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No Dennis Ihave no connection with the odessey. I have purchased one. 
I don't beleive either Rich or I are arguing with you persey it is just that
you insinuate all other units are not good and that a semi closed is
worthless. While for the diving I do I enjoy the benefits of fully closed I
also feel there is areas where semi has applications. I also think the
design concept of the Odessey is the most applicable for safe diving. As far
as safety goes my opnion is it is the most safe of any rebreather on the
market. 

From a deco standpoint &  bottom time it will not touch fully closed. I plan
to have a variety of units eventually to address specific needs with.

Dennis I think the ccr500 is excellent and I hope to be diving one I also
think these other units are quite good as well.
Tom Mount

At 02:24 AM 7/9/96 +0000, you wrote:
>
>> geeze Tom (obie one) i expected more from you than this.. are you
>> connected in any way with the odessey?  of course there have been changes
>> in the electronics and other technology along the way.. hell this is the
>> 90's.  I sorta got the same comments, or questions from rich privately, 
>> (good one's really, but come on you guys, do you think we are really all
>> that stupid).
>
>Sometimes I wonder ;-)
>
>Seriously, though, my only point was this:  You can have new technology,
>or 3.5 million hours of testing, but not both.  The value of the testing
>is in finding failure points.  There is a diminishing returns at some
>point where you no longer find new failure points, and only get a more and
>more accurate idea of failure *rates*.  Now, when you have this
>information (failure points and rates of failure), then the smart thing to
>do is correct the failure points which have the highest frequency
>(balanced against some measure of cost of failure) by re-designing the
>relavent components. Once you've re-designed them, though, the "testing
>hours" clock gets reset to zero for those components in the system.  So,
>either the CCR500 is exactly the same as the CCR1000 (3.5 million hours of
>testing, but old technology), or the most frequent failure points have
>been re-designed (new technology, but considerably less than 3.5 million
>hours of testing). Again, you can't have it both ways. 
>
>I guess my only suggestion is, instead of saying things like "every 
>component has had more than 3.5 million hours of testing" (as I think was 
>an assertion made at the start of this thread), you should say something 
>like "is the latest in the BioMarine line of rebreathers, which 
>collectively have on the order of 3.5 million hours of testing".  That 
>way you can make the point that a lot of people have spent a lot of time 
>on the *predecessors* of the CCR500, and to a greater or lesser extent 
>the discoveries made during all that testing have gone into improving the 
>CCR500 design.  Presumably, then, the *wisdom* obtained from all that 
>testing has been transferred to the new design, with the incorporation of 
>the latest technology.
>
>I'm looking forward to seeing these things up close & personal.  There 
>should be two Cis-Lunar Mk5's in Hawaii in August - maybe we can schedule 
>a session in the UH pool for some side-by-side comparisons?
>
>> I can't believe you even brought this up... either one
>> of you...  and one more point, for everyone out there.. this ccr stuff is
>> not magic, it't not even that complicated, so let's stop trying to make
>> everyone that doesn't have a unit think that we are smarter or better than
>> they are.. anyone out there could (and will) dive one easily.
>
>What's your point, and who are you addressing it to?
>
>> i don't want to hurt anyone's feelings, but i do not, and will not ever,
>> understand why anyone would build a semiclosed unit..  if anyone buys
>> one of these units they will be trying to trade it or sell it so they can
>> get a fully closed unit..  it's happening already...
>
>I imagine that people would opt for a SCR (at least a passive-addition
>system like the Odessey) because they don't want to put in the amount of
>training required to become disciplined enough to consistently stay alive
>on a fully-closed unit.  I agree in basic principle with you on the SCR -
>except for being quieter, I'm not sure I see the advantages over a set of
>double nitrox cylinders.  However, don't underestimate the amount of
>dedication it takes to consistently stay alive on a fully closed unit. 
>The fundamental reason why they require more discipline is that you can
>more easily die before you realize anything is wrong. Furthermore, you're
>more likely to go hypoxic on a SCR in shallow water, whereas you are more
>likely to go hypoxic on a CCR in *deep* water. Also, you only go hyperoxic
>on an SCR if you exceed the depth limits.  You can go hyperoxic on a CCR
>at any depth greater than about 20 feet.  No, it's not a magic carpet, and
>it's not rocket science.  But it sure as hell isn't scuba diving either. 
>
>Rich
>

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