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Further to the last TDI NITROX posting, I was wondering exactly what knowledge the advanced course "gets" you and what are its practical applications?

The main rason I ask is for the issue that I mentioned previously of planning for redundancy for the kind of diving I am likely to be doing in the near to medium future.  Aditionally, for example, how big a twinset should I realistically have to get to last me for the forseeable future?

I'm not planning to find the lost city of Atlantis or anything, so I doubt that twin 18s and four stage bottles are quite for me!!  (was thinking along the lines of twin 7s or 10s)

Ta very much
 

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Hi

I've been thinking about this myself for a while. TDI advanced nitrox I think is taken using twinsets and a deco cylinder. So its more about redundancy using a twinset. In the TDI scheme your basic nitrox I think is the basic lecture stuff and so using Nitrox for Deco is the theme of the Advanced Course, much the same as IANTD.

As far as what size to go for I thought of twin 7s but I'd need two sets or even three for some days. Twin 10,s not quite big enough for two dives but could use a 15ltr and transfill whip to top them up. I decided to go for twin 12's, cos I can comfortably do two dives off a rib and hopefully as I progress to deeper stuff I won't grow out of them. The only downside is the weight of the cylinders.

Hope that helps

WL
 

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TDI Advanced Nitrox, IMHO should be taken rather than the two courses (intro and adv) done separately.

You cover everything in the Adv course that you do in the Intro course (Intro course cert's you upto 40% mix) with added bonus that the Advance course gives you the extra theory, practise and dive skills that cert's you to use upto 100% O2 and certain deco proceedures.

I can't see a reason (other than an individual's budget and available time) why anyone might want to do the two courses separately. We completed the whole TDI Adv EnO2 course in four dives in two day's diving (two in Hodge Close and two in Wastwater - both in the Lakes) with the exams on top of that.

You don't need to be diving on twins to do either course - a single is fine. From memory, the TDI Intro is two dives and the Advance Nitrox is 4 dives.

HTH.
 

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THe advantage of twin 7s or even twin 10s is that they're light enough to use as standard everydive kit (I don't use anything other than my twin 10s except in the pool). Twin 12s are for me on the borderline between everyday and special use, guess it depends on your build and fitness etc.

Also depends on what BCD you've got: you can get away with twin 7s without a heavy-duty BCD, but for 10s you'd probably want something more substantial eg Buddy Commando or Tekwing or one of the more expensive wings perhaps
HTH
Steve
 

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Bren has made some good points there but I think if given a choice again I'd do it differently....

What I would recommend is to save some money now and just do the entry level nitrox.... you'll never dive over 40% yet anyway.. not unless you intend to go out and buy specialised nitrox clean equipment... better to spend the money you would waste on the advanced now and invest in some new dive rig... then later if you feel that you do want to progress further and are willing to invest time, money, and decompression stops.. then and only then would I progress onto the Advanced and at this time I would combine it with Deco procedures which would teach you how you use it correctly for advanced deco..

So to summarise...
TDI Basic Nitrox now..
Combined TDI Advanced Nitrox and Deco Procedures later when you feel you're ready to go down that route.

The latter two go hand in hand anyway

All the best whatever you choose
Dave
 

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I'm with Dave on this one

I'm in the middle of doing the Advanced and the Deco course with Andy now, however I might never use the Deco stuff at this time.
BUT I have learnt a lot of things which should be planned for at the time of all dives and hope to incorporate them in future dives.
Perhaps what a lot of divers needs is a 'instruction course' where information can be provided, kit analysed, advice on future direction of training and equipment provided. All without some-one making a lot of money

Deco proceedures maybe I won't need it yet, but for the price the tips alone were well worth it
 

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Thanks very much for your thoughts people - one thing I will say before anything else (and slightly off the subject), is that I apologise for no being able to respond straight away!  Can't seem to get extended periods on the net at the mo, what with work and all, and have been annoyingly busy in the evenings, so please don't think me rude if it looks like I'm ignoring your good advice!!

Back to the matter at hand though - the instructor over here is actually proposing to "package" the basic and advanced NITROX in one go for the princely sum of £180 (don't know how this compares with others).  My friends and I are supplying all equipment, as well as the boat and fuel, so if this appears cheap that may well be why.

Given this option, would that affect your choices?

Also, in response to Steve, I have a Halcyon plate & Pioneer (singles) wing, so would have to upgrade to a 55lb explorer when getting a twinset.
 

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Could someone clarify for me at what stage you need to get cylinder/regs O2 cleaned?  I keep hearing people mention this, but I'm never sure if its because they have to in order to use any mix of Nitrox or only specific mixes?

thanks
sam

(Edited by Sam at 11:35 am on Jan. 31, 2003)
 

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Any time a Nitrox mix of over 40% Oxygen is used, the equipment must be O2 clean.
Cylinders must be clean even if used with lower mixes, as pure Oxygen is put in during the Nitrox-mixing process. Unless you aren't filling by partial pressure.
 

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A word of caution about "O2 clean standards"

Apparently there seems to e two levels of "O2 clean" in operation these days, last november I bought an "O2 clean" litre stage from Diverswarehouse, later I noticed that the sticker states certified for use with O2 mixes up to 40%, Andy Hayhurst told me, IIRC,  with that "standard" of "O2 cleaning" all they do is check that it doesn't have loose particles of metal in it!

Also, I believe there are some issues with certain metal (titanium? aluminium?) bodied regs and nitrox use ,  I think Drifty has a link to this topic in an older post
Chee-az
steve
 

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I did tdi nitrox on its own, plan to do adv nitrox and deco together at the same time as ive been told there the best two to do together.
 

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Hi

When do you plan to do that Ben ? And have you thought who with ?

Cos I plan on doing the same. If its later in the summer then we could do it TOGEVA !

Kindest Regards

WL
 

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WL - I can't speak for Ben but I'll be doing the Deco Procs with Andy "Instructor of everything" Hayhurst during the Summer. I've spoken to Ben and were gonna try and get that sorted soon-ish.

I'm sure they'd be room for another - or in fact others.

Me and Ben are off to Scapa in late Sept so we'd be wanting to do the course three months before probably.

I'd imagine we'll have to move quickly cos the boy Hayhurst is busier than a busy thing.

Ben'll post on this on Monday.
 

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WL, Ben & Gav,

You might find that Stevie Walker, the Lesser-spotted Willo and miself are doing the Deco course with La Hayhurst too.

Err....do I feel another Troop Gig coming on..? Call the cops and hide the Sherry!
 

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Sorry for this a bit of a late post

Just to clarify a point raised by Steve W (and this isn't having a go at him)
You can't have a sort of/not quite O2 clean cylinder it either is or isn't. The blender will not add pure O2 to a cylinder which is not in test, does not have the visual inspection sticker and does not have the Nitrox stickers. He or she will also refuse to fill a cylinder which they believe has been filled with anything other than triple filtered air.
The reasons.
1. It might cause grease to burn inside giving carbon monoxide killing you.
2. And the most important it might explode killing the blender.
So if you are sold a cylinder and the shop tells you its sort of O2 clean add another £20 and get it cleaned or go else where.
Diverswarehouse will only put stickers on after they have cleaned cylinders

Hope this helps.
 

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Beleive it or not you can do the advanced Nitrox TDI course on a single 12 and no stages??? I dont know why. All in all the in water skills were SAC calculation first dive. (I did this in twin set and buggered the instructor as after 5mins at rest my presure gauge had not mooved). This is 5 mins at rest calk then 5mins normal diving and finaly 5mins finning like bugger against an imoovable object.

Then it was SMB deployment by two diferent methods

Then it was holding schedualed deco stops and maintaining set ascent rates.

We did shut downs for a laugh but I was told it was not esential.

The exam was a bit of a joke as they asked me to do the impossable IE plan a best mix dive bassed on tables. Unfortunatly the tables provided did not cover gas switching to enriched nitrox for accolorated deco so this was impossable.

This was agreed with my instructor and then I showed him how I would plan it on deco planner on my lap top and he was happy enough to pass me.?


All in all the course in my case was an easy route to enriched nitrox to 100%.

Bearing in mind my instructor had little or no experiance of gas switching deco dives and did most of his diving in the Red sea and I had done over 30 such UK dives at that time my course was a joke. That said I blame that on the dive centre not TDI. The course material was good and the exam was OK but the standard of training I received was crap.

I swaped instructors and went on to do Deco Procedures. The instructor again pointed out to me that I didnt need stages for the course?
?
???. Training this time was good but I was dissapointed that I could get all the way to deco procedures level and not oficialy receive training with stages.

Doing TDI entry level trimix now will report back when finished.

Mark Chase
 

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Thanks for that Mark,

Adv Nitrox can be done without twinset and why not. Not everyone needs 24l of gas for a dive and you can still apply thirds with 15l.

I hope your trimix trainer will be better than the other guy you had  - howevere if you are worried about the level of training you received then maybe it'd be better re-doing the Adv-nitrox and decco course first?

I can certainly recommend Mr Hayhurst and so can a cast of thousands.

Bren - sounds mighty fine. I'm sure that me, Willo, Steve W and Ben will keep you on the straight and narrow - make mine a meths!




(Edited by Gavin Yates at 8:25 pm on Feb. 1, 2003)
 

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Im up for whatever dates you guys want. Twin sets on order as we speak!!

gav apparently theres a customs strike somewhere on the continent which is why everything from USA is taking ages to get through, your wing and my dads bathroom tiles!!!!!!

Bren and co, when you thinking of doing the courses??
 

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Mark, I puzzled over that (or I imagine a very similar)  "impossible" dive plan and concluded that it was designed to (a) test your understanding of what depths it was or was not appropriate to use nitrox, ie you were meant to find there was not a best mix for that dive and (b) to make you demonstrate on paper a detailed dive plan. The lack of accelerated deco planning, due to use of the air tables, didn't strike me as an issue as my perspective was that I would be using nitrox for extended safety margins rather than to speed up deco. I was under the impression that accelerated deco would be part of the Deco Proc course as, IIRC, it was only touched on briefly in the Adv Nitrox theory part (Bren, Dave Gav: what do you guys remember about this particular topic from the course?)

Andy W, re O2 cleaning: don't worry, I'm not taliking your comments personally, I was under the same impression that you are, ie it's got a sticker so it must have been O2 cleaned, mustn't it?.
However... The sticker clearly states (and this is a verbatim quote) "Tank & Valve Have Been Cleaned For Premix, Oxygen Content 22% to 40%".

As this is the only nitrox tank I own I don't have another one handy for comparison, but incorporating TWO disclaimers ('premix' and '40%' limit)does not sound to me like a proper O2 clean. I may possibly be wrongly remembering Andy H's comments about the O2 clean status of this tank, but my previous comments were correct according to my memory.

So does anyone have an O2 clean tank with a recent sticker that states anything different to the one on my tank?
 
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