Deep Air VS CCR

[helodriver87]

I can't handle that cruise control analogy. So convoluted and ridiculous. And the argument he ultimately ends up making is that sometimes you have to override cruise control, so we fixed that by removing it. Along with the seat belt, mirrors, doors, and traction control.

 

[broncobowsher]

That sounds like a good train wreck to watch this evening.

 

[flymolo]

That sounds like a good train wreck to watch this evening.

Well then I suppose you are welcome

 

[Jack Hammer]

Also, where did he get 20 litres from? Perhaps he

Yeah. Perhaps he misquoted the 20 litres/min flow rate, but still, the rest of his analogy still seems way off..

20L a minute would be a common, though on the high side, consumption rate for a recreational OC diver. For a CCR diver around 1L per min would be metabolized, possibly 2L if swimming very hard.

I understand mis-speaking happens, he doesnt say it once or even correct it later. His video has way too many things that are dont add up or make sense. With as off as it is I'd think he'd take it down and redo it if he just mis-spoke (about 40 times). ??

 

[rjack321]

Wow! His analogies are awful, overexagerated, and dont even come close to how CMF and MCCR works. Most all his numbers are way off too. 20L a minute? 10 mins swimming and no noticeable drop in PO2? 1.2 drops to 1.98? WTF??

Like I said thank god they have no market share

Per Leon, many of the Meg parentage UTD CCRs have since been converted back to eCCRs. Not sure how many they sold of either variety though

 

[broncobowsher]

Well then I suppose you are welcome

That was one hell of a train wreck.

I think I just met the first rebreather diver I don't want to dive with.

 

[flymolo]

20L a minute would be a common, though on the high side, consumption rate for a recreational OC diver. For a CCR diver around 1L per min would be metabolized, possibly 2L if swimming very hard.

I understand mis-speaking happens, he doesnt say it once or even correct it later. His video has way too many things that are dont add up or make sense. With as off as it is I'd think he'd take it down and redo it if he just mis-spoke (about 40 times). ??

Yeah I don't know what he's referring to there being 20 litres per minute. But that definitely doesn't describe the flow rate of a cmf or leaky valve, considering those should be around 1 litre per minute.

 

[broncobowsher]

Zero understanding of minimum metabolic rate. Your need for oxygen never comes to a stop, unlike your car.

 

[stuartv]

I wanted to find out more about the UTD ccr choices and watched a few videos they put together some time ago. However, after watching this video:

I'm just not sure he is correctly describing the experience of diving an mccr with cmf or needle valve installed. Am I missing something here?

O. M. G! What a moron!

Is there a more retarded closed circuit setup anywhere??

"Your body is going to metabolize a minimum of 0.7l of O2 per minute. But, it would be unsafe to have a CMF injecting 0.7l of O2 per minute into your loop."

"Instead of injecting O2 into the loop to replace the O2 your body metabolizes, we're going to inject dil into the loop. When you consume 0.7l of O2, we'll replace it with 0.7l of TX21/35."

Yay! I always wanted to figure out a way to use less O2 and more of my dil... *cough* *cough*

 

[stuartv]

I wanted to get an estimate on dives that are done below 130 feet. What percentage of those in your observation are done on CCR and what percentage on Deep Air - no helium? Since no official numbers may exist, peoples individual observations would be a huge help. Thanks.

Since I got on CCR, all my dives past 130 have been on CCR. And all my dives on CCR are done with helium. I only get my dil cylinders filled with TX. That is part of the beauty of CCR. I don't have to wait until I know what dive I'm planning to do next to get my cylinders filled. When I come back from a trip, I get them all topped up - dil with TX21/35 - so they're ready to go on a moment's notice, for whatever dive opportunity comes along. If it ends up being a short dive to 20' in the local lake, I don't care. The amount of helium used for that is so small that the cost is inconsequential (to me).

On OC, I have done dives on air to a bit over 180. But, probably only 4 - 6, in total, past 150 (on air).

Among the small # of guys I have dived OC with, past 130, we have generally used air for anything to a max of 150, and helium for anything deeper than 150. I would still not bother with helium, on OC, for anything down to 150 - unless it was expected to be a particularly challenging dive (which, anymore, I would not do on OC at all).