Does defining "technical diving" serve any purpose?

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I was not typing about computer failure; I was typing about completing a decompression dive within the proper schedule of the computer and being bent.

However, if the computer failed on a dive...and that caused the 'untrained' diver to get hurt.. there'd be room for legal debate I am sure. That said, the existence and availability of proper training creates a situation where the diver is 'expected' to have the skills and resources to survive such an event. What hurt them wasn't the computer failure - it was the failure to cater for that contingency.

Suunto Viper pdf Manual; page 6 & 7 ...

WARNING!
ONLY DIVERS TRAINED IN THE PROPER USE OF SCUBA EQUIPMENT
SHOULD USE THE DIVE COMPUTER! No dive computer can replace the
need for proper dive training. Insufficient or improper training may cause
diver to commit errors that may lead to serious injury or death.
WARNING!
NOT FOR PROFESSIONAL USE! SUUNTO dive computers are intended
for recreational use only. The demands of commercial or professional diving
often expose the diver to depths and prolonged exposures including
multiday exposures that tend to increase the risk of decompression sickness.
Therefore, SUUNTO specifically recommends that the device be not
used for commercial or other severe diving activity.
WARNING!
PERFORM PRECHECKS! Always activate and check the device before
diving in order to ensure that all LCD segments are completely displayed,
that the device has not run out of battery power, and that the oxygen,
altitude and personal adjustments are correct.


WARNING!
NO PROCEDURE, DIVE COMPUTER OR DIVE TABLE WILL PREVENT
THE POSSIBILITY OF DECOMPRESSION SICKNESS (DCS) OR OXYGEN
TOXICITY! You must understand and accept that there is no procedure,
dive computer or dive table that will totally prevent the possibility of a
decompression accident or that oxygen toxicity will not occur, even within
accepted limits. For example, the individual physiological make up can vary
within an individual from day to day. The dive computer cannot account for
these variations. As an added measure of safety, you should consult a
physician regarding your fitness before diving with the dive computer.
Decompression sickness can cause serious injury or death.
DIVING WITH ENRICHED AIR MIXTURES (NITROX) EXPOSES THE USER
TO RISKS DIFFERENT FROM THOSE ASSOCIATED WITH DIVING WITH
STANDARD AIR. THESE RISKS ARE NOT OBVIOUS AND REQUIRE
TRAINING TO UNDERSTAND AND AVOID. RISKS INCLUDE POSSIBLE
SERIOUS INJURY OR DEATH.
DO NOT ATTEMPT TO DIVE WITH ANY GAS MIX OTHER THAN STANDARD
AIR WITHOUT FIRST RECEIVING CERTIFIED TRAINING IN THIS
SPECIALTY.
WARNING!
USE BACK-UP INSTRUMENTS! Make sure that you use back-up instrumentation
including a depth gauge, submersible pressure gauge, timer or
watch, and have access to decompression tables whenever diving with the
dive computer.

At no point in that pdf Manual is a disclaimer worded reciprocally to "agency" recreational diver limits; it mentions proper training, but does not define "proper training". When I train for 2.5 mile (or longer) rough water swimming competitions, for which the event organizers "require" special insurance, there is no "agency" but I am considered to have "proper training".

Alternatively, just add a disclaimer to their manuals (that reciprocated the advice given by agencies on computers):

i.e. "Users should always dive within the limits recommended by their respective training agencies."

 
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Actually Devon Diver had a descent definition for what constitute technical diving. (We all agree there is always some type of ceiling but Andy was referring to more than a slow ascent.)

I also think we all kind of agree on what constitutes recreational diving as regards limits.

So executing obvious technical type dives without appropriate training and gear is neither but another class of diving, eg. Darwinian Diving. So a diver who exceeds his training / experience diving limits for whatever reason has entered into Murphy's territory.

As far as rebreather diving is concerned it would be more a consideration of what the diver does with it. It is just another piece of equipment, which like open water equipment requires more training.

Dale
 
Saw this thread over the weekend & been meaning to contribute...

Hi Mark,

That's an accurate observation...but.. it's really comparing apples with oranges. The key distinction being who the tables were designed to serve. PADI focus on the concept of the NDL because they understand that the scope of their training system needs to be balanced by always permitting their divers to have direct access to the surface. NDL is just a conceptual way of admitting that their training system is limited. Thus, their trained divers are limited. Navy tables were designed for divers who are subjected to a training system of much broader scope.

This is the case today, but we need to be a bit cautious in generalizing, as there had been some versions of the PADI tables over the years that included deco stops too. Here's mine.

John did an excellent job of concisely summarizing the difference between the Navy tables and the PADI tables.

Agreed. The only thing that I saw that resulted in some confusion was that the NDL's and Residual Nitrogen Group letters for the tables are based upon what "M-values" were selected for the various compartments and which compartment functionally ended up being the "Controlling" one for a particular profile.

There's also a fine art of 'fudging' present within all Tables, since all of their dives (including repetitive dives) are eventually boiled down to a single letter designation that has to try to represent 'all' compartments...both the one that is ultimately controlling a particular profile as well as those that might accumulate enough to be an issue on a subsequent dive - - this is really more of where the 60 vs 120 minute compartment as a factor comes into play.

However, modern technology is throwing a spanner in the works of that well-balanced system. Specifically - the evolution and popularity of diving computers.

True, but in counterpoint, dive computers allow for all compartments in the model to be continuously tracked - - to apply the Tables paradigm, it would be that the computer calculates the 6 (or 16) individual letters for each individual compartment, and then tells you which one is the worst off (eg, "Controlling"). BTW, alluding back to the M-values, it is pretty trivial to make a dive computer more conservative, simply by reducing the max value of all of the M-values by some percentage or fixed value.

For a given ambient pressure, an M-value is defined as the maximum value of inert gas pressure (absolute) that a hypothetical "tissue" compartment can "tolerate" without presenting overt symptoms of decompression sickness (DCS).

However, the limitations of the training remain. The training system assumes that divers will dive short, shallow profiles and not require staged ascents - and that's what it prepares them for. Basic training for basic diving. That diving was named 'recreational'.

That's what it is today.

Agency 'rules' weren't needed before the advent of dive computers - reliance on using the provided tables served to enforce those boundaries. All that PADI can do now is provide recommendations about the limitations that divers should adhere to.

mmmm....this is starting to sound like we are trying to blame dive computers for non-recreational diving.

We can see that there is an obvious 'disconnect' between the principles and concept of training and the potential practices of modern leisure divers. Is it any wonder that some experienced divers criticise that training as being 'inadequate' for the tasks of keeping divers safe?
Is it a failure of the training, or a failure of the divers to understand the limits of that training?

To be honest, I don't think it matters what method a diver uses to calculate their dives; PADI tables, Navy tables, laptop software or dive computers with X, Y or Z algorithm.

WHAT MATTERS is that they recognise the concept of their training and understand what circumstances that training is designed to prepare them for. Training dictates diving boundaries - not the method of calculating nitrogen saturation. The tail shouldn't wag the dog. The tools shouldn't dictate the work.

Some divers argue that people should use their dive computers to exceed the recommended limits of their training program. To me, that's like arguing that motorists should drive their cars to the maximum obtainable speed - that speed limit should be dictated by the capability of the vehicle, not the capability of the driver. Motorists do training that provides capacity to drive under certain -limited- conditions. Their safety is ensured by the imposition of limits. Buying a Ferrari doesn't make you a better driver. Buying a Dive Computer doesn't make you a better scuba diver.

Where the capability of the tool exceeds the capability of the user - then artificial boundaries need to be imposed. This is a situation we now see in recreational scuba diving.

The simple fact is... if a diver wants to do decompression or deep dives... then they need to do appropriate training. PADI and similar agencies don't provide appropriate training for that... they have boundaries. But, they did create the concept of 'technical diving', to allow those boundaries to be extended. The training, standards and demands of that training are, in no way, similar to that provided for recreational diving. It may be provided by the same agency, but it is a totally different concept.

Do we need to define "technical diving"... from a training/limitations perspective..of course we do. It's a totally separate entity to recreational diving. It is based on different concepts, requires different training...and has different limitations. It uses different models for off-gassing. It uses different equipment. It has different procedures. It has different dangers. It has different boundaries.

Diving is diving. You go underwater... you saturate nitrogen, you come up, you de-saturate. Every dive is 'decompression'. Simple. That's an over-arching definition of what we do. However, it can't be an over-arching definition of how we approach it...or how we train to do it. THAT is where the definitions of recreational and technical come into play.

Some good points here; I'll comment on them in aggregate summary later on.



PADI's real goal in making the tables was to reduce the surface intervals between dives so that divers could get in two dives in a dive day without waiting forever. The Navy tables with the 120 minute tissue controlling the surface interval are much longer, leaving divers out of the water sitting on the boat (or wherever) much longer than necessary. Navy divers more frequently do one very long dive and call it a day. PADI intentionally made their first dive limits slightly more conservative than the Navy limits to help reach this goal. Another way to achieve that was to have many more pressure groups in order to decrease the amount of rounding off necessary for calculating the surface interval.

Agreed. And the motivation for them to do this was because recreational diving had become a business, and a longer Surface Interval costs time and time is money, a shorter SI lowered their business expenses and made them more profitable.



As for the original question about defining techincal diving; No, I don't think it serves any usefull purpose.

I'd say that it has limited utility, for several of the reasons you point out:

Some dives will certainly be "tech" and some will certainly be "rec", but there are just too many shaded areas for me to draw a distinct line between them. Limited wreck penetration, cavern diving, throwing on a cf40 of oxygen for a little padding on the last day of your red sea liveaboard. Icediving for example is most certainly overhead diving, but for some reason I have never heard anyone refer to it as "Tech":confused:


I can recall a similar philisophical question many years ago that was discussing what an "Overhead Environment" was. We could easily agree that a 100ft long swim-through was, as was also as a 90ft tunnel ... and 80ft ... and 50ft ... even 10ft ... but if we allowed an interpretation of it being any restriction that prohibited an immediate direct ascent, then even those 1 inch wide hula-hoops that Rec divers were being encouraged to swim through for practicing buoyancy control at some dive resorts ... technically had to count as an "Overhead", which is simultaneouslyl pedantically correct, yet nevertheless utterly absurd. And that's the problems with definitions: we end up with WXY footnotes and the like.

Of course, this also doesn't mean that there's zero value in having a "Not-Rec" tag, be it "Tech" or "Cave" or something else: much of its utility is merely to serve as a warning flag to clearly identify those diving situations that are clearly higher risk than the benign environment - - and all of the simplifying limitations - - appropriate for today's very simple Rec OW-I trained customer.

I'm of two schools of thought on this, though: from a Diving Community perspective, I don't really believe that naming a segment of diving really has all that much value, since risk is risk and it is a continuous gradient. However, there are areas - - cave is the classical example - - where self-regulation for increased training has had a huge impact in reducing dive deaths. But even here, the real observation is that the risks simply ramped up a lot faster - - there isn't necessarily a discontinuity.

Similarly, my OW training many moons ago included the procedures for staged decompression ... as such, I'm quite inclinded to consider deco (particularly "Light" deco) to be well within the recreational realm, at least for what "Rec" meant when I was first introduced to it. For what OW divers are getting taught today, I'm not so sure, though: I can recall diving with an elderly couple a few years ago where the wife nearly flipped out when her computer went into Deco mode towards the end of a dive - - it was first time that she had ever seen it do that.

And the more we learn - - - how about 50 minutes at 100fsw without any deco stops? As per some USN research from a risk-based model from a decade or so ago, that profile only produces DCS symptoms roughly 5% of the time. Frankly, I can see where such knowledge is a double-edged sword because on the one hand there will be those that are risk takers who will abuse the model - - but in counterpoint, if I just did that same profile and was on my deco hang when another diver has a bad emergency, I can be pretty confident that I can abort my deco plans without too much DCS risk and perhaps let that other diver's life be saved ... that's a different trade-off.

Overall, it is simplistically easy to say "Education is the Answer" and suggest that all divers become more knowledgeable as to what's going on inside their bodies. However, such knowledge has overwelmingly been washed out of OW training, presumably on a rationale that it will "scare off" customers, which lets us see where the motivational factors really reside. Diving is an industry afterall, which means that there needs to be viable business models...and one of those business models has indeed been with the identification of "Tech" as a discrete segment and speciality, because the Industry has learned that Tech diver customers spend more money. As such, regardless of what we as divers believe is appropriate for the diving community, there is also this financial incentive within the industry to have the "Tech" label present.



-hh
 
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Those are not "PADI" tables, those are USN tables that PADI printed before they developed their own model and tables.
 
Actually, my description of the difference between the Navy and PADI tables was not quite accurate, as I realized after posting it (with the help of another post and a friendly PM). Different compartments control the dive at different points; the 60 minute compartment (PADI) and 120 minute compartment (Navy) are where the surface intervals are determined. However, the is still true: dives within the limits of the PADI RDP are such that the surface intervals can be governed by the 60 minute compartment, and if a diver exceeds those limits, that is no longer true. That is why the emergency decompression procedures for the RDP are so punitive. If you exceed the limits and want to continue to use the table, you have to wash out first.
 
Those are not "PADI" tables, those are USN tables that PADI printed before they developed their own model and tables.


True, but they were still what was used in OW-I training back in the day.

As such, my point is that the definition of "Rec" diving did used to include decompression, even though today it does not, is thus illustrated.



-hh
 
True, but they were still what was used in OW-I training back in the day.

As such, my point is that the definition of "Rec" diving did used to include decompression, even though today it does not, is thus illustrated.



-hh
... and the definition of "Rec" diving did used to include being able to work tables, and control your buoyancy, and a whole passel of other things that it no longer includes.
 
... and the definition of "Rec" diving did used to include being able to work tables, and control your buoyancy, and a whole passel of other things that it no longer includes.

True... and for me, this seems like the crux of why we are having this debate at all.

People who learnt to dive prior to the mid-late 90's did so in a community that still regarded tech as a 'dark art' for the minority. Dive computers and nitrox were still 'novel' for the majority. Training courses were more comprehensive and more focused upon diver capability and mindset. Peer review was an important factor in determining progression and suitability. Not quite the 'old and bold' mentality of pre-80's divers, but nonetheless subject to an element of social Darwinism that ensured dove responsibly and maintained their own safety.

That isn't the case now. The majority of current generation of McDivers "got their PADI" on holiday, rely on divemasters and electronic aids to provide safety and need to be told what they can and cannot do based upon whatever piece of plastic they have in their wallet. I don't mean that as an insult - it's just a general trait of the modern generation and, from a diving perspective, it is heavily shaped and exploited by the nature of the agencies and McInstructors that provide most of the recreational diving qualifications.

Technical diving isn't a 'dark art' any more. People now "get their PADI tech" on holiday. However, for now at least, that tech training is provided by an older generation of divers who still encompass the ethos of personal responsibility, risk awareness and the concept of a capability-boundary relationship. Technical diving is still an arena where peer review forms an important factor in determining progression and suitability.

In 1990, your 'recreational' dive instructor was probably a grizzled sea-dog, perhaps ex-military, logged in excess of 2000 dives and probably dove deep ship wrecks on their days off. They kinda 'fell into being an instructor' after many years of diving. Those instructors knew divers who died. They'd seen their friends get bent, or been bent themselves. They probably started out by making their own kit, or at least customising and tailoring it for their requirements. They wore a dive watch..and kept tables in their wetsuit pocket. They applied personal standards to the dive courses they taught and treated every student like a new member to an exclusive community.

In 2010, your 'recreational' dive instructor is probably a twenty-something former gap-year student gone adrift, logged a few hundred shallow dives..and was planning to be an instructor before they finished their AOW course. They probably spend their time off chasing tourists of the opposite sex and dancing to euro-pop in a beach bar. The only people they knew who died are their grandparents... in bed. To them, 'the bends' is a scary camp-fire story you tell students about to make them buy a deep or nitrox course. They buy the latest kit, with the latest gadgets, because they'll earn commission from students who want to emulate them. They wear a flashy dive computer, because it helps them get laid in the beach bar after work. They know what their agency standards are and 'try' to apply them most of the time.. but sometimes they just aren't convenient. They treat every student like another pay-cheque... unless they think there's chance for a leg-over.

However....In 2010, your 'technical' dive instructor is probably a grizzled sea-dog, perhaps ex-military, logged in excess of 2000 dives and probably dives deep ship wrecks or caves on their days off. They kinda 'fell into being a tech instructor' after many years of demanding technical diving. They know divers who died. They've seen their friends get bent, or been bent themselves. They probably started out by making their own tech kit, or at least customising and tailoring it for their requirements. They wear a dive watch..and kept tables in their wetsuit pocket. They applied personal standards to the dive courses they teach and treat every student like a new member to an exclusive community.

You see what I am getting at?

Tec is the new Rec baby!

In short - times change. Recreational diving isn't what it used to be - the baton for those standards has now been passed to the tech community. Advocating X, Y or Z diving practices for the current generation, based on experiences from the previous generation, is ignorant of evolution.

Instead of saying "I did this in the 90's and you should do that now also".... I'd argue we should be saying "I did this in the 90's, but to get the same now, you need to look towards the tech community".
 
Well put.

As far as I'm concerned, I'm a couple of generations back from your "grizzled sea-dog" of the 1990's. I made my first dive in 1956, was doing underwater research at Pt. Lobos in the mid 1960s, fell in with Jud Vandervere, the sea otter expert, and through him the Cousteau crowd when they were shooting their sea otter special and my life's path was set. I started teaching in the late 1960s, was never in the military, though somewhat grizzled now, I was not then and was never really what you'd call a "sea dog." Sailboat racer, surfer, ocean swimmer, beach lifeguard, sea plane pilot, diver, sure ... but no tug boats, gotta be bosun on a tug to be a real "sea dog." I'd logged way in excess of 2000 dives, rarely dove deep ship wrecks, but you couldn't keep me out of the kelp forests.

You're right, I kinda 'fell into being an instructor' after perhaps fifteen years of diving. It was not until I got involved with aquaCorps that any divers I knew personally died under the water. I've never been bent and I know very few people who have been. I still make my own wetsuits, I only wear a dive watch when I go to a party 'cause my cellphone keeps excellent time. There is always a set of tables in my pouch. I not only applied my personal standards to the dive courses I taught, I wrote the standards for NAUI, some of which are still in effect, and yes, every one of my students is a new member in a very exclusive community.

I say, "I did this in the 60's, and 70s, and 80s, and 90s and I'm still doin' it, and you know what? It still works." It does not require black gear, or blue gloves, or blue H's or regulators deployed on strangulation straps ... that's all horse $hit. What it takes is a willingness to train, to learn, to practice, to grow and to share. Most of what I see from most of the instructors of today, rec or tech, doesn't particularly impress me ... many (mostly rec) look like students who have not yet finished the course, most of the rest (tec) look like dressage riders faced with a cuttin' pony and a lasso.

What I'm impressed by are those instructors who are starting to "discover" many of the things we always did and who are adopting such things, like teaching up off the bottom ... though there are moments when I feel like what I think an American Indian watching the Europeans "discover" the Western Hemisphere must have felt.
 
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Good posts by DevonDiver and Thal:

I was first certified in 1971 in San Diego. First cert was a very complete NASDS course from San Diego Divers Supply. The SDDS crew were often former Navy Seals and the store was also the training location for NASDS instructors. I was then very fortunate to take a class taught by Lou Fead. Lou was teaching out of Chuck Nicklin's DIVING LOCKER in Pacific Beach. Both courses centered on divers being able to manage various situations and not be equipment dependent. We had no secondary regs, some had no pressure gauges, a few were using the Nemrod BC's. We were learning to be self sufficient in open water. Take what you need for that dive.

Today the "Tech" diver seems geared up for a space expedition even when they are diving at relatively benign dive sites. I see it here in Northern California when I dive Pt. Lobos or Breakwater, and in Seattle @ Edmonds U/W park and Cove 2.

Interesting evolution. I'm with Lou Fead the original "Easy Diver"
 

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