimix, as the price of doing a single dive to 200-300 feet is nuts, go on a weeks trip and you just put blew a downpayment on a nice car.

Personally, I see oc trimix as a necessary step to learn the proper skills on how to handle multiple bottles. I've yet to see a ccr diver go straight to ccr trimix and be able to handle 3-4 bottles with ease or with confidence. Now that being said I am sure there are people who can and instructors whom are abke teach the necessary skills, but rarely have I seen any that can actually handle the bottles or even practice with them. Most just jump in with the bare minimum bail out (2 80's sidemounted, with leaky gear from 300 feet), and hope for the best it appears. Granted you can learn the bottle rotation stuff in shallow water (20 feet) but nothing beats getting the actual experience in actual conditions. It's a dying aspect of the sport, well sub 150 as the costs of doing any depth is going through the roof.

That is my two sense.

Steve
 
Aaen said:
Personally, I see oc trimix as a necessary step to learn the proper skills on how to handle multiple bottles. I've yet to see a ccr diver go straight to ccr trimix and be able to handle 3-4 bottles with ease or with confidence.
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Not sure if I follow the logic here. If you dive CCR and move to trimix you can't handle multiple tanks but if you go to trimix on OC you are instantly expert in this? Doesn't the level of skill in handling the multiple tanks build up from the time you start using them?
 
Never said you were an expert if you do oc trimix far from it. You just have the skills in place that are easily transferred over to ccr.

What it boils down to is that the vast majority of people I see doing oc trimix then eventually moving onto ccr trimix have the necessary skills to handle the increased equipment/task loading because they have practiced the skills beforehand and put the time in getting squared away. The ones I see jumping in on ccr trimix and not doing oc trimix tend to not have these skills and are an utter mess, sure they need to practice to develop these skills, but rarely do you see them practicing or working on these skills, because the tanks are for bail out only. I am sure some do, but my experience is most don't. Its painfully obvious when you see them in the water, just watch them clipping off tanks.

Being able to handle multiple tanks effectively and efficiently rotate the bottles is more then just dragging them around. You have to actually be able to rotate them, switch gases This is something that oc trimix divers do each and every dive. By having these fundamental skills the diver then has the capacity to carry a stressed buddy, trouble shoot and proficiently bail out to the required gases safely.

The logical progression IMO is to do oc trimix, ccr, ccr trimix if necessary.

Anyways, back to the normal thread of oc trimix and how many are doing it. Sorry for deviating.

Regards
 
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In the 45-50m range there are a number of OC divers in the UK, but the majority are air/nitrox diving. However, those who do it regularly are GUE trained from my limited experience.

Gas is expensive, but not as expensive as losing my life through not being able to think clearly!

Would it be cheaper doing it on CCR? Maybe, but Chasey will be along to determine the break even points for number of dives when you consider equipment, training, continuation training, sorb, cells...

I do not do enough trimix diving to justify spending £2-5k on a unit, £1k on training, cells and sorb, and I certainly don't do enough diving to keep my skills up on a CCR for trimix diving, although why anyone would dive air on a CCR is beyond me, even in 'recreational' depths.

I also don't have a team who I would be happy with diving CCR with. As such, I am happy to burn £10 notes when diving OC trimix ;)

Regards
 
I know plenty of folks diving OC mix. And I don't think Aaen's comment about the excessive cost of OC trimix is correct. When you figure in the cost of a CCR unit and training, it takes an awful lot of deep mix dives to even come close to breaking even.

Some of the folks I know are just not ready to go CCR. The fatality statistics are real. The learning curve is real. The additional risk is real. The cost factor is real. And they've been doing OC mix for a long time. The biggest problem I see is on big overnight outings like Doria dives. The OC guys are loading up the deck with 4-5 sets of doubles in addition to bunches of deco bottles. As the number of OC guys drops, the amount of space on deck increases.

Bottom line, Randy, is that we regularly read about accidents and fatalities on CCR. Throw in a $10K cost factor on top of that and there are plenty of guys who do 25 trimix dives a year that are quite content to stick with OC.

Ken
 
GLOC said:
In the 45-50m range there are a number of OC divers in the UK, but the majority are air/nitrox diving. However, those who do it regularly are GUE trained from my limited experience.

Gas is expensive, but not as expensive as losing my life through not being able to think clearly!

Would it be cheaper doing it on CCR? Maybe, but Chasey will be along to determine the break even points for number of dives when you consider equipment, training, continuation training, sorb, cells...

I do not do enough trimix diving to justify spending £2-5k on a unit, £1k on training, cells and sorb, and I certainly don't do enough diving to keep my skills up on a CCR for trimix diving, although why anyone would dive air on a CCR is beyond me, even in 'recreational' depths.

I also don't have a team who I would be happy with diving CCR with. As such, I am happy to burn £10 notes when diving OC trimix ;)

Regards
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I think the sooner training agencies see this the better.
As a new CC diver you can get a ticket to dive an air Dil to 48m,
I'm sorry but at that depth on CC I'd much rather be on trimix.
I have only recently moved to CC and like yourself I don't
do enough deep trimix diving to justify the cost of the unit.
For me the decision was made so I could use trimix in the depths
that you quoted. I also now have the option to do as much deep
diving as I like without having to take costs in to account and that
is what was limiting my trimix diving.
 
Edward poped on the boat the other week to do a OC mix dive with us but it was only 50m.

Apart from that I havent seen an OC rig on a mix dive over 60m for a few years.

Some say they dont do enough gas diving to justifie switching to a CCR. The point is once you switch you find you do loads more because it doesn't cost any more to do a gas dive than it does to do a Nitrox dive.

Its easy to work out how long it will take to pay for its self.

A CCR dive costs £15 in gas batteries sofnalime etc.

Deduct £15 from what it costs to do an OC mix dive and devide that into the cost of your CCR.


My CCR cost me £3250 + training say £4250.

It paid for its self in 18months to two years, and now I am saving at least 2k a year.

More importantly my average bottom time went up from 20-30mins up to 30-45mins so on CCR i was getting a lot more dive for my money.

With second hand KISS units ready to dive selling for £1050 on ebay, id say its possable to get on a CCR for £2500.

ATB

Mark
 
We still have a number of OC Trimix divers on the east coast. Randy, a number of people on the VBTech FB page- that you're on - fall into that category. Most are people who have been diving OC all of their lives and just can't/won't make the change. Money is often touted as the main reason, but it is a BIG mental shift for them, too. (Most of us older divers can appreciate where they are.) They often comment that they're the only one on the boats without a RB & that they know they should go to one.

To each his own, IMO. Can't say that I would enjoy paying for those fill, however.
 
Mark Chase said:
Some say they dont do enough gas diving to justifie switching to a CCR. The point is once you switch you find you do loads more because it doesn't cost any more to do a gas dive than it does to do a Nitrox dive.
Click to expand...
I am more time poor than money poor (although I could do with more of the latter!
Its easy to work out how long it will take to pay for its self.

A CCR dive costs £15 in gas batteries sofnalime etc.
Click to expand...
Based on how many dives? Surely a cell every 6 months (1st cell changed after 18 months) is approximately £120-180 in cells per year which needs to be taken into account. Unit servicing costs per year?
Deduct £15 from what it costs to do an OC mix dive and devide that into the cost of your CCR.
Click to expand...
So call it £25 per CCR dive in consumables and NRE for the servicing etc. For a 50m OC dive, cost is around £60-80 in gas, so £35-55 delta.
With second hand KISS units ready to dive selling for £1050 on ebay, id say its possable to get on a CCR for £2500.
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Servicing cost to the KISS up to where it should be? I wouldn't dive an unserviced unit!

So you need to do at least 80 T1 level dives to break even. However, that means you don't dive OC Trimix for however long it takes to get that money back. 80 T1 dives is around 2-4 years worth of diving...

Some say sell your OC gear to finance the CCR purchase but then how do you keep your in-water skills up, and how do you do the shallow stuff where CCR is really an overkill?

Regards
 
I saw a load of OC mix divers on my boats in Florida. Im still teaching it too.

It will be interesting to see if theres any market for it over here.
 
GLOC said:
Servicing cost to the KISS up to where it should be? I wouldn't dive an unserviced unit!

Some say sell your OC gear to finance the CCR purchase but then how do you keep your in-water skills up, and how do you do the shallow stuff where CCR is really an overkill?

Regards
Click to expand...

I wouldn't worry about the KISS, they're nails anyway and IMO you need to know your unit well enough to look after it properly. In fact I'd go as far to say that if you can't service it yourself you shouldn't be diving it. It's not PADI OW day 2 and "get your regs serviced by a grown up every year or you'll die" ;)

I don't see the sell your OC gear thing either, won't free that much cash up unless you've got silly numbers of twinsets. Although if you do loads of OC gas diving you probably have!

Don't see why CCR precludes in water skills, or shallow diving. Even little O2 CCRs for no-cost shore diving are good fun :)
 
GLOC said:
I am more time poor than money poor (although I could do with more of the latter!



Servicing cost to the KISS up to where it should be? I wouldn't dive an unserviced unit!

Regards
Click to expand...

Much as I am gratefull for Mark's generously shared wisdom on most matters about diving, I am calling BS on his continued harping on about the desireability of the old KISS. Has anyone out there seen an un modified KISS in the water recently? The KISS divers I go out with do well for not missing dives due to kit falure, but the units are far from stock. Many $$ are usually spent to bring one up to speed.

Any how, I would simply not be doing the dives I do now if it were not for the ccr. All I have to do if dive plans change is to grab another deco bottle or two. The thing is a joy to be in the water with.

I am diving much more with longer bottom times and I find I enjoy the fiddling.

I sugest saving the cost benifit calcs for the wife. I suspect there are more than a few rebreathers out there that "only cost a few hundred dollars dear". :devilban:

Peter
 
Peter Sotis did a pretty good write up recently comparing the cost of OC/Trimix to CCR, and it was about 3 years break even, and then the lower cost of CCR/Trimix quickly took over.
 
GLOC said:
I am more time poor than money poor (although I could do with more of the latter!

Based on how many dives? Surely a cell every 6 months (1st cell changed after 18 months) is approximately £120-180 in cells per year which needs to be taken into account. Unit servicing costs per year?

So call it £25 per CCR dive in consumables and NRE for the servicing etc. For a 50m OC dive, cost is around £60-80 in gas, so £35-55 delta.

Servicing cost to the KISS up to where it should be? I wouldn't dive an unserviced unit!

So you need to do at least 80 T1 level dives to break even. However, that means you don't dive OC Trimix for however long it takes to get that money back. 80 T1 dives is around 2-4 years worth of diving...

Some say sell your OC gear to finance the CCR purchase but then how do you keep your in-water skills up, and how do you do the shallow stuff where CCR is really an overkill?

Regards
Click to expand...

I'm not answering for Mark but I am a new Kiss diver who has been diving OC
for about twenty five years and diving twins since 1994.
I'm in a club that provides nitrox up to 40% at a fixed cost of £2.50 and richer
mixes at .0085p per liter I also mix my own trimix, so I'd say my gas costs are
about as cheap as they can be.
A normal 45m dive would cost me £5 in nitrox costs, if I use a single 40%
as deco gas and if I use an additional rich deco it rises to almost £20 (80%).
If I do a trimix dive to 60+m the gas costs me about £55 (18/35) plus the
deco gas at £17.50 so the total gas cost is £72.50.
To do the same mix dive on CC my gas bill would be £14 and that would be
with an 18/40 mix that's a saving of £58.50 before sorb, batteries and cells
are taken in to account.
Servicing costs on the kiss are very little, I have never known of one being
returned for a service though I'm sure someone may have. Basically the only
things needing any service by an outsider are the first stages, I honestly
can't see what else someone that can hold a screwdriver couldn't do
themselves.
Basically what I am trying to say is that if I stick to nitrox depths then OC
is the best tool for the job and works out cheaper but when trimix is being
used on a regular basis then CC, for me at least, is the cheaper option and
I also have the convenience of being able to change plans at the last moment
and not have to cry my eyes out at using trimix on a shallow dive. Though
the last point is a little muted as I keep one set of twins for nitrox and
another for trimix.
It's true to say that my diving has taken a step back as I'm still only a novice
CC diver but I would hope that I will soon be going back up to Malin and not
have to worry about taking a helium J and spending hours pumping gas every
evening.
All the above combined with the fact that I'm not as young as I was
in 1994 when I first dived twins makes the move seem like a good one.
I also appreciate your comment about not being able to keep OC skills
up to scratch but at the moment I can't see me going back even if CC
seems like overkill on some of the shallower dives.
 
PeterN said:
Much as I am gratefull for Mark's generously shared wisdom on most matters about diving, I am calling BS on his continued harping on about the desireability of the old KISS. Has anyone out there seen an un modified KISS in the water recently? The KISS divers I go out with do well for not missing dives due to kit falure, but the units are far from stock. Many $$ are usually spent to bring one up to speed.

Any how, I would simply not be doing the dives I do now if it were not for the ccr. All I have to do if dive plans change is to grab another deco bottle or two. The thing is a joy to be in the water with.

I am diving much more with longer bottom times and I find I enjoy the fiddling.

I sugest saving the cost benifit calcs for the wife. I suspect there are more than a few rebreathers out there that "only cost a few hundred dollars dear". :devilban:

Peter
Click to expand...

Any chance of some examples of these failures ?
I am genuinely interested as I am a new Kiss diver
with a mainly un-modified unit, GG BOV and VR3 is it.
 
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