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lbihler · 28th September 2006, 12:21

Hi all,

I m going on a Deep Virgin Wreck diving livaboard south thailand next week. I just can t figure out which gases I would take for bailout. I m quite a beginner on deep wreck dives and wanted your opinion before doing a fatal mistake.
Profile is usually 60 metres for 40 minutes, 2 dives a day. Onboard I use 100% (98) and 14/44 trimix, 1.0 ppO2 bottom 1.4 ppO2 ascent for that mix.

Knowing that they have O2 at will at 6 metres under the boat and that I can not really count on other divers as I will probably be the only CCR diver and as everybody tends to go solo.
Last time I took 12litres Air and 12 litres 36% as bailout, which is enough for me to complete all my deco on OC. Thing is I ran out of O2 during the dive (stupid me, don t ask) with a fully functionning unit and had to ascent in semi closed, which took me ages to deco.

Question is, what would you guys use, knowing that available gases are any mix below 40% O2 including air and trimix, and 100% O2 ?

I was thinking about taking a 12litres Air at 200 bars
and a 12litres 02 at about 100 bars (no booster on the boat) so that even if I work a bit at the bottom I have enough O2 to finish in fully closed and I can
fly the unit manually and spare my back gas for emergencies.
I ll be a bit short on OC ascent if the problem occurs at the end of the dive and I do not find the deco bars (not a probable case, brilliant viz and no current). But again, in semi closed mode, I can even loose the down line and finish my deco without problem.

What are you guys thinking about it ? Any risk I forgot to consider ?

28th September 2006, 12:21	#1 (permalink)
lbihler New Member Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Jan 2006 Location: Bangkok Posts: 56	Bailout Gases for long 60 metre dives Hi all, I m going on a Deep Virgin Wreck diving livaboard south thailand next week. I just can t figure out which gases I would take for bailout. I m quite a beginner on deep wreck dives and wanted your opinion before doing a fatal mistake. Profile is usually 60 metres for 40 minutes, 2 dives a day. Onboard I use 100% (98) and 14/44 trimix, 1.0 ppO2 bottom 1.4 ppO2 ascent for that mix. Knowing that they have O2 at will at 6 metres under the boat and that I can not really count on other divers as I will probably be the only CCR diver and as everybody tends to go solo. Last time I took 12litres Air and 12 litres 36% as bailout, which is enough for me to complete all my deco on OC. Thing is I ran out of O2 during the dive (stupid me, don t ask) with a fully functionning unit and had to ascent in semi closed, which took me ages to deco. Question is, what would you guys use, knowing that available gases are any mix below 40% O2 including air and trimix, and 100% O2 ? I was thinking about taking a 12litres Air at 200 bars and a 12litres 02 at about 100 bars (no booster on the boat) so that even if I work a bit at the bottom I have enough O2 to finish in fully closed and I can fly the unit manually and spare my back gas for emergencies. I ll be a bit short on OC ascent if the problem occurs at the end of the dive and I do not find the deco bars (not a probable case, brilliant viz and no current). But again, in semi closed mode, I can even loose the down line and finish my deco without problem. What are you guys thinking about it ? Any risk I forgot to consider ?
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