View Full Version : Advanced Nitrox - was Recent Threads on Club Matters
The whole BSAC & 100% thing is doing the round over on Club Matters. TerryH made a post about Advanced Nitrox which I think is best discussed here
TerryH: Original post
<a href="http://www.bsacforum.co.uk/forums/clubforum/posts/1566.html" >http://www.bsacforum.co.uk/forums/clubforum/posts/1566.html</a>
Matt: Response
<a href="http://www.bsacforum.co.uk/forums/clubforum/posts/1573.html" >http://www.bsacforum.co.uk/forums/clubforum/posts/1573.html</a>
TerryH: Latest
:=:=1. Could you change Advanced Nitrox to Allow acelerated deco.
:=
:=BSAC have an accelerated deco course, ERD.
And it takes three days, is very involved. Costs over ?200 +
other expenses and for what?
So I can carry a pony/stage with upto 80% in it?
I think you need to consider the diving that the qualification is intended for.
:=:=This is a recognised (by all the other agencies)
:=
:=IANTD do not sanction accelerated at Advanced. ITDA do not have an Advanced grade.
:=
TDI, DSAT, ANDI, ETA ........
Some do, some dont. Wasnt being specific about the level either.
TDI do not allow deco at Advanced, you have to do the Deco Procedures course on top.
ANDI do not allow deco at Advanced (CSU) you have to do Technical (TSD) and ERD is a further course.
DSAT TechApprentice does not allow deco, you need Tecdeep which is similar in Duration to BSACs ERD
NAUI do not allow deco at Advanced (Technical). You need to do a Deco Techniques and ERD is a further course.
PSA well a bit different really, are they still going.
GUE teach a very specific way to use Nitrox.
Which I think covers every agency in the UK teaching > 50%. It is not just BSAC that feel Advanced is not an appropriaye qualification it is all of them. I guess TDI is about the fastest least time in the water route, possibly why it is so popular.
Anyhow your suggesting that BSAC should do something quite different to what is generally accepted. Is that what you intended?
:=There are risk and decompression strategy issues which are not taught on the Advanced course, baleout comes to mind.
Then limit the percentage. What's wrong with a bottom mix
of say 27% and an accelerated deco mix of 50%? There is plenty
I don't see any sense in limiting the FO2 if your accelerating. PPO provides the driving force to get the N2 out. The higher you keep the PPO:PPN the more effective the decompression, acceleration relies on this to an extent.
Personally I will no longer use anything under 70% for acceleration. I end up with those nasty sub-clinical symptoms I associate with long air decos.
of scope in the current course to include bailout issues as
part of the redundancy section.
The bailout is easy, you must be prepared to do the stop on your bottom mix. You must carry the gas, have the thermal protection and be able to cope with the fatigue. Personaly I think people should have the experience of the long stops before trying to shorten them.
As a Nitrox Instructor I have to teach the BSAC syllabus, but
when we get to the best bit (what the gas can do for you), I have to ignore or gloss over what to me is one of the main
advantages.
The reduction of deco time by using a richer mix.
No you don't. You explain that Basic and Advanced are progressive steps towards ERD and possibly Trimix. You explain that Nitrox can be used to shorten deco stops but requires further training and experience.
This is the progression I advocate.
1. Get a Basic ticket as soon as your comfortable in the 20s and your breathing rate has stabilised. This will allow you to avoid the risks and tedium of decompression as you progress into the 30s.
2. Get an Advanced ticket when your regularly diving the mid 30s and start hitting the no deco limits. 50% will make deco a lot safer and get you used to gas switches.
3. Get an ERD ticket when the twinset arrives, your used to doing significant deco hangs (30 to 60mins) and you have a feel for the gas use. By this time switches will be second nature and you will have spent so long decompressing that buoyancy control should be a fine art. The ticket allows you to keep the hangs sensible if you want to go deeper and have to lean off the bottom gas O2.
4. Your back to breathing Air and the O2 is still a problem. Go get your Trimix ticket. You have another stage to think about, bailout is different again, the deco profile is even more critical. But you have built the skills progressively over the other courses.
As for the 80%/100% buisness. Far to risky.
BSAC divers cant hold stops, dont you know that?
The Nitrox limits make no theoretical or practical sense, that is why I object to them. The whole stops thing is just a convenient sop (IMO).
But no I don't think we should allow Adv Nx to do accelerated. There are a number of theory and practical issues that I don't think you can ignore.
Regards
Matt
Ok lets go to your wish list.
This is the progression I advocate.
1. Get a Basic ticket as soon as your comfortable in the 20s and your breathing rate has stabilised. This will allow you to avoid the risks and tedium of decompression as you progress into the 30s.
2. Get an Advanced ticket when your regularly diving the mid 30s and start hitting the no deco limits. 50% will make deco a lot safer and get you used to gas switches.
3. Get an ERD ticket when the twinset arrives, your used to doing significant deco hangs (30 to 60mins) and you have a feel for the gas use. By this time switches will be second nature and you will have spent so long decompressing that buoyancy control should be a fine art. The ticket allows you to keep the hangs sensible if you want to go deeper and have to lean off the bottom gas O2.
4. Your back to breathing Air and the O2 is still a problem. Go get your Trimix ticket. You have another stage to think about, bailout is different again, the deco profile is even more critical. But you have built the skills progressively over the other courses.
Yep, sounds good. Natural progression and all that, but none of
it happens in the dive world I inhabit.
The vast majority of twinsetted divers do not go to
stage 3(ERD) before they twin. Rightly or wrongly the current
fad for UK diving is to get Nitrox, backplate/wing and
twins. These guys do it at stage 2 on your list. In fact I'd go
further to say that IMO the vast majority of twinset divers are
not either ERD or trimix.
Why? Because once you get to Advanced Nx + twins it opens up
enough variables to get quite a few years UK diving before you
even need to think about going further.
So lets rework the question.
Is accelerated deco safer/more advantagous and do we really
need another level to teach it (cant it be included in the
Advanced ticket)?
Discuss
TerryH
nick kay
02-10-2003, 09:39
Terry: Could you change Advanced Nitrox to Allow acelerated deco
Matt: BSAC have an accelerated deco course, ERD.
Terry: And it takes three days, is very involved. Costs over ?200 +other expenses and for what? So I can carry a pony/stage with upto 80% in it?
Nick: Sorry, there's more to the ERD course than being able to do accelerated deco.
Nick: Talk to anyone who's been on the course with an Instructor such as Jack Ingle or Graeme Bruce. Ask them what they got out of the course. Most of them will probably say its one of the best courses they've ever been on and they learned a huge amount
:=Matt: Response
:=TerryH: Latest
Matt: Could you change Advanced Nitrox to Allow acelerated deco
Terry: BSAC have an accelerated deco course, ERD.
Matt: And it takes three days, is very involved. Costs over ?200 +other expenses and for what? So I can carry a pony/stage with upto 80% in it?
Nick: Sorry, there's more to the ERD course than being able to do accelerated deco.
Nick: Talk to anyone who's been on the course with an Instructor such as Jack Ingle or Graeme Bruce. Ask them what they got out of the course. Most of them will probably say its one of the best courses they've ever been on and they learned a huge amount
Nick I would like to point out that you have mixed up TerryH's and my view up. I would appreciate it if you would edit the post so that it is accurate.
I am in complete agrgeement with you. More people should be doing ERD courses.
Regards
Matt
Chris Cherrington
02-10-2003, 09:51
The whole BSAC & 100% thing is doing the round over on Club Matters. TerryH made a post about Advanced Nitrox which I think is best discussed here
Yes it is well done!!
3. Get an ERD ticket when the twinset arrives, your used to doing significant deco hangs (30 to 60mins) and you have a feel for the gas use. By this time switches will be second nature and you will have spent so long decompressing that buoyancy control should be a fine art. The ticket allows you to keep the hangs sensible if you want to go deeper and have to lean off the bottom gas O2.
Surely you cannot do deco this long as a BSAC diver? The 88s have a 20 minute max..........
The "fad" for twins and the desire to be a "technical" diver is not just in the UK. This is a phenomenon in the US too. The FO2 in the deco mix only matters if you are really trying to cut time off and as you say Matt most agencies Adv. EAN courses are not deco courses.
I am a bit of a mixed gas anorak so I have been interested in the BSAC Adv EAN as a new joiner and an IANTD diver.
My observation (not critism) is that the ERD is air based and 40m+ Surely trimix is a better bottom gas at this depth? If so then any He-free deco mix is the best solution to "pull" the He out? A rich EAN is the best (get the N2 out too) and I personally do not have a problem with EAN80 - its easier to blend as its hard to get O2 at >200bar.
As we are on the BSAC forum, not Scubaboard or whatever, can we have a general viewpoint on the use of Trimix (with or without 100% O2 deco) in BSAC? I would like to do the new IANTD 40m Trimix but why can't BSAC be at the forefront of this? The commercial view out there in the training schools is to turn their noses up at "entry" level Trimix.
It seems to me that they (money guys) are looking at the ?500 Trimix course as revenue and entry level as a "waste of time". Perhaps too soon to tell? We need to see what happens post-DEMA.
Surely the 'strength' of BSAC should be a non money-making viewpoint?? Ideal for promoting the safe use of mixed gas therefore - INCLUDING 100% O2 to come back to Matt's point (sorry mate went off a bit to He matters).
Chris
neil carter
02-10-2003, 11:01
I would like to do the new IANTD 40m Trimix but why can't BSAC be at the forefront of this?
Why, oh why??
But this in one simple sentence encapsulates what almost all of the "Club Matters" discussions have been about, indeed I seem to remember a separate thread suggesting "Leading From The Front" !!!
If BSAC is the governing body etc etc, then surely part of our remit is to lead from the front, and to be in the forefront of diving evolution.
Let's enable other Agencies qualifications, (they ain't broke, so why do we continually try to fix 'em). Let's enable the inherent PPO2's which come with those qualifications, let's enable other Agencies 100% O2 where applicable, let's enable primary long hose deployment. Then, if we re-write the SDP's to match principles we accept, we should then be able to adjust our third party insurance to match our diving, rather than adjust our diving to match our insurance cover - after all, AIUI - most underwriters only seek to know that diving is undertaken in compliance with the "recommendations" of the diver's training Agency, or am I being too simplistic here?? Then perhaps we could consider moving ahead of the pack, AKA being at the forefront, and enabling Nitrox as the basic gas for entry level diving. Controversial?? Maybe, but then so were Gugen and Small fifty years ago.
Neil Carter
Terry: Could you change Advanced Nitrox to Allow acelerated deco
Matt: BSAC have an accelerated deco course, ERD.
Terry: And it takes three days, is very involved. Costs over ?200 +other expenses and for what? So I can carry a pony/stage with upto 80% in it?
Nick: Sorry, there's more to the ERD course than being able to do accelerated deco.
Nick: Talk to anyone who's been on the course with an Instructor such as Jack Ingle or Graeme Bruce. Ask them what they got out of the course. Most of them will probably say its one of the best courses they've ever been on and they learned a huge amount
I know that the course is good and that you have some very good
and knowlegeable Instructors out there, but thats not much help
if many divers who are using Nx & twinsets have no intention of
doing it.
In my club I have a whole raft of good experienced divers who
would benefit from A.deco, but who wouldnt be going ERD for
years, if ever.
Even if you made the ERD ticket more accessable, I'm not sure
it would make a difference.
We are mainly doing 40-50m dives on weak mixes and going into
deco to extend bottom times. I really dont see any reason why a
DL/Advanced nitrox with 200 UK dives isnt classified as
proficient enough to use a richer mix and shorten those stop
times.
When Nitrox was in its infancy you could argue that such
techniques were advanced. Now we are comtemplating using nitrox
from day one. That IMO means a rethink of what sorts of diving
we do and what we can take from supposed more advance courses
to make life easier and safer.
TerryH
Chris Cherrington
02-10-2003, 12:37
If BSAC is the governing body etc etc, then surely part of our remit is to lead from the front, and to be in the forefront of diving evolution.
BSAC is the UK governing body - it should be definative in terms of UK diving. Most technical agencies are US based I think there are differences in terms of diving conditions - tide vis etc.
Either BSAC is for Scuba-lite (less than 40m no-deco[PADI]) or for all including technical, if the latter then I agree with you 100%.
Let's enable other Agencies qualifications, (they ain't broke, so why do we continually try to fix 'em). Let's enable the inherent PPO2's which come with those qualifications, let's enable other Agencies 100% O2 where applicable, let's enable primary long hose deployment. Then, if we re-write the SDP's to match principles we accept, we should then be able to adjust our third party insurance to match our diving, rather than adjust our diving to match our insurance cover - after all, AIUI - most underwriters only seek to know that diving is undertaken in compliance with the "recommendations" of the diver's training Agency, or am I being too simplistic here?? Then perhaps we could consider moving ahead of the pack, AKA being at the forefront, and enabling Nitrox as the basic gas for entry level diving. Controversial?? Maybe, but then so were Gugen and Small fifty years ago.
Neil Carter
Yep - you're right there too.. (And no you're not being simplistic but intelligent.)
OK everyone else - how do we achieve this?
Chris
OK everyone else - how do we achieve this?
Chris
We need a pressure group with clear defined aims that can
present the issues to the relevant BSAC body.
There is already a list of a over a dozen DO, TO & Inst etc.
who feel that action is needed and I am sure once a formal
proposal is done, many more will also add there voice.
After that its up to BSAC. We go though the accepted BSAC
procedure to allow them a resonable amount of time to discuss
the issues raised.
This is where feedback is so important. True we may not know
the whole picture and there might be other areas we are unaware
of, but unless told we will taylor our response to the picture
we do see.
TerryH
I know that the course is good and that you have some very good
and knowlegeable Instructors out there, but thats not much help
if many divers who are using Nx & twinsets have no intention of
doing it.
Do they need to do it. A twinset of Nitrox is going to get you some very useful bottom time in the mid 30s which accounts for an awful lot of quality diving.
In my club I have a whole raft of good experienced divers who
would benefit from A.deco, but who wouldnt be going ERD for
years, if ever.
If they know they will benefit they should know they need to do the course.
Even if you made the ERD ticket more accessable, I'm not sure
it would make a difference.
We are mainly doing 40-50m dives on weak mixes and going into
deco to extend bottom times.
What, and you haven't realised that this is very serious diving and your training may not be suffucient? Personally one of the main reasons for my doing IANTD Technical Nitrox (ERD) was so that I could get an assessment from someone that really does know what they are doing. To know that you are (or are not) doing things as safe as you possibly can is well worth the money as far as I am concerned. Even if you are as good as you think you are, you will still learn a whole bunch of new stuff to go out and play with. Stop being a tight wad and go do an ERD course.
I really dont see any reason why a
DL/Advanced nitrox with 200 UK dives isnt classified as
proficient enough to use a richer mix and shorten those stop
times.
They are profficient. What they do not have is the knowledge to do it safely. That is what the course is for.
When Nitrox was in its infancy you could argue that such
techniques were advanced. Now we are comtemplating using nitrox
from day one. That IMO means a rethink of what sorts of diving
we do and what we can take from supposed more advance courses
to make life easier and safer.
AFAIC you are showing your lack of knowledge. Accelerated deco is not safer. It introduces a whole new set of risks and problems to manage.
I don't think that the Advanced timetable has the space for either the theory or practical lessons to do these issues justice. Neither do I think that there are that many people who ever get into regular 40 and 50m diving. Lots say they want to, few do, and that is perfectly fine. I have trouble filling the deeper dives even going outside the branch, a fairly common story amongst organisers and skippers AFAIK.
Regards
Matt
Nigel Hewitt
02-10-2003, 20:07
When Nitrox was in its infancy you could argue that such
techniques were advanced. Now we are comtemplating using nitrox
from day one. That IMO means a rethink of what sorts of diving
we do and what we can take from supposed more advance courses
to make life easier and safer.
Must agree. Starting beginners on rich nitroxes and letting them advance 'towards' air as they are more qualified seems eminently sensible. An inadvertent ascent is still bad but not so bad and the SPG will call time long before the no-stop limits. I've just never heard it suggested before.
nigelH
Me agreeing with Terry? Apocalypse looms.
> Starting beginners on rich nitroxes and letting them advance
> 'towards' air as they are more qualified seems eminently
> sensible.
There's one fly in the ointment.
You end up getting someone used to 36% in his bottle when doing 20m or less. Then he qualifies as a SD - suddenly, he's not allowed to use the gases he's used to.
Will this cause a problem? Only if he's a mathematical numpty. And there are many of them around. Is this enough of a reason not to teach OD on nitrox? I don't know...
Vic.
nick kay
03-10-2003, 00:53
Nick I would like to point out that you have mixed up TerryH's and my view up. I would appreciate it if you would edit the post so that it is accurate.
Regards
Matt
Apologies - there were so many :=:= that I got them wrong
:=if many divers who are using Nx & twinsets have no intention of
:=doing it.
Do they need to do it. A twinset of Nitrox is going to get you some very useful bottom time in the mid 30s which accounts for an awful lot of quality diving.
Yep and once you have done a year or two of that diving what
then?
:=In my club I have a whole raft of good experienced divers who
:=would benefit from A.deco, but who wouldnt be going ERD for
:=years, if ever.
If they know they will benefit they should know they need to do the course.
But they dont do they Matt. What they should and what they actually do, is two entiry diffrent things.
I want solutions in the real world not the Matt would like
world.
:=We are mainly doing 40-50m dives on weak mixes and going into
:=deco to extend bottom times.
What, and you haven't realised that this is very serious diving and your training may not be suffucient? Personally one of the main reasons for my doing IANTD Technical Nitrox (ERD) was so that I could get an assessment from someone that really does know what they are doing. To know that you are (or are not) doing things as safe as you possibly can is well worth the money as far as I am concerned. Even if you are as good as you think you are, you will still learn a whole bunch of new stuff to go out and play with. Stop being a tight wad and go do an ERD course.
Sorry Matt that reads like the current DL/Adv + Nx courses
are inadequate for the depth/deco allowed and that ERD would
make it safe. Entry requirement for ERD is Sport + Adv
nitrox. While true there are some diffrent techniques, ERD is
really as you say, to confirm skills not teach them (unless you
are a very new Sport diver). Yes it has advantages, but I would
question the advantage over an experinced DL/Adv who has done a
good many actual dives in exactly the enviroment that they are
certified to do. The one thing that ERD has got is A.deco.
As a Uni club the tight wad bit is, shall we say a bit harsh
(NB: Toned down for Keith).
They are profficient. What they do not have is the knowledge to do it safely. That is what the course is for.
Come on Matt thats a bunch of ******. Take a look at the
syllabus. <a href="http://www.bsac.org/techserv/syllabus/erdsyl.htm" >http://www.bsac.org/techserv/syllabus/erdsyl.htm</a>
With very little exception there is nothing on there that a
well dived, experiencd DL/Nx hasnt done already. True the
mentoring/workshop bits are good and everybody can do with a
bit of revison and for that alone its a good course, but to say
that they dont have the knowledge to do it safely degrades their
cert and there experince.
When Nitrox was in its infancy you could argue that such :=techniques were advanced. Now we are comtemplating using nitrox :=from day one. That IMO means a rethink of what sorts of diving :=we do and what we can take from supposed more advance courses :=to make life easier and safer.
AFAIC you are showing your lack of knowledge. Accelerated deco is not safer. It introduces a whole new set of risks and problems to manage.
And you are being a bit insulting Matt. I am fully aware of the
ramifications of A.deco (I am a Nx Inst. after all) and see no
reason why a profficient and experinced diver couldnt handle
the so called risks/problems involved.
I don't think that the Advanced timetable has the space for either the theory or practical lessons to do these issues justice. Neither do I think that there are that many people who ever get into regular 40 and 50m diving. Lots say they want to, few do, and that is perfectly fine. I have trouble filling the deeper dives even going outside the branch, a fairly common story amongst organisers and skippers AFAIK.
A lot of the theory is already there and adding the ramifications of A.deco wouldnt be that difficult.
Sorry there are no practical diffrences. Adv. Nx has rich mixes
for deco, it's just not A.deco. Same skills doen at the same
time. Only diffrence is following a diffrent table/plan.
These are experinced dievsr we are talking about.
Next time you are on a charter/shuttle boat, ask that twinset
diver if they have done an ERD course and if they regularly go
into deco. The majority awnser will be No and Yes.
The vast majority of decent wrecks in our neck of the woods
are in the 30-40m range. That means twins or 15's to get any
decent time on them and chances are that you will be into or on
the verge of deco even if on a 12.
If we have divers who dont do the ERD course either through
lack of time and/or money and simply go diving, then do we keep
saying "you should do ERD", knowing they wont or do we change/adapt/revise existing courses to make sure that thy have
those best elements?
TerryH
Chris Cherrington
03-10-2003, 15:29
> Starting beginners on rich nitroxes and letting them advance
> 'towards' air as they are more qualified seems eminently
> sensible.
There's one fly in the ointment.
You end up getting someone used to 36% in his bottle when doing 20m or less. Then he qualifies as a SD - suddenly, he's not allowed to use the gases he's used to.
Will this cause a problem? Only if he's a mathematical numpty. And there are many of them around. Is this enough of a reason not to teach OD on nitrox? I don't know...
Vic.
Start them on 32 - why use 36 anyway???? With an MOD of 40 EAN32 is close to the "standard" diving gas within the 35m range for SD. Beyond that it is time to think about Helium...
Chris
(please don't use this to start up the PO2 debate again... Max working depth EAN32 is 33.8m @ 1.4ATA PO2 - for 32-40m diving air is sort of Ok if that's all you're qulified to breathe I suppose).
Dominic Humphries
03-10-2003, 15:56
Accelerated deco is not safer. It introduces a whole new set of risks and problems to manage.
That's one way of looking at it..
On the other hand, is using a rich nitrox mix more dangerous than spending a lot more time in the water? Hypothermia, dehydration, changeable weather conditions, worsening tides as you get further and further from slack, etc. all pose risks for a diver.
I find it hard to believe that the dangers of accelerated deco outweigh the dangers of NOT accelerating your deco.
On the other hand, is using a rich nitrox mix more dangerous than spending a lot more time in the water? Hypothermia, dehydration, changeable weather conditions, worsening tides as you get further and further from slack, etc. all pose risks for a diver.
Yes and absolutely none of them make accelerated deco safer. Why? Because if you choose to accelerate the deco you accept that you may have to do the long stop anyhow. If you are not prepared to do the long stop you are not prepared to accelerate it AFAIC it really is that simple.
I find it hard to believe that the dangers of accelerated deco outweigh the dangers of NOT accelerating your deco.
There is a DCI implication to start with. Accelerated deco will change where the inert happens to be across the tissue spectrum. You immediately assume a risk because no one actually knows what the upshot is in terms of bends incidence. Which is why the ERD courses to one extent or other tell you about what to eat, how to hydrate, etc, etc. Avoiding bends is not just about dissolved gas.
There is the risk of what happens when it goes wrong. If you have 20 mins of back gas stops and have to blow through them you have a very good chance of walking away. If you blow through 20 mins of planned acceleration you are highly likely to be pushed away. This is why the ERD courses have such an emphasis on basic skills, the surface is not a viable option.
The best way I can think to describe Accelerated deco is that it is similar to a dive computer Vs tables. You trade time against conservatism and risk.
Regards
Matt
:=
:=:=if many divers who are using Nx & twinsets have no intention of
:=:=doing it.
:=
:=Do they need to do it. A twinset of Nitrox is going to get you some very useful bottom time in the mid 30s which accounts for an awful lot of quality diving.
:=
Yep and once you have done a year or two of that diving what
then?
Well plenty of people carry on in the mid 30s for the rest of their diving lives. I don't blame them either, to progress further in relative safety requires commitment, time and money.
:=If they know they will benefit they should know they need to do the course.
But they dont do they Matt. What they should and what they actually do, is two entiry diffrent things.
I want solutions in the real world not the Matt would like
world.
Allowing Advance Nx to accelerate will not make the real world any less risky. The deeper you go and the longer you stay the further you are from safety. ERD training reduces risks, much as cave training reduces the risks of overhead.
AFAIC the real world solution is to educate people. If someone is ERD diving they need to be ERD trained.
Sorry Matt that reads like the current DL/Adv + Nx courses
are inadequate for the depth/deco allowed and that ERD would
make it safe.
Then you misunderstand me.
The current DL course, in combination with the adventurous diving SDPs, is adequate for short excursions into the 40 to 50m range. An Adv Nx course will allow you to make the decompression such diving involves, safer.
Nothing short of a submarine is going to make ERD diving safer. There are so many risks and problems to overcome you could say it is inherrently unsafe. To undertake such dives in relative safety is wholly dependant on the divers personal ability. Training and knowledge give you the edge, they improve your chances of getting home undamaged. Accelerated deco is just a tool that makes decompression manageable, it does not make things any safer.
Entry requirement for ERD is Sport + Adv
nitrox. While true there are some diffrent techniques, ERD is
really as you say, to confirm skills not teach them (unless you are a very new Sport diver).
But it does include new skills and approaches. It also examines existing skills in much more detail. There is very little margin for error on ERD dives. Success particularly in the face of a problem, is in the detail.
As a Uni club the tight wad bit is, shall we say a bit harsh
(NB: Toned down for Keith).
OK let me put it frankly. Go get ERD training, the 200 or 300 quid it costs may save your life.
:=They are profficient. What they do not have is the knowledge to do it safely. That is what the course is for.
Come on Matt thats a bunch of ******.
...
that they dont have the knowledge to do it safely degrades their
cert and there experince.
Not at all. Do the course, practice what is taught and then tell me you are not better equipped to undertake ERD dives.
:=When Nitrox was in its infancy you could argue that such :=techniques were advanced. Now we are comtemplating using nitrox :=from day one. That IMO means a rethink of what sorts of diving :=we do and what we can take from supposed more advance courses :=to make life easier and safer.
Nitrox used as a back gas allows deco to be avoided, it makes diving safer. 50% breathed as back gas during decompression to some extent overcomes the limitations of our decompression knowledge, it is conservative.
Accelerated deco does not make anything safer. I can't see it has a place in an Advanced Nitrox course. To assess people on an Advanced Nitrox course to the standard that ERD requires may deny a qualification which is intended to make people safer.
:=AFAIC you are showing your lack of knowledge. Accelerated deco is not safer. It introduces a whole new set of risks and problems to manage.
And you are being a bit insulting Matt.
I am not trying to be, you keep saying Accelerated deco is safer, it isn't!
You will not like this though. I am trying to avoid saying your posts exhibit an arrogance that has no place in ERD diving. You appear to be saying "I can't learn from an ERD course." In fact I think you could learn from the Attitude and Approach modules.
I am fully aware of the ramifications of A.deco (I am a Nx Inst. after all)
Are you? Your initial post suggested acceleration on 50%. Very few ERD trained divers use 50% as a deco mix, its a pretty crap choice.
and see no reason why a profficient and experinced diver couldnt handle the so called risks/problems involved.
I know Ocean Divers that could handle diving to 30m and Sport Divers that could happily do 40m. We do not let them. We encourage them to do further training and we assess them to a higher standard.
:=I don't think that the Advanced timetable has the space for either the theory or practical lessons to do these issues justice.
A lot of the theory is already there and adding the ramifications of A.deco wouldnt be that difficult.
AIUI the BSAC Advanced Nx course is based around using a BSAC 88 Nx table or a single mix dive computer. It does not cover multiple gas dive planning. It does not cover Run Times. It does not cover PPO:PPN gradients. It does not cover the inadequacies in deco theory. It does not cover baleout and contingency planning. It does not cover kit configuration in any sort of detail. It does not even cover using a table which matches your computer for planning and baleout. Those are the things I came up with in 30 seconds.
Next time you are on a charter/shuttle boat, ask that twinset
diver if they have done an ERD course and if they regularly go
into deco. The majority awnser will be No and Yes.
I find very few people willing to do more than 10 or 15 mins of deco.
The vast majority of decent wrecks in our neck of the woods
are in the 30-40m range. That means twins or 15's to get any
decent time on them and chances are that you will be into or on
the verge of deco even if on a 12.
I am of course in the same neck of the woods.
35m 30mins 30% is about 12mins of stops. I wouldn't bother accelerating that, the stop time would become too short to rely on the acceleration working.
If we have divers who dont do the ERD course either through
lack of time and/or money and simply go diving, then do we keep
saying "you should do ERD", knowing they wont or do we change/adapt/revise existing courses to make sure that thy have
those best elements?
Accelerated deco only makes sense when you are into significant stops (25+ mins). If people are doing those sorts of dives they should recognise the risks they are taking and get further training. If they do not recognise the risks then they REALLY should get ERD training.
If your suggesting we need a twinset skills course then I agree.
Terry I don't suppose we are going to agree on this one. I am fairly evangelical about the benefits of ERD training. It's ironic that I am also evangelical about Sport Divers getting on IFCs as soon as possible, now where did I get that from?
Anyhow if you are worried about the cost think of it like this. With an ERD ticket you could do all your diving on air + 80% thus avoiding expensive Nx twinset fills and O2 cleaning. You would recoup the cost in a year or two. So go do the course, you might learn something. I expect that having done the course you will be encouraging others to follow rather than asking BSAC to enable accelerated for Advanced Nx.
Regards
Matt
Apolgies for the late reply Matt been away.
Before accusing me of Ignorance and Arrogance, lets look again
at what I am saying.
We hav'nt got the statistical facts, but based on the number of
ERD courses available + anecdotal evidence, it's pretty obvious
that the uptake of DL and above doing ERD is pretty slim. We
both know that on average most twinsetted divers are not ERD
trained.
So you can keep saying ad-nauseum that you should do ERD, but
the reality is they dont. So what do you do?
You can keep bleating on about it or look at ways around it.
If we accept the principle that elements of all so called
advanced courses will eventually become mainstream, then
surely at some point elements of ERD will be moved over to
Advanced Nitrox etc.
At what point will Basic Nitrox be part of Sport Diver or
Advanced included as part of DL? It will happen it's just a
question of when. In the meantime we have divers who ARE doing
30-50m dives going into serious deco and do not do ERD.
I advocate looking at A.Deco to make stops shorter and I say
safer. You say that it's not safer because they havnt done an
ERD course and they havnt got the
skills/experience/mindset/smarts to do it.
Hmm isnt that beeing a bit arrogant to make such assumptions?
Basic choice. I can go on a BSAC ERD course costing ?200+
or I can go and get a good 4-5 days hardboat diving instead.
Guess what the vast majority choose?
ERD is a good course no argument, but unless you can make it
more accessable, then the best I can hope for is to facilitate
bringing selective elements into mainstream.
After all are you telling me A.Deco suddenly becomes safer once
I fix an ERD sticker in my book?
Either it is or isnt. The rest is just logistics.
TerryH
We hav'nt got the statistical facts, but based on the number of
ERD courses available + anecdotal evidence, it's pretty obvious
that the uptake of DL and above doing ERD is pretty slim. We
both know that on average most twinsetted divers are not ERD
trained.
So you can keep saying ad-nauseum that you should do ERD, but
the reality is they dont. So what do you do?
I also keep saying ad-nauseum that the vast majority of DLs and twinset divers are neither doing or are interested in ERD diving.
You can keep bleating on about it or look at ways around it.
If we accept the principle that elements of all so called
advanced courses will eventually become mainstream, then
surely at some point elements of ERD will be moved over to
Advanced Nitrox etc.
At what point will Basic Nitrox be part of Sport Diver or
Advanced included as part of DL? It will happen it's just a
question of when.
Like I say, Basic and Advanced Nx make traditional diving practices safer, they reduce risks. What we know as ERD is a collection of techniques to manage the risks associated with dives beyond traditional limits. By taking on ERD dives you dive at increased risk. Hence I believe the aims of Advanced Nitrox and ERD are incompatible.
In the meantime we have divers who ARE doing
30-50m dives going into serious deco and do not do ERD.
I would not consider 5 to 15 mins at 6m as an ERD dive. As a guide the maximum combined stop time on 88s is 20 mins. When deco exceeds that 20 mins it is fair to say you are ERD diving. But that is only a small minority of twinset divers. Further, although the takeup of BSACs ERD qualification is pretty depressing Normoxic trimix courses are very much on the rise. Only a minority of those that qualify use Trimix regularly. It would appear that those who are interested in ERD are in fact spending more money on extra training.
I advocate looking at A.Deco to make stops shorter and I say
safer. You say that it's not safer because they havnt done an
ERD course and they havnt got the
skills/experience/mindset/smarts to do it.
No, you still misunderstand me. Accelerated deco increases risks, you can not escape that fact. The ERD course enables you to identify and mitigate the risks involved with ERD dives and assesses your ability to do so. Nothing you learn on an ERD course will make such dives safer, you have to do that yourself, using the techniques and guidance that the course teaches.
Hmm isnt that beeing a bit arrogant to make such assumptions?
I have at least completed an ERD course and have several hundred accelerated deco dives under my belt. Does that not put me in a better positioned from which to make an assessment?
BTW What would you say to a OD who wants to do a 30m dive or a SD that wants to do a 40m?
Basic choice. I can go on a BSAC ERD course costing ?200+
or I can go and get a good 4-5 days hardboat diving instead.
Guess what the vast majority choose?
The vast majority choose not to do ERD dives. Those that are interested in ERD appear to be more inclined to spend ?100 to ?300 extra on courses which are argueably more complete than the BSAC offering.
ERD is a good course no argument, but unless you can make it
more accessable, then the best I can hope for is to facilitate
bringing selective elements into mainstream.
On which I agree. What about the suggestion for a short, branch delivered twinset course?
After all are you telling me A.Deco suddenly becomes safer once I fix an ERD sticker in my book?
No. Accelerated deco does not become safer...you do, same as doing a SD, DL or AD course. The water remains the same, only your ability changes.
BTW we are getting circular.
Regards
Matt
David Humm
09-10-2003, 01:45
Call me a Numpty but, may I clarify ?
Is this thread specifically discussing the merits/needs for divers undertaking what BSAC 'Guidelines' or 'recommendations' determine and ERD - Without having completed the appropriate ERD course...
or
Is it also being used to indirectly, having a 'pop' at divers like myself who see fit to use "twinsets backplates and wings" in a so called fad ?
Far be it for me to digress from the primary issue of this thread but a few posts border on arrogance. I use said 'fad' equipment because of it's increased safety benefits as a purely recreational diver. I'm a nitrox qualified user and use it, well, for the right reasons.
Just wanted to point out that there are twin users who don't (and prolly won't ever) consider themselves Technical Divers. They (like me) want additional safety.
Kind regards
Dave
Chris Cherrington
09-10-2003, 10:31
Call me a Numpty but, may I clarify ?
Is this thread specifically discussing the merits/needs for divers undertaking what BSAC 'Guidelines' or 'recommendations' determine and ERD - Without having completed the appropriate ERD course...
No it started way back with the 100% O2 debate...
or
Is it also being used to indirectly, having a 'pop' at divers like myself who see fit to use "twinsets backplates and wings" in a so called fad ?
Far be it for me to digress from the primary issue of this thread but a few posts border on arrogance. I use said 'fad' equipment because of it's increased safety benefits as a purely recreational diver. I'm a nitrox qualified user and use it, well, for the right reasons.
Just wanted to point out that there are twin users who don't (and prolly won't ever) consider themselves Technical Divers. They (like me) want additional safety.
Kind regards
Dave
There is a "fad" for 'technical' stuff in the UK. As far as the specific of twins is concerned the extra redundancy gives additional safety, but you do need to be familiar with this configuration. Because most of us are taught with single tank and octo rigs many divers are not familiar with twins. Many also do not follow the correct drill in breathing one tank down to 1/3 (or whatever) then swapping.
Dave, I'm sure you are a safe diver, but some people treat twins as a sort of fashion statement and I think those people are less safe than in the kit they were trained in.
The best diver as far as I am concerned is one who is correctly kitted for the dive they are making. A 10m dive for 30 mins is fine on a single 7L tank. There is an issue with twins as to whether to use them all the time to be familiar with them. If you would like to debate that start a new thread, I'm sure there are plenty of views about that - I'm firmly on the fence on that one..
Chris
Call me a Numpty but, may I clarify ?
Is this thread specifically discussing the merits/needs for divers undertaking what BSAC 'Guidelines' or 'recommendations' determine and ERD - Without having completed the appropriate ERD course...
The thread originated with the proposal to allow suitably trained divers to use 100% and 1.6 bar PPO within BSAC. Personally I think that is a very good idea.
TerryH further proposed that BSAC Advanced Nx divers should be allowed to accelerate deco. I think that is a very bad idea. To summarise why, I think that the step from Basic Nitrox to accelerated deco is too big for a single course.
or
Is it also being used to indirectly, having a 'pop' at divers like myself who see fit to use "twinsets backplates and wings" in a so called fad ?
Not me.
Far be it for me to digress from the primary issue of this thread but a few posts border on arrogance. I use said 'fad' equipment because of it's increased safety benefits as a purely recreational diver. I'm a nitrox qualified user and use it, well, for the right reasons.
If your regularly diving below 30m a twinset is a sensible upgrade. You only become victim to the fad if you fail to learn how to use it, or as Chris Cherrington says, you have no reason to use it. To borrow a phrase from skiing 'All the gear and no idea'
Just wanted to point out that there are twin users who don't (and prolly won't ever) consider themselves Technical Divers. They (like me) want additional safety.
OK I hate the term 'Tachnical diver' I don't think it means anything anymore. But I completely agree with your point.
Considering both what Terry and Chris are saying, I can see a benefit in breaking the Twinset and Config stuff out of the ERD and into a short SDC. As Terry says people are using twinsets but do not see the ERD as suitable for what they want to do. As Chris says there are people using twinsets with no real idea of how and why. Possibly not surprising as we do not have a twinset specific course other than ERD.
What do you think Dave? Would a one day Twinset SDC appeal to you?
Regards
Matt
Dominic Humphries
09-10-2003, 12:30
Many also do not follow the correct drill in breathing one tank down to 1/3 (or whatever) then swapping.
Maybe that's because most of us have manifolds and leave them open during the dive..?
:o)
> I can see a benefit in breaking the Twinset and Config stuff
> out of the ERD and into a short SDC.
I can see the benefit, but it's not without problems too...
Just as soon as you introduce a course for something, someone will decide that the course becomes an *essential* requirement; I've already heard of at least one club mooting the banning of twinsets to those without some ticket or other (thankfully, that got roundly defeated at the AGM).
Twinsets aren't rocket-science - they just require a little transfer of knowledge. Most people could work it out for themselves - particularly if given some reading material. Perhaps this is a job for MembersOnly? ;-)
Keeping this sort of thing informal would IMHO be the best bet; a SDC would beat waiting until ERD, but a pint at the bar is perhaps the best training situation for this sort of thing...
Vic.
Twinsets aren't rocket-science - they just require a little transfer of knowledge. Most people could work it out for themselves - particularly if given some reading material. Perhaps this is a job for MembersOnly? ;-)
Perhaps. But I do not think it would be as useful as physically looking at someones kit and questioning why they are doing things the way they do. It also does not adress the practical skills. Unfortunately I think there are quite a few people out there that know they should be doing shut down practice and cylinder switches but don't get around to it, possibly because no one has shown them how.
Keeping this sort of thing informal would IMHO be the best bet; a SDC would beat waiting until ERD, but a pint at the bar is perhaps the best training situation for this sort of thing...
The pint at the bar method is fine if you have an experienced twinset diver available to ask...and he has permission to drink beer;-) Even then you can't guarantee your going to get unbiased consistant or even sensible advice.
Personally I just don't see it as a very efficient way to teach. I already have a 'twinset fettling day' in the pipeline for the half dozen that picked up twinsets this year. It would be easier if I had a syllabus to start from.
Chris Cherrington
09-10-2003, 14:16
:=Many also do not follow the correct drill in breathing one tank down to 1/3 (or whatever) then swapping.
Maybe that's because most of us have manifolds and leave them open during the dive..?
:o)
Then you have, in effect, one big tank? Where is the safety aspect therefore?
Chris
Chris Cherrington
09-10-2003, 14:21
Personally I just don't see it as a very efficient way to teach. I already have a 'twinset fettling day' in the pipeline for the half dozen that picked up twinsets this year. It would be easier if I had a syllabus to start from.
Most "technical" dive shops offer such a course, but I have yet to see one offered by the agencies - IANTD etc. Maybe GUE do a DIR thing, not sure. (Covered in DIR-F to some extent).
Another opportunity for BSAC to "lead from the front"??
Chris
:=:=Many also do not follow the correct drill in breathing one tank down to 1/3 (or whatever) then swapping.
:=
:=Maybe that's because most of us have manifolds and leave them open during the dive..?
:=:o)
Then you have, in effect, one big tank? Where is the safety aspect therefore?
Shut down drills
Manifold has three valves which enables you to isolate the bit that is causing problems
Then you have, in effect, one big tank? Where is the safety aspect therefore?
There is an isolation valve in the the manifold. You shut the manifold and you have 1/2 of that big tank available. You closedown the faulty side then reopen the manifold and you have access to all the gas you are carrying. It relies on remembering to switch regs and being able to shut the manifold down quickly while 1/2 of what is in the big tank is enough to surface on.
Chris Cherrington
09-10-2003, 14:50
:=Then you have, in effect, one big tank? Where is the safety aspect therefore?
There is an isolation valve in the the manifold. You shut the manifold and you have 1/2 of that big tank available. You closedown the faulty side then reopen the manifold and you have access to all the gas you are carrying. It relies on remembering to switch regs and being able to shut the manifold down quickly while 1/2 of what is in the big tank is enough to surface on.
Point taken Pete and Matt.
These I think are skills that should be taught - preferably in a pool and practiced. This really just underlines what has been said in the last few postings. Twins can be safer, or more dangerous, according to training. We seem to be in agreement!
Chris
AndyCarroll
09-10-2003, 19:18
Hi
Doesn't the new BSAC Advanced Diver cover twinsets?
The lecture definitely does. Perhaps its a case of encouraging divers interested in twinsets to progress to advanced diver.
Andy
Hi
Doesn't the new BSAC Advanced Diver cover twinsets?
The lecture definitely does. Perhaps its a case of encouraging divers interested in twinsets to progress to advanced diver.
Actually the theory is in Sport Diver lecture 5
andycarroll
10-10-2003, 12:43
Hi
Thanks, forgot about that one. Although there is a lecture in the new AD which focusses on advanced kit config as well, so, if you have a well prepared instructor, the standard BSAC diver grades can accomodate twinsets.
Andy
vBulletin v3.5.4, Copyright ©2000-2012, Jelsoft Enterprises Ltd.