Recreationall TRIMIX

[puddlejumper1]

Do you have a six point harness in your car? Why not driving is a tricky business and the force exerted on your body in a crash at 30mph (assuming a 170# person) is somewhere around 5,100#. My somewhat obscure point is that there is an acceptable point of risk. Now if auto manufactures put 6 point harnesses in thier vehicles less people would use them which would increase the risk.

Apply this to diving. The more complex something becomes the less likely that someone will perform it correctly. Now remember I think a recreational trimix class is not a bad idea. Is the level of risk of now having to determine PO2 and the correct mix and all the other factors worth it. Just to have a more clear head. I think not. As for Narcosis there is a lot of argument over the application by people smarter than I. Just how narcosis affects people is still not understood. Also the Martini law is not a straight line application but more of a bell curve by many theories.

I have not done as many dives as some of you. But I regularly dive all over the great lakes and a lot in Florida. I am sorry but I do not see the use of Nitrox that is proclaimed here. In fact in over 200+ dives now I have not hardly seen any Nitrox use at all. Most of the use does appear to be grouped around the metros.

I am sorry to hear about you not knowing about a LDS in Appleton (there is actually two). Knowing ones diving enviornment would seem like a wise idea to me. Knowing where you can get a good fill would seem even wiser.

My mix station is coming along nicely and should be operational by April maybe May. This all depends on when the compressor comes back. And how much ching I gotta spend on the boat.

[FreediveWI]

I believe that George likes to site a Navy study where they matched up a group of divers to play chess. Half the group would be on the outside of the chamber and the other half would be insdie the chamber pressureized to 40'. They would rotate the divers around to account for all ability levels. The divers outside of the chamber beat the divers under 40' of pressure every time.

I do a lot of C02 tolerence training for freediving, as does Fred (FreediveND), but I wouldn't trick myslef into believing that it helps me in any way with narcosis- just in working under high C02 loads.

I still see recretional trimix as a better stepping stone to a deco class rather than having someone do all the skills while impared and then letting them experience a clear head. That was the smae sillyness I had to go through before I took trimix. It was called Extended range and doing abunch of silly skills at 220', on air, didn't really teach me much about trimix. It was just another hoop ot jump through to prove that I could do something that I had been doing for some time. If someone want's to go to mix they should simply be allowed to go to it with out any extra hoops.

I have watched more than one deco student swim off in a daze at 130-150 in Wazze to know that they are impared down there. I wasn't teaching the class, but photographing them for friends of mine who were. Since I was on mix I could tell very easily who was straight and who wans't. As a result of this one of my friends no longer even teaches Extended range and sends everyone right to mix for safety sake.

If someone is already using nitrox it isn't that big a step to analyze and plan for triox. As long as your bouyancy control is ok, which it should be for anyone venturing past 60', then your good to go.

I remember hearing that there was a place called Inland seas in Neenah. I am not sure if they are stil there or not. About 10 years ago Iknow there was a shop in FOn Du Lac that I would pass on the way up to Red Granite. Last I checked they were now a motel. I have always been able to find a shop where ever i wnet, or was able to bring along enough tanks, or a blending station, to not have to worry aobut it.

One of the best things about freediving is not having to worry about fills, or even charter boats since we drag our dive kayaks along with.

BTW: I bought a cheap palm for $75 for Circut City and added the D-plan program for around $50. You can put this into a water proof case that they sell at your local kayak shop and use it while on the boat without havingto worry about ruining it. The money that you save, compared to using your laptop, will help to offset the cost of a HE analyzer. THe only argument that i ever heard against a He analyzer was for those people who just dive heli-air, and not true trimix. Once you start adding 02 and helium to your mix it gives me great peice of mind to know exactly wehat I am breathing- especially as mixes can change over time if you don't use them shortly after blending. You may think this is overkill, but Iknow of others who think diving anything but air on 250' dives is overkill- I wouldn't do that either.

Jon

[puddlejumper1]

A lot of good points that I agree with. I agree that Deep Air Decompression / Advanced Nitrox is a waste and even dangerous to teach. I agree that having a class for recreational mix is not a bad idea. i do not like palms of any type (Ihave less than that into my laptop) and will stick with V-Planner. I have been daeling with gases longer than they have been used for mainstream diving and can tell you from experience that most of what the dive industry teaches is B.llSh.t. If even half of the mantra was true there would have been mass deaths in the welding industry going back over 50 years. ( I just love when someone tells me that a tank can only be sent to Hydro testing once for + rating since my O2 tanks have been + rated since the 40's when they were manufactured.) The common misconception that a mix may change overtime is a trivial falsehood. Show me one tank and I will bow to the gods. But after literally thousands of tanks having the right mix for years (diving is not the only industry to use mixes and is one of the newest) I can tell you that it just can not happen. That said if a tank is seriously mixed wrong than you could conceivably get a layering of gasses (not unlike a layered drink) but really since all the gases have different weights it would not stay that way. But I have never seen this happen yet and do not think it is likely. I have seen more where the initial read was off someone compensated and then had to dump because the mix came up strong. I have tanks that are sitting around the shop for over a year. We use this in some of our diagnostic equipment and have nevr had a problem with the mixes.

[Chris H]

I don't know of anyone who thinks the mix may change over time, and it has never, until now been presented that way. However, I would feel better if I and the divers on my team knew that what the mix sticker says is actually what is in the tank.

I was going to stay out of this, but there are a few other things.

I agree that you don't necessarily need to know ANY skills to understand a Nitrox or trimix table. However, you will be hard pressed to find somebody willing to dive with you if you are a cluster in the water.

I am very pleased with what I learned in Deco Procedures and Advanced Nitrox. I am glad Gert took the time to push us and make things go wrong during the dives so we had a chance to show we could handle the dive when things weren't going exactly as planned. Although Gert ultimately made the pass/fail decision you can bet your butt that I am a more confident diver after the class. Knowing that I can reach my own valves and that I know where my equipment and my buddy's equipment is makes me feel better anytime I'm doing a dive. That "filler" may very well save me or my buddy some day.

Take what you want from the whole DIR thing, but a lot of it makes tons of sense. There are plenty of places to get into that whole thing, we don't need it here too. You can read about something all day long, and spout off all sorts of other facts and figures to show somebody how much you know; but in the end what happens under water is what counts. It is pretty hard to switch to your deco gas if you can’t find it.

I am looking forward to the DIR-F course not because I want to tell somebody why they are doing it wrong, but so I can get pushed again. This training will never make me a worse diver.

Read all you want, but I read a book about how to drive an F1 car and I don't pretend to be an expert on that :

[puddlejumper1]

This is not the first time I have heard or read this either.

Now I refuse to get into anything about the DIR match going on. I have some people that I think of highly (Jeeze Chris I even consider you one ;D) that seem to beleive in DIR. I have no concern about taking a class from a DIR instructor. There have been many ways to do it right. And a large % of divers in technical diving do not dive DIR now. The "whole" concept is one I do not believe in period. I do not hold others who believe in it in contempt.

I spent the entire last summer looking at how I was going to change my system. You in fact made several dives were I was not happy with how I was trimmed out and how my configuration was. Several of the people I have made dives with have made very solid recommendations that I have or will incorporate. I spent the pumpkin dive this year not carving pumpkins, but becoming accustomed to a deco bottle making sure I was comfortable with how it worked how I had things routed and if I could in fact hand it off in the event of an emergency. I spent my last dive this weekend getting comfortable with the change to a backplate. Guess what I found that I didn't have the ability to reach my valves (even after pulling the gear up on my back). So now I need to make adjustments and raise my tanks up in the bands. This is just good diving though. I have not seen anything that has happened in these classes that I will not have become proficient at before I take the Advanced Nitrox / Decompression Procedures class.

I will say this there is no reason in my mind (and in the mind of a lot of divers) why the voodoo hush hush mentality is out there about trimix and decompression. None of the skills taught in conjunction with these classes are necessary (they are a damned good idea for the application) for the understanding and know how to perform these dives. The most use I intend to get out of trimix is going to be below 150' using doubles and performing decompression diving. Doing the same dives on air and using a 50 mix would be no different. I didn't need to read a book to learn how to do that. I was taught the basics in Nitrox when I took that course. You certainly did not become proficient at the skills you learned in the most recent classes you took. You did learn them and decided to become proficient at them I am simply doing the same but without the instruction first.

What I relly want to hear before I make the leap into an instructor is things like "wow he really drilled us in calculating our PO2" or "Jeeze I got so good at planning out my entire dive that I could do it blindfolded" oh " And he really taught us a lot of new skills that will increase our diving awareness and ability on how to get out of the water in the event of a problem." But that is not what I have heard.

Tell me what is the difference between RGBM and VPM? Why is the Buhlmann decompression theory considered a flawed decompression model. What programs use these models? This is the kind of information that is going to help keep you alive.

Nor did I learn this in a book. While I have plenty of books for reference material. I also do not learn by aping others. I want to know the reason for what is happening. Then if and only if the reason is good and can add to my safety or diving enjoyment will I incorporate it into my way of diving.

[FreediveWI]

When mixing trimix you can get helium to leak out of a tank unless you put something else in to bind with it. This happens in other areas. I was Talking to one of the MRI tech's at GE once about the helium they used in their machines. He said it did leak out over time and they had to refill it. With nitrox mixes this isn't a problem. THat being said I still will analyze every mix I dive before I get into the water. I also log these mixes and double check all of my teammates before I get in, as they do the same for me.

Say what you will about DIR, but I dove lot's of different stroke set-ups over the years before I stumbled upon DIR. Everything about the system works as advertised, and it saves money over some of the crap that is being sold as "tech gear" out there.

I can't say that I ever learned too much from any scuba course I ever took. There is just so much info on the web that you can get for free, and I have a couple of decades of dive experience to put it to use, that the courses are pretty much hoops to jump through to do the dives I want. The course that I did learn the most from never even offered a c-card, as it was considered a clinic. THat was when I got to dive with a bunch of world record freedivers in Miami a few years ago. It was one of the most informative weeks of my life

If your looking to get hammered in your course on dive planning, and execution, I would highly suggest a class from GUE. Second to that, I would recommend Greg Such as the best , local, trimix instructor.

I did happen to learn a thing, or two, the last time Deep Blue brought in a couple of GUE guys to teach the Dir-F class. I wasn't taking the class but happened to be in there when they talked about doing a 270' mix dive and flying to Milwaukee less than 2 hours later- something that you won't see in you Buhlman table. It was also discussed that if you do yur deco, meaning deep stops, correctly that you can throw out the altitude diving rules that have been so ingrained in the dive industry over the years.

That being said, I think that we have gotten off track from the rec trimix thread that this started as.


Jon

[Deep Blue]

There is so much good stuff to reply to in this thread, I hardly know where to begin, but here goes.

Helium analyzers are great tools for divers that dive mix. I am not as concerned that a mix changes over time, but for example, when I am on a trip, I am remixing tanks by air topping and I have at least 3 or 4 different sets of tanks. With a high helium and a lower 02 mix, the 02 will not change as significantly as the helium content, so if you have different mixes, ie. 16/60 and you air top it from say 1500 to 3000, you get 18/30. Now the difference between these two mixes if you are using an 02 analyzer that is only +/- 1 percent is neglibile. The only way to positively ID the gases is with a Helium Analyzer. But the difference is pretty major.

The 16/60 has an END of 60 feet and a 30 minute dive has a 57 minute deco using 50 percent and oxygen. The 18/30 has a 130 END and 76 minutes of deco on the same dive. Hardly a minor difference.

I believe that you are much better off passing on the 1300 dollar VR3 or such nonsense and putting down 800 dollars on a helium analyzer and use the balance as a downpayment for some good trimix training.

As far as training goes, a comment was made that dive planning was the most important part of trimix training. I can teach a monkey to easily plan a very safe dive. I am NOT saying that dive planning and a theoretical knowlege are not important, but there are so many great tools out there that make dive planning easier than ever before, the critical portion of this type of training is things like valve drills and learning to deal with problems that happen when you are underwater. As you move into deco diving, you need to be able to deal with anything that may happen without needing to return to the surface. This ability can only be developed by constantly being pushed during training to use your reasoning skills and problem solve when you are not in mortal danger.

Ask any of my students, and they will say that I constantly challenge them to do more and to push their limits and to constantly evaluate the 3 P's Pressure, Position and Plan as well as the impact of any failures on the 3 P's. Failures and different levels of harrassment SHOULD be part of this level of training. It is critical that divers at this level understand their true capabilities.

I still remember the student that was giving me gas about requiring that they learn to buddy breathe a stage bottle, while doing a good deco, since he has never had a deco reg go south on him. I swear to you, that next dive, when he pressurized his deco bottle, he blew up his first stage. For real, I didn't even set him up. What I am trying to tell you is that you may never have had any of these things go wrong, and you may have 100's of dives under your belt, but that doesn' t mean that you shouldn't train and learn what to do if it does.

The critical difference is that the instructor must be able to walk that fine line between harrassment to improve a diver's skills and challenges them, and harrassment that pushes the diver beyond the their safe limits and simply destroys the diver's ego and self confidence.

The biggest problem with failures, is that they limit your options. Multiple failures force you to deal with an increasingly limited set of options. If you have never gone down this path, and lives are at stake, making good decisions can be almost impossible, now add a buddy in that may be making their own decisions, and the clusterfuck factor goes up geometrially when you can least afford it to.

Life gets dramatically more serious as you venture beyond the 200 foot range. Mistakes that may be minor at a recreational level can and many times are fatal at this level.

Ok, now with that is off of my chest, I can get back off my soap box, and I am looking forward to seeing responses. I know this was a long post, but ask anyone that knows me, once you get me going, I am like the energizer bunny, I just keep going and going and going....

[puddlejumper1]

All very good points. However before we digress any further from the original thread. might I suggest that we either split off at this point or start a new thread entirely.

[dfreeman]

This may belong on another thread, but I am trying to understand how the helium in a trimix blend changes over time? Also, what gas binds with helium? I have not heard of these things before.

Just trying to understand the theory behind this.

Doug

[Deep Blue]

Ok folks, lets start a new thread. Unless someone has more on recreational trimix. There look to be three or more possibilities.

Technical dive planning

DIR

Technical dive training techniques

Helium Analyzers pros and cons

Gas Blending Theory, although my quantum gas partical theory is a bit rusty

You guys pick or come up with your own and I will do my best to chime in.