Diver one of sixteen to die using high-tech gear

[Groovekitty]

This post is relative to the entirety of the current thread - I'm confused...I thought the purpose of this forum was to exchange information. This post started out as informative and interesting and now has turned into a testosterone laced personal vendetta by Buddy Inspiration supporters.

Any information CCR divers have to offer is always welcome and of interest. Why they feel they are being attacked is of even more interest. If you feel that your method of diving, be it CCR or OC is best for you - great! Questioning the safety and reliability of the CCR or OC is not a personal attack to anyone - it's important to question all methods of diving. If we don't question how else will we come up with new and better SCUBA equipment and diving procedures?

The responses I've read on this thread also puzzle me. Why do you feel personally attacked if someone is pointing out factual information about CCR's? Is it because you don't like to hear that you spent thousands of dollars on sub-par equipment that is flat out dangerous - even when used properly? Is that you have something to prove? Or is it because you're on the Public Relations payroll for the Buddy Inspiration and looking to spin things in your favor to promote sales?

I think that ALL opinions are important and need to be shared on this forum reguardless of dive experience. To ask for ones dive experience without first offering and posting your own is a little cowardly, wouldn't you agree?

Also, CCR information, like anything else, can be obtained without having actually used one. Personally, I like to read up on something and gather as much usefull information about it, be it positive or negative, before I die trying something for the first time wheather it is Trimix, OC, DPV, Cave Diving, etc..

It's not a competition, diving is for fun, remember?????

[jasondbaker]

Okay, here are the ground rules. We are going 12 rounds, bout is ended by knockout or decision, let's keep it above the belt....

I don't have the sense that people's personal honesty or integrity are being questioned here. Let's not let this discussion go there. Keep it focused on the gear and the associated dive techniques. You have an audience of divers here that are open minded and want to hear both the pros and cons of the various issues.

I know people that buy motorcycles. They probably are exposed to more risk than the average driver. I don't fault them for that decision. I just hope they have the training and experience to handle the bike. I like the fact that they have the freedom to choose.

At the same time I think people should be able to buy CCRs. Trying to compare the safety record or techniques with standard OC seems to be somewhat of an apples/oranges comparison. Yes you are underwater and could be breathing similar gases, but the gear and techniques are different. I sense that people buying CCRs go into it with the understanding that there is a different set of requirements than standard scuba diving.

Maybe diving doubles with the standard "H2" configuration is safer. But risk is something that is always balanced with rewards -- otherwise none of us would leave dry land.

What many of us uneducated, non-CCR owners want to know is: a) are there increased risks diving a CCR versus typical rec scuba, b) what techniques do you use to manage this risk?, and c) are these risks openly discussed in the CCR community and with the manufacturers?

I love technology. I live in this world every day. I can see this type of technology becoming more the norm in the future. Is it 99.999% ready today? I don't think so. But if you can't live with that, don't do it.

[DanL]

Ahhh, the MNScuba baby matures and enters the "terrible two's"...

Still a GREAT board, and still more friendly, balanced, informative and fun than many others out there (take a look at some of the digital photography boards - yow!)

Winter blahs have set in - let's be looking fwd to diving vs talking about diving...

Cheers,
Dan

[DRE]

Bob,

I'm glad to hear you took cave training from Lamar - he's a great guy and definitely knows what he's doing in terms of diving education.
My diving approach is completely based upon what Florida cave explorers have been developing for years. One of the aspects which I believe has made possible the kinda dives that certain groups in Florida have done and are doing on a regular basis (from WKPP to small two diver exploration teams - backmount and sidemount) has been their dedication to continuing education and reevaluation through accident analysis. I assume you own a copy of Sheck's Blueprint for Survival, which spearheaded all of this.
Don't worry about your flame retardant panties, I have absolutely nothing against you nor any CCR diver in particualr, my problem with what's been going on with CCR's in the last couple of years is that that same kind of accident analysis has not been a major part of the CCR community. It seems to me that the general attittude is too much to simply blame it onto user error without coming up with new ways (through perfecting the gear, diving procedures, team awareness, etc) to possibly avoid the reoccurence of such incidents.
I know that the way I conduct my dives I have every possible angle covered in terms of gas planning, lights, deco, etc. that in case the shit hits the fan my team will be able to respond swiftly and accurately to the situation. From what I've seen from certain CCR divers this attittude seems to be lacking.
If you feel differently I'd love to go over some scenarios with you and would like to get your input on how you guys handle things.

As far as my knowledge of the unit is concerned, I have checked into certain aspects of the Buddy, which made me not want to dive it because I felt I'd be putting myself at far too great a risk for something happening beyond my control (and that's the last thing I want when I'm UW). To give an example concerning the O2 sensors: the issues with the sensors are that in the humid environment found in the breathing loop of a Buddy Inspiration, condensation forms on the sensors, which can affect their ability to give accurate results. I believe, but correct me if I'm wrong that the cells on a CIS Lunar are surrounded by a hydrophobic membrane to prevent this problem. Also, O2 sensors can fail if they are exposed to certain elements, such as salt (sea water) and also can fail if they are subjected to mechanical stress (being bashed around on a boat).
The sensors need to be calibrated, you can do this on the surface, however, you can't do this at depth. Whenever you calibrate any piece of equipment, you should calibrate it at the two extremes of the range you are measuring over. With the Inspiration, you can only calibrate on the surface, therefore the maximum PO2 you will be able to measure will be 1, however the Inspiration runs at a high setpoint of 1.3pp02, but you can never calibrate the unit at that setpoint. You may think that if it shows a pp02 of 1 in pure 02 on the surface, then that's fine, but I would rather be able to make sure the sensors were going to accurately measure across the range of pp02 that I am going to breath, and more importantly, at higher levels, such as 1.6 and above to let me know that there is a problem.
So the issue, as far as I am concerned, is that how confident are you that the readings you are getting on your handset are accurate. If they are inaccurate, then the unit will mix the gas incorrectly and you will be none the wiser, until its too late. Remember an electronic CCR is constantly mixing the gas underwater (the idea of which I find very scary).

[DRE]

Read my article on Holistic Hogarthian and you'll know where I'm coming from - and no, I don't need any dives on a CCR to make an informed opinion about it: I usually invoke rule #1 for that kinda stuff and call the dive at the dock.

[igotoofar]

Hey, Stop picking on my motorcycles :

[rcojr]

I can"t speak to the Cislunar I never considered it as it was way out of my means(about $25,000)
Checking the sensors(there are three) at depth is easy. Being a good Tec. diver you always know what fraction of 02 you are breathing and you know how deep you are. It's a simple matter to take f02xata and calculate the PP02. When you know that you just do a Diluent flush and check to see if your 02 sensors are reading correctly. John J. that just posted to the list puts duct tape on the back of his handset and enters all the numbers on the surface(no math a depth)

[beeger]

DRE beat me to some of the comments on I wanted to make. But seeing that my flight out of town tonight was delayed, I'm going to go ahead and type something up anyway.

The fact that the Inspiration prompts you with a list of items to go through is not really the point. I could do the same thing with my slate/notepad by just writing out the list. Your example of example of, “When prompted by the machine to check your O2 valve if you choose to press the OK button without turning on the O2 tank is that the fault of the diver?” is well stated. I agree with what I think to be your implication - it is the fault of the diver. However, and this is a big however, the types of situations you describe are a moot point on OC. My O2 bottle is turned off until I need to use it. I can visually and physically verify this with absolute certainty before and during the dive. I can jump in the water with my right post turned off and I’ll know damn quick that it is turned off (in which case I will reach around and turn it on). Same principle applies to the left post: if I don’t figure it out during a S/Valve drill then the fact that my SPG is not moving would be a clear sign. Same principle goes for the manifold.

But I’m not only talking about the speed at which a problem is brought to my attention, but also the manner in which this is done - it will be obvious that there is an issue. Because it is obvious and made readily apparent I can then address and resolve the issue immediately. If it is some sort of “catastrophic” event a team member will be there to assist me as needed. An electronic machine that is mixing my breathing gas cannot and does not alert me in any meaningful way when something is amiss.

I’m not willing to be my life on a piece of electronic equipment that can, and eventually will, fail. The whole idea of a computer determining on the fly what I’m breathing and adjusting as it sees fit does not sit well with me. My understanding is that the O2 sensors on the Inspiration are located in the breathing loop. The diver’s breath makes this a humid area. The colder water surrounding the breathing loop is going to cause condensation inside the loop. Condensation on any O2 sensor is a bad, bad thing (look how many O2 analyzers are sold in water proof, protective cases). Exposing these things to water, not to mention the general beatings taken by dive gear will throw off the readings. I get uncomfortable with the idea of something mixing my gas for me on the fly, especially when we are talking about a fragile, electronic device that can be prone to failure. What’s worse is that when it does fail the inherent design can not actively alert you - you won’t know. Instead you simply spike or drop your ppO2 and suffer the deadly consequences.

So the issue, as far as I am concerned, is that how confident are you that the readings you are getting on your handset are accurate. If these are inaccurate then the unit will mix the gas incorrectly and you will be none the wiser, until it’s too late.

[DRE]

I can\"t speak to the Cislunar I never considered it as it was way out of my means(about $25,000)
Checking the sensors(there are three) at depth is easy. Being a good Tec. diver you always know what fraction of 02 you are breathing and you know how deep you are. It's a simple matter to take f02xata and calculate the PP02. When you know that you just do a Diluent flush and check to see if your 02 sensors are reading correctly. John J. that just posted to the list puts duct tape on the back of his handset and enters all the numbers on the surface(no math a depth)

I'm sorry if I'm misunderstanding this, but if you have a machime that gives you your bottom gas by mixing O2 and a diluent on the fly, your fraction of O2 is determined by this mixing process. So aren't you basing your fO2 on the a priori assumption that that is what the machine is going to give you anyway. So in case the O2 sensors are all off the mark, the machine will mix you a gas which the machine assumes gives you the correct ppO2 at depth and that's the readout you'll get on your display (based upon the data from those same O2 sensors). Now you have to assume that's something might be wrong, do the diluent flush and then find out that your sensors are off the mark, all while you're 260ft inside the Kamloops. Then you have to deploy your bailout bottle (unless you have left the bottles outside of the wreck to maintain a smaller profile) because you can no longer be sure of what your machine is mixing for you - that is, if you haven't toxed out yet at that point and make it to the surface and do your entire deco on your bailout bottles. At the same time your team member has a catastrophic gas failure on his Inspiration, his deco bottle starts freeflowing and then what?
Granted, this might be somewhat of an unusual scenario, but weirder things have happened...

Also, could you please elaborate on how you calculate your gas requirements for any given dive?

[jasondbaker]

What is a diluent flush?

I assume the 3 O2 sensors are providing triple redundancy. If one of the sensors fails do you abort the dive? How do you know if the O2 sensor has failed? I'm wondering if the sensor will fail to provide data or if the sensor's data will differ dramatically from the other sensors.

When the O2 sensor(s) fail and the unit starts mixing the wrong gases, won't the computer readout tell the diver what ppO2 is being mixed? Even if it gives the wrong number shouldn't the diver know if the number is correct or not? I have to believe that the CCR diver isn't on autopilot. He should know these numbers at each given depth.

Is there a case where the correct pp02 number is on the computer display but the unit is incorrectly mixing the gas?