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AD_ward9 · 10th June 2008, 12:00

Quote: (Originally Posted by Brad_Horn)

Mike,

I note that study was done on N202 (Air/Nitrox Dil), it is interesting how it ties in with regard to a ~30m depth limit, with Gavin Anthony's presentation at DAN in Jan 08 even though NEDU was looking at WOB and Qiniteq End-tidal Co2. DAN Divers Alert Network {Approx Min 26:00}

Would be interesting to compare those NEDU results with the diluent in the Mk16 Mod1 being Heliox (10/90, 16/86, 20/80 etc) instead of N202.

Thanks for the link

regards
Brad

It varies considerably depending on the rebreather. The worst case multiplier we have measured was 2.8, and the best case 7 times. It depends very much on the flow type that predominates. For a well designed rebreather like the Mark 16, I would expect a number around 6.5, so the depth limit for heliox is 6.5 times that for nitrox, for the same breathing resistance and WOB limits.

Just on the independent testing of rebreathers, we are publishing the results in a couple of weeks (including Meg, Boris, Dolphin, Inspo and DL single and double rebreather units). We are trying to arrange things to include the rEvo that Paul Raymaekers has very kindly offered to bring over, but it is coinciding with a move of our facility from a building to a new container with power,water and drainage that we are having fitted out just as a lab after Fire and Factory Inspector concerns over the amount of O2, pressure vessels etc we have in a building - it has been a battle for about 2 years. We would like to do an update later in the year to this report, and include the rEvo, RB80, PRISM and Mark 16. Anyone able to offer a loan of a PRISM or RB80 in Europe, please let me know. We will cover shipping costs.

Alex

10th June 2008, 12:00	#604 (permalink)
AD_ward9 - Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jun 2005 Location: Scotland Posts: 2,004	Re: Comprehensive list of all accidents Quote: (Originally Posted by Brad_Horn) Mike, I note that study was done on N202 (Air/Nitrox Dil), it is interesting how it ties in with regard to a ~30m depth limit, with Gavin Anthony's presentation at DAN in Jan 08 even though NEDU was looking at WOB and Qiniteq End-tidal Co2. DAN Divers Alert Network {Approx Min 26:00} Would be interesting to compare those NEDU results with the diluent in the Mk16 Mod1 being Heliox (10/90, 16/86, 20/80 etc) instead of N202. Thanks for the link regards Brad It varies considerably depending on the rebreather. The worst case multiplier we have measured was 2.8, and the best case 7 times. It depends very much on the flow type that predominates. For a well designed rebreather like the Mark 16, I would expect a number around 6.5, so the depth limit for heliox is 6.5 times that for nitrox, for the same breathing resistance and WOB limits. Just on the independent testing of rebreathers, we are publishing the results in a couple of weeks (including Meg, Boris, Dolphin, Inspo and DL single and double rebreather units). We are trying to arrange things to include the rEvo that Paul Raymaekers has very kindly offered to bring over, but it is coinciding with a move of our facility from a building to a new container with power,water and drainage that we are having fitted out just as a lab after Fire and Factory Inspector concerns over the amount of O2, pressure vessels etc we have in a building - it has been a battle for about 2 years. We would like to do an update later in the year to this report, and include the rEvo, RB80, PRISM and Mark 16. Anyone able to offer a loan of a PRISM or RB80 in Europe, please let me know. We will cover shipping costs. Alex Last edited by AD_ward9 : 10th June 2008 at 12:26.
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