Going Deeper than 130'

[TSandM]

I'm going to quote someone who doesn't post here any more: Mike Ferrara would frequently say, "Yes, you can DO this dive the way you're talking about, but for me, it makes much more sense to plan and execute it as a proper staged decompression dive." I think Mike is a very wise man. Rather than try to cut corners, or do a bounce . . . get the proper equipment and the training, and go down and ENJOY being there, for enough time that it makes sense to do the dive at all.

 

[explorer08]

Buckaltc,

HG Frogman is absolutely right - 160 feet in a cold lake with low visibility is a technical dive requiring training, progressive acquisition of experience, proper planning, the right equipment and a solid buddy/team you are familiar with. Approach this exercise with rigor and you will be rewarded with a new skill set and hopefully some great new dive companions.

Splitting hairs around what is and isn't technical these days is irrelevant to your post. So please don't be distracted by that discussion and seek out a good instructor/training organization.

I agree with nearly everything you said - except the word "technical" in your first sentence . And I don't think that discussing the definition of "technical" is splitting hairs und irrelevant for the TO.
The discussion about the definition of "technical" shows, that there are several (at least two) completly different approaches to the topic of deep diving. And the TO is now on a level were it becomes time for him to have a look over the fences of agencies, because in the terrain he is now beginning to enter, many things are not simply black or white. One important example is all the decompression stuff he will have to deal with. But this is a topic of it's own and he will learn in short future.

 

[explorer08]

@Devon Diver
I agree with most things you said, but the devil is in the details.

Let me give an example.
When you are talking about recreational diving equipment, it sounds to me that you are talking about single tanks with single outlets, one first stage with two second stages - the typical "recreational" configuration.
Now take me. I am living and working as a fulltime instructor in Turkey and I'm diving in the aegean sea. Most of my dives are training dives with my students or dives where I am guiding groups of certified divers. So all these dives take part in the area above 130ft/40m. Usually I am conducting these dives on single 10l or single 12l tanks (sorry, I am not familiar with the american tank sizes). But now the difference comes. All my tanks are equipped with double outlets and I always use two independent first stages, with second stage and SPG. Also I always dive with two computers (except on very shallow dives, above 10m). So even on these dives I am diving with redundant equipment. And, by the way, this configuration is very common amongst recreational divers in Germany, Austria and Switzerland, who are frequently diving in cold water.
Now on leisure dives I like to do it a bit deeper.
For me that means the range between 40-60m. But this is my personal decision and I am aware that other people may define their personal "comfort zone" different.
But because I don't want to reconfigure my complete equipment all the time, I stay on my standard configuration, just with some slight changements. If I go deeper than 40m, a 12l single tank is minimum. Depending on were I plan to go I switch to a single 15l tank and I may add a 4l stage tank with air or a 10l or 12l stage tank with nitrox40 (in my area anything above nitrox40 is not available). And even if I use nitrox40 for decompression, I use my computers in air mode.
I would call neither me nor my equipment "technical", but I call my way to conduct my dives a sound way.
If you call it "technical", than it's your definition.

What is for sure for me, is that I am diving at the borderline between "Rec" and "Tec", but because it's a weak borderline different people may define it different. And that is what I want to make aware for the TO.

 

[hg frogman]

Rather than try to cut corners, or do a bounce . . . get the proper equipment and the training, and go down and ENJOY being there, for enough time that it makes sense to do the dive at all.

Sound advice, but (just out of curiosity) :

What do you (TSandM) call a bounce, say, at 150 feet ?

And what isn't a bounce (i.e. which bottom time at 150 feet, assuming a square profile, isn't a bounce) ?

Thanks.

 

[DevonDiver]

@Devon Diver
I agree with most things you said, but the devil is in the details.

It is indeed.

Personally, I like to draw a distinct line, based on personal experience and IMHO best practice to eliminate the grey line.

It is a difference between moderated and unmoderated risk. The steps taken to moderate risk are incremental...and vary with experience, training, equipment and diving conditions.

All my tanks are equipped with double outlets and I always use two independent first stages, with second stage and SPG.

This is certainly preferable to a single cylinder/single regulator.... but it still isn't a redundant air source. There are a lot of issues that can still arise from that configuration that could cause you problems on a deco dive. It eliminates risk from a single reg failure, nothing else. That said, it is still a step taken to moderate risk.

For me that means the range between 40-60m. But this is my personal decision and I am aware that other people may define their personal "comfort zone" different.

Exactly, which is why personal considerations play an important role. However, if your approach was 'standardised' it would leave less experienced divers in great jeapordy than if they drew a distinct line between rec and tech IMHO.

What is for sure for me, is that I am diving at the borderline between "Rec" and "Tec", but because it's a weak borderline different people may define it different. And that is what I want to make aware for the TO.

I agree in principle, but not in practice. It is quite easy to draw a firm line between rec and tech. Such a line would enable better clarification on training and equipment needs for developing divers.

As you said... you don't want the hassle of changing configurations between dives. I wouldn't let a bit of hassle (replacing a single tank wing with a double tank wing) deter me from the best practice approach of moderating all the risks, not just some of them.

What do you call a bounce, say, at 150 feet ?
And what isn't a bounce ?

I would look at two aspects.... the dive objective...and the bottom time.

If the dive objective was to 'reach depth and return', then it is a bounce.

Also compare that objective with bottom time... the bottom time has to be meaningful. I've done short duration dives, just to photograph black coral... and then headed up....say bottom time around 10 minutes. That was short, but meaningful. I've also done short, deep dives to get a shot line onto a wreck etc. To drop down deep..and spend a few seconds looking at a non-descript sea floor is not meaningful.

 

[boulderjohn]

This thread has devolved into an argument over the definitions of different terms, especially the term "technical." Although there are a couple of "official" definitions for some of these terms, none of those definitions is universally recognized. Consequently, many of the posts in this thread can be summarized as "my definition is better than your definition."

At some point, I think you have to say, "So what?"

I have a clear definition that differentiates between recreational and technical diving, and I am positive a number of people on this thread would agree with me whole heartedly.

But some would not agree, with equal vigor.

Perhaps this might be an interesting discussion in its own thread, but I don't see the point in it.

Some people might be interested in reading this Wikipedia article, which has an interesting approach to the topic.

 

[explorer08]

Personally, I like to draw a distinct line, based on personal experience and IMHO best practice to eliminate the grey line.

But because things are not always just black or white in life, that always means to abstain from things which would be absolutely possible. Or it would mean to make efforts which are absolutely unnecessary. It’s a bit comparable to calculating your dives just as square profiles while the concept of multilevel diving still exist. IMHO distinct lines most often are just a matter of liability and I understand that this is much more a point of concern in the States than in Europe.

It is a difference between moderated and unmoderated risk. The steps taken to moderate risk are incremental...and vary with experience, training, equipment and diving conditions.

The problem is that the definition of what a moderated risk is and what an unmoderated one, is a very personal decision as well.
For example, I consider my way of diving a moderated risk. And if we are not willing to accept some risk, we should not dive, because for example the whole decompression stuff is a moderated risk. Everything is based on assumptions and mathematic models. The only proof are test dives and the basic concept is “What works, works”. And my way of diving did work for more than 25 years without any incident.

This is certainly preferable to a single cylinder/single regulator.... but it still isn't a redundant air source. There are a lot of issues that can still arise from that configuration that could cause you problems on a deco dive. It eliminates risk from a single reg failure, nothing else. That said, it is still a step taken to moderate risk.

As you could read before, the deeper I go and the more decompression time I expect, I add additional tanks as well. The only difference is I don’t do it in the way of a twin-tank configuration. And that is because my way is more flexible and more convenient for me.

It is quite easy to draw a firm line between rec and tech. Such a line would enable better clarification on training and equipment needs for developing divers.

Now we come to the point.
Of course it is easy to draw a firm line. It makes things easier for the agencies but it restricts the divers. Therefore I accept firm lines, but as recommendations only (outside of formal training).

If nobody ever would cross the firm lines in life, we never would have any progress!

But I understand boulderjohn as well.
What I wanted to point out to the TO - that he is entering an area where things are not so clear as he might have expected and that it's worth to look an listen around a lot - should be clear for a while.
Meanwhile we are very much in the details and if the TO doesn't want us to continue this discussion here, we should stop at that point or someone should open a new thread for it.

 

[Kevrumbo]

I have some questions about going deeper than 130'. I really have no desire to get into advanced tech diving for it's own sake, but I do want to get to around 160' or so. I live in Michigan and there are some things in Lake Huron that I want to see one day. I am a PADI Divemaster and I work mostly with Scout groups. I did this because I felt it was a great way to dive a lot and keep the costs down but I'm not a Divemaster for a living. I'd like to learn some more and do more wreck diving and to that end I'd like some advice on which way to go. I want to keep costs down of course, but I won't cut corners on safety. I'm a little turned off on DIR right now but I could be convinced--not a slam on DIR just what I read--I don't know enough to have a real opinion.

What is the minimum/recomended level of training and equipment needed to get to 160'? And where would you go for training? I know the question is a little lame, I'm not a minimum prep guy. The goal of my post right now is only to get enough information so I can start asking better questions.

Simply put (again). . .

To the OP: do you have enough gas to do this dive? Can you produce a gas & deco plan that covers the mission as well as emergency contingencies within the given environment? If not, start your technical training progression & matriculation. . .

Period. Point blank. End of thread.

(Some sample info on the choices of classes you have out there:
IANTD, DSAT, GUE Course Details @ Tech Asia)

 

[openmindOW]

A diver should not be doing technical diving "for its own sake" nor should he be diving to 160 feet for its own sake. A dive to 160 feet is a decompression dive and, by definition, a technical dive. .

Thank you.

Dive within the appropriate limits.

 

[hg frogman]

Sound advice, but (just out of curiosity) :

What do you (TSandM) call a bounce, say, at 150 feet ?

And what isn't a bounce (i.e. which bottom time at 150 feet, assuming a square profile, isn't a bounce) ?

Thanks.

Here are common bottom times for the first dive of a day for single-tank (15 liters at 232 bar/120 cubic feet) CMAS *** divers on French Mediterranean Sea wrecks (no penetration; good visibility; two dives maximum per day, with more than 4 hours of surface interval; deco generally done on backgas):

30 minutes at 30 meters/100 feet
20 minutes at 45 meters/150 feet
15 minutes at 51 meters/170 feet.

These are not long bottom times compared to what some technical divers do, yet I woudn't call them "touch and go" dives. But for sure this is a very relative notion and maybe a good reason for diving with a truly tech setup like TSandM said. My wife and I rarely spend less than 20 minutes on such a wreck at 45 meters/150 feet (that usually involves a bit of multilevel profile) and we generally feel that was long enough, but this is very subjective.

I am telling this just for information's sake, I am not saying this is the best way, or even a good way, to dive.

These bottom times are generally set as rules (= maximum bottom time allowed) by the dive operation during the briefing, with some other rules relative to gas management.

By the way, "bounce" has at least two meanings: one is quite similar to "touch and go" (that is much less ambiguous) and one is used by commercial diving companies (e.g. COMEX) to differentiate "saturation dives" that can last for days at working depth, from "bounce dives" with usually less than one hour of bottom time.