80 replies to this topic

[WreckWench]

3rd reply and we're onto sex. Woohoo!

Ahem....I was ONLY talking about diving young lady!!!

Can I help it that the sport has so many uh...graphic names????

[Diverbrian]

Just in the same way that every dive is a "deco dive", every dive is technical.   It's only a question of degree.  Many people think that something changes once you pass 100', and even more so for 130', and so long as you don't go beyond it everything's OK.  But neglect your gas management at 100' and you'll be in for a nasty shock, not much different from another diver doing the same at 150'.  What's the farthest you could imagine swimming up on one breath?

In some ways the buddy system, as it is usually taught, encourages dependency and complacency.  Tech training above all teaches self-dependency, which has to be good at any depth.  If you see your buddy as someone to look after and help in times of trouble, that's good.  If his/her primary role for you is a source of extra gas and someone to help you if you screw up, that's bad.

So true!

But the gas management is easier at 100 ft. or 130 ft. and it is possible to get decent bottom times at 100 ft. without looking at staged decompression. Still if you neglect the gas management, you will likely not be a happy camper.

Your point is taken though. It drives me nuts when divers up here have a freeflow and are automatically thinking "surface". But that is because I am used to being in a position of this NOT being a great option. It is so simple to shut down the reg, let it defrost for a minute, turn it back on, and continue on with a minimal loss of air. Actually, the other divers that we teach are doing the right thing from their frame of mind if they are sharing air with their buddy and doing a safe ascent. It is just that my mentality is slightly different.

[Diverbrian]

OK then!! You're completely Crazy!

There... It's been said!

What does that say about anyone who will dive with me? Hmmm!!!!

[WreckWench]

OK then!! You're completely Crazy!

There... It's been said!

Now Heather...you are so....uh....tactful!!!

[hnladue]

Who?? Not me!!! Remember I'm the one on the boat with the rope tied to your butt!!! Hail you in and beat you!!

Besides.... I get to see first hand wacky buddy diving!!

Is that why BC's often feel like straight jackets??? Cause we're all crazy???

[hnladue]

Well!! He said:

It gives some divers a chance to call divers like me completely crazy


So I did!!!

[Genesis]

I agree in large part.

My view of when you're ready to consider things like deco, overheads, etc is when you've taken the mantra of your OW class - you know, the CESA practice - and tossed it away as not only unnecessary but dangerous.

BTW, it IS dangerous. Even in 30' of water its kinda dangerous. Its REALLY dangerous beyond about 60'. Why? AGE, that's why. Unless you have a chamber handy right where you are (as in you can get in the pot and blown back down within 3-5 mintues of surfacing), a good AGE hit will either cripple or kill you before you can get to the chamber. That's the part they don't talk about (much) when they're teaching you that CESA protocol......

Disagree, says you? Ok. Go find your instructor who certified you as an OW or even better, AOW diver (still on singles now, with no redundancy) and tell them you want to see them demonstrate a CESA from 100' after 20 minutes on the bottom. Bet 'em $20 they can't "show you." If said instructor has a lick of sense he will look at you like you're some kind of 6-headed Hydra and might mutter a few obscenities under his or her breath. No OWSI worth a nickel would take you up on that, and the reason is that they KNOW it has an unacceptable risk of getting them badly hurt - or even killed.

Now square this with the fact that this same person you trusted with your life when you took your OW class taught you a procedure for saving your own butt that they just refused to do as being too dangerous!

BTW, smart OW instructors will be using really high FO2 mixes for those first OW cert dives where they have to do a bunch of CESA 'practices' with their students. I've seen 50% bottles pretty frequently, and at some sites, I've seen 80% bottles. Why? Because more than a couple of instructors have taken severe DCS hits from that sort of bounce diving - its not safe!

The obvious question to ask is why, if such a gas choice is good for the goose (instructor) its forbidden to the gander (student), given that OW checkouts are to be performed with HARD BOTTOM DEPTHS not exceeding 60'. EANx50 is breathable to 70' safely, gives a 1.41 PO2 at 60' (so keep it to 59 to stay within recreational PO2 recommendations), and brings a HUGE safety factor improvement to those OW dives - especially if someone simulates a Polaris launch due to panic or just plain "not having it together."

Now you'd THINK that the agencies would rather teach a safer way. You'd think wrong, of course. Why? Because that would require them to deal with the fact that a lot of dives are done every day that really shouldn't be done on a single with no redundant gas supply (and no, a "Spare Air" doesn't count either), and to fix that would require dealing with the reality that diving isn't quite like bowling in terms of its risk factors and what you ought to be thinking about before you dunk your head underwater.

Therefore, rather than have to deal with teaching proper gas selection and management, proper redundancy (which in the context of deeper recreational dives means either a decent-sized pony tank or even light doubles!), and the trouble and costs of that, getting rid of the "voodoo" view towards the user of elevated FO2s, not to mention developing the proper mindset (which takes quite a bit of TIME and is incongruent with the 5-day classes ALL the agencies push nowdays) they just ignore all this and teach you to make a CESA. They do this knowing full well that if you actually DO make one from any significant depth its quite probable that you will be badly hurt or even killed due to taking their advice.

In other words, they teach you to do the wrong thing, starting before you even don your gear!

That's fine if you dive 30' deep reefs - you'll probably get away with it. It is most certianly NOT fine on a 100-130' dive. While bent is certainly better than dead, paralyzed to the point that you can't pee isn't MUCH better than dead, and that's an very likely outcome.

The only real saving grace is that equipment nowdays is pretty darn reliable, and is unlikely to fail catastrophically underwater. The bad news is that every year I read about a bunch of people who get badly hurt at quarries and such where there is cold water deep, they get down there, a reg freezes up, they get a freeflow and follow the "one true agency advice" - up they come - where if they were properly equipped they'd just shut down the offending post and switch to the other (or their pony), or even just reach back and feather the valve so they can breathe while the reg thaws out.

(BTW, you'd be surprised at how many recreational instructors don't insist that all their students be able to reach their valves. That's another of my pet peeves. Every year at least one person dies doing a backroll off a boat with their air turned off because they are unable to perform the simple act of reaching back and turning it on.)

Edited by Genesis, 27 January 2005 - 03:37 PM.

[Sophia]

Rebreathers may be considered mainstream or recreational diving one day. Who knows?

Boy, did I really start something! This is fun to watch.

It had never occured to me that some might think that my little Dolphin might make me a Tech Diver.

[maninthesea]

Disagree, says you? Ok. Go find your instructor who certified you as an OW or even better, AOW diver (still on singles now, with no redundancy) and tell them you want to see them demonstrate a CESA from 100' after 20 minutes on the bottom. Bet 'em $20 they can't "show you." If said instructor has a lick of sense he will look at you like you're some kind of 6-headed Hydra and might mutter a few obscenities under his or her breath. No OWSI worth a nickel would take you up on that, and the reason is that they KNOW it has an unacceptable risk of getting them badly hurt - or even killed.

Now square this with the fact that this same person you trusted with your life when you took your OW class taught you a procedure for saving your own butt that they just refused to do as being too dangerous!

You seem to be loosing perspective.
I can think of no safer alternitive than a CESA if you are out of air at 120' with no diver close enough to provide you air? No one I know considers it anything other than a last resort prior to drowning.

Flame On
Jim

[Genesis]

Disagree, says you? Ok. Go find your instructor who certified you as an OW or even better, AOW diver (still on singles now, with no redundancy) and tell them you want to see them demonstrate a CESA from 100' after 20 minutes on the bottom. Bet 'em $20 they can't "show you." If said instructor has a lick of sense he will look at you like you're some kind of 6-headed Hydra and might mutter a few obscenities under his or her breath. No OWSI worth a nickel would take you up on that, and the reason is that they KNOW it has an unacceptable risk of getting them badly hurt - or even killed.

Now square this with the fact that this same person you trusted with your life when you took your OW class taught you a procedure for saving your own butt that they just refused to do as being too dangerous!

You seem to be loosing perspective.
I can think of no safer alternitive than a CESA if you are out of air at 120' with no diver close enough to provide you air? No one I know considers it anything other than a last resort prior to drowning.

Flame On
Jim

I can think of several safer options, all of which are initiated on the boat before you get in the water.

A pony bottle - or doubles - come immediately to mind.

Of course that would require that agencies and instructors abandon this idea that diving is about as safe as bowling.

[peterbj7]

We have a saying in private flying - "a good pilot can always get out of trouble, but a really good one never gets into it in the first place". Applies just the same to diving and a host of other activities. Jim and Genesis are both right, but looking from different perspectives. Sure, you should never run out of gas if you plan your dives properly. Note "should", not "will". But the unforeseen can sometimes happen.

There can't be any of us with a bit of experience who haven't at some time gone deeper than we should have done on a single tank, and that either without a buddy at all or with one who couldn't (for any of a variety of reasons) help in an emergency. Suppose you haven't run out of gas or had a simple freeze-up, but your first stage has just self-destructed. Something that means you suddenly have no access to anything that may be inside your only tank. What are you going to do, other than try to swim for it? Yes, Genesis is right that you should plan for the unexpected, but the problem is that the unexpected can be, well, unexpected.

It's interesting that (according to IANTD, whom I have no reason to doubt) the biggest killer in scuba accidents is not equipment failure or running out of gas - it's panic. Many a body has been found with the means for the diver to have surfaced. Sure, (s)he might have had DCS, and possibly even an AGE (though barring some physical predisposition that can usually be avoided by technique), but he would have had a chance of living and making a recovery.

The second major factor, particularly among "technical" divers , is simply "giving up". Very surprising, but apparently true.

This is where learning "technical" diving is valuable, if it's taught properly. Once you know what mistakes others have made it makes it much easier for you to avoid that mistake yourself.

Edited by peterbj7, 27 January 2005 - 06:28 PM.

[Marvel]

This is where learning "technical" diving is valuable, if it's taught properly. Once you know what mistakes others have made it makes it much easier for you to avoid that mistake yourself.

Therein lies the key, I think. To dismiss all future training because of one poor experience is to deny oneself the opportunity of gaining knowledge & practical application that could someday save one's life. I can't help thinking of the arrogance that John Ormsby exhibited before his fatal dive on the Andrea Doria....

[bigblueplanet]

Genesis,

Wow, that is some strong opinion. AGE is only a risk if the diver does not properly exhale on the ascent. From deep depth if the person panics they can sustain a lung expansion injury from too rapid an acsent if they do not exhale and maintain an open airway. But, to say your lungs will explode and you will die is just inflamatory and unnecessarily scares the crap out of people. With that said, I am interested in where you get your evidence for these profound and certain statements. With such strong statements, I would like to read the source of your data on these experiences you have read and discuss.

I am certainly not saying that a CESA is a viable option from 100 and no one, training agency or otherwise, is either. The recommendation is 40 feet of water or less. It can be accomplished safely when conducted properly. It is most certainly not the best option. The best option is to simply monitor your gas supply and surface prior to running low. Simple and easy.

As for this being an option on a regulator failure. I seem to remember that almost all divers have at least an octopus. Freeflow or otherwise, the diver can simply switch to the octo and conduct an ascent. If we are going to teach people to dive in buddy teams then they should function as a team. Certainly going to a buddy, if that is part of the plan, is a better option than a free ascent to the surface.

There is no agency that I am aware of that does not allow you to place recreational divers with a pony bottle or doubles. Of course, with high capacity singles and simple gas management a diver should be able to conduct a dive to 100 feet with little risk of an out of air or gas event. The problem is solved before entering the water, planning the dive and monitoring gas supply.

No piece of equipment is going to save someone from a problem. I think the best lesson from tech diving is that divers should plan and dive with a mindset to prevent problems before they happen. You do not equip people out of problems. There are things that make life easier for the diver on deep dives, but to imply that you are unsafe if you use a single cyclinder on a dive to 100 feet or beyond is just silly. There are hundreds of thousands of dives done in that gear at those depths every year without incident. I can certainly talk about things I have personally seen when people use gear they are not experienced in nor have training to use where it caused more problems than it solved.

Your arguement is unreasonable.

As for the high FO2 issue, most of the cut off in the recreational arena is about dealing with FO2 above 40%. This is an equipment issue not a use issue. It requires dedicated regulators and cleaning procedures. No one is going to argue that for an instructor it might be an advantage to use nitrox mixtures during ascent training. I say might because it has not been studied. But, if the instructor conducts the drill with ascent rates that are slow and divides the ascents among several dives, the risk is very low. Instructors are not getting bent left, right and center doing ascent training, even on air. Again, I would love to see your data that forms these conclusions you state as facts.

There is an evolution gaining acceptance to use oxygen during safety stops. Gas choice is as much a part of dive planning as anything else. I do not know any instructor or agency that says you should not use nitrox. But, how much safer it actually makes you when the other costs are accounted for remains unsubstantiated. There are divers getting bent of EAN.

I see very little actual fact in your post. I would love to know the resources you are drawing your conclusions from.

Now, on to tech diving.

Walter, tech diving is a useful term and has existed for a long time. It is an accepted term now and dismissing it does not address the question. It is arbitrary. That is for sure. In the early days of technical diving, the definition was argued about fiercely. A definition has settled in. It is generally accepted to be any dive beyond 130 feet and or any dive with required stop decopression and or any dive in an overhead enviroment with a linear penetration beyond 130 feet from the surface and or outside of the light zone.

With this being said, it is a mindset thing. For as much as anyone wants to argue, it is different. Most recreational divers will kit up, jump in and there just is not much thought other than watching the computer and gas supply. As we may or may not teach a different mindset with small additions most recreational dives are this way.

Tech divers look at three phases of a dive. Predive, the dive and post dive. All three are equally important. The mindset is that all things are known and all items are considered before the dive is conducted. The dive generally has an agenda on the bottom. They are doing the dive to accomplish something. The effectiveness of the dive is based not just on conducting the dive operations but effectiveness on the bottom or during the working phase of the dive. The dive is not over till hours after upon return.

The equipment is usually different. The idea is that one is none and two is one. So, redundancy and backups are essential. Yet, we eliminate anything that is not necessary. The diving is mission oriented. It is very much fun, but it is not let's jump in and see what happens. The mindset is what distinguishes tech diving from recreational diving.

Most of this was stated before. Generally, problems need to be solved underwater not because it is a nice thing to do, but because you are dead if you don't. Recreational diving, as much as some would like to argue, you are able to make a slow ascent to the surface at any point with minimal risk of added injury if the problem cannot be dealt with. I have no idea who is training people to believe that a free ascent to the surface from 100 feet is a solution. If it is, it is the end of the solution chain when it is death or make the surface. But, realistically, there are so many things that need to happen before someone would choose that.

I find it interesting that so many new technical divers want to put their techniques on all divers thinking it is the solution to all problems. Part of the reason people recreationally dive, including myself, is to not have to worry about it. Is there added risk if I dive to 100 feet on only my single cylinder with an octo, yes probably. But, I am able to assess the risk of that decision. So, what I would suggest that all divers should be taught how to assess their risk on any dive.

Doom and gloom, inflamatory discriptions of how there is this great secret conspiracy in diving to kill people is just wrong and not based in fact. It is irresponsible because it unfairly scares people for no reason. The bottom line is that diving is safer than it has ever been. In fact, we are seeing more problems with those who believe they have a lot of experience putting themselves in harms way before they should be. They lack the training and experience to do what they think they are capable of. Whatever the reason, the little knowledge is dangerous crowd is alive and well.

I will say that reasons for tech diving are as varied as the divers who do the dives. In fact, if you put 10 tech divers in a room you are likely to hear 20 reasons. For me, it is because I can. That simple. It allows me to access sites and conduct dives on targets and areas that I would not be able to otherwise.

I view it as freedom. I have the freedom to go almost any where and dive anything. If I am willing to do the work to go there.

It is also being able to accomplish things that make a difference that few if any others can. It is a very different experience when you do a dive and something to do on that dive lives on forever after the dive. Whether it be find an artifact, collecting data, mapping a cave or discoverying a new wreck. The dive itself really is just the method of transport to go do something. It is not about the number on a depth gauge, a distance of linear penetration, or the length of decompression. In the end, all of that is just the cost of doing what we do on the bottom.

I am not an advocate of recruiting people to technical diving. I believe that it is not for everyone. But, those who have the proper mindset and develop the proper skill base find it very rewarding. It is not about the dive operations at all. 20 minutes of deco or 2 hours, is not all that important. It is about what is done on the bottom. Length of deco and other risks do play a part in determining if the dive is worth doing, but once the decision is made all of that is just necessary evils.

Those that are chasing numbers on a depth gauge are better off to pick a different sport. There are lot of tech divers out there that believe conducting the dive is the goal. That surviving the process is the accomplishment. They need to get back in a pool and repeat their training with someone that will help them be more than a gear manager. I prefer not to have to go recover them when they screw up. It is not the dive, it is what is done and how well it is done that matters. I have very little respect for those that brag about 400 foot dives are belittle those that have never been deeper than x feet. It sends the wrong message and only illustrates their own lack of experience. I am far more impressed by a great dive done in 90 feet of water than a crappy dive at 500.

I hope that brings some clarification to the topic. My long two cents.

Grant

[peterbj7]

Depressingly efficient, this SD machine. I was trying to forget it. Though actually not so efficient - Marvel wrote her post 1 hour 39 minutes too late, her time.....

Which raises an interesting question. Where are you, Marvel? Europe?

Edited by peterbj7, 27 January 2005 - 07:22 PM.

[ScubaDadMiami]

For the Tech Divers out there, what caused you to get into Tech Diving?  . . . What the heck is so cool that 40 minute stops are worthwhile?  Was it a dive site beyond recreational limits that made you get into it?  . . . Or did you just want to be educated about diving?

Rather than spend time defining when one crosses the line over into technical diving, I think we all get what you are talking about. Let's move on to the whys.

I enjoy learning as much as I can about diving related issues, some much more than others. Interests range from meteorology and oceanography to equipment design and repair. Learning "technical diving" stuff can be pretty intense but also pretty fun and interesting. I am not really a person that wants to hear things like: "Do this and don't do that. That's all you need to know." This is especially true where my life may be in jeopardy due to lack of this knowledge. So, I enjoy finding out about diving related subjects in the kind of detail that the experts know.

Second, I enjoy the challenge of planning a great dive and then pulling it off as planned. It's kind of like shooting for the perfect "10" in gymnastics. This can be even more rewarding when carrying out "technical diving" due to its inherent increased complexity.

Long decompression stops may not sound like much fun. However, it is a real challenge control one's ascent rate while also hitting each stop exactly on time. Then, there's the added challenge of keeping within a foot or two of the required depth for each stop for extended periods. All of this can be further complicated by gas management and equipment issues like wearing a dry suit (and venting it properly while ascending), carrying double 120 tanks along with two decompression tanks, and doing things like shooting lift bags, monitoring gauges and checking the written decompression profile while in aggressively shifting currents. It is pretty awsome to leave the water with a job well done.

Perhaps you are reading this and saying to yourself, this sounds like too much effort. Some people will think like this and some will think it would be a real rush to make it all come together. Some won't know until they get to see the world that this kind of diving opens to them.

When we dive on these deeper wrecks, for example, they are often real ship wrecks and not artificial reefs that have been prepared for divers to enjoy. It's like diving into history! Also, there are often many more types and numbers of fish life in these ranges since there are not divers frequently around to scare them away.

Heck, I even enjoy taking out my equipment and getting it ready the night before the dive. It's a fun challenge to plan and mix gas as close as possible to the planned mix (which can take some doing--especially with trimix).

You either get into this stuff or you don't. That's what it's all about for me.

About the only part that is not fun for me is carrying and washing the equipment. Somehow, I have just never been able to get into that stuff. I welcome anyone who wants to carry my stuff and wash my gear for me to join right in anytime.