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camerone · 25th April 2008, 20:41

Quote: (Originally Posted by andrespp)

The question is as follows: bearing in mind that for a time I shall be using the unit on multilevel dives, not deeper than 30 meters, with no deco, do you think that carrying bailout is necessary?

My thinking (I maybe wrong, that´s why I am posting this question), is that having the unit the BOV, the bailout is not necessary on this kind of diving, specially if care is taken and avoid being deeper than 18 meters when the air SPG is below 100 bares.

Good practice is to _never_ count on a BOV for anything other than a couple of sanity breaths, unless you're plumbing it into significnat offboard gas... and even then, you have scenarios that it's not so good for (caustic cocktail being one).

Do the math on a question like this, even as back-of-the-envelope.

Take your 3L cylinder, and subtract some reasonable amount for diluent usage on a typical CCR-friendly dive. Subtract some slight amount more for wing inflation, and then suit inflation, too; my guess is you'll be down to what is now (effectively) a 2 L cylinder as "bailout," assuming you're starting your dive completely full -- as would be the first dive of the day case, and not later ones.

A 2 L will barely get you to the surface from 30m, certainly no saftey stop, and that's with a reasonable SAC. Add stress from a bailout, and you'll quickly see that going it without on a dive plan like that is not a wise choice.

25th April 2008, 20:41	#10 (permalink)
camerone New Member Current Rebreather/s: Evolution Dolphin Other Rebreather/s: Dolphin Join Date: Oct 2005 Location: Seattle, WA Posts: 66	Re: Should I carry bailout?? Quote: (Originally Posted by andrespp) The question is as follows: bearing in mind that for a time I shall be using the unit on multilevel dives, not deeper than 30 meters, with no deco, do you think that carrying bailout is necessary? My thinking (I maybe wrong, that´s why I am posting this question), is that having the unit the BOV, the bailout is not necessary on this kind of diving, specially if care is taken and avoid being deeper than 18 meters when the air SPG is below 100 bares. Good practice is to _never_ count on a BOV for anything other than a couple of sanity breaths, unless you're plumbing it into significnat offboard gas... and even then, you have scenarios that it's not so good for (caustic cocktail being one). Do the math on a question like this, even as back-of-the-envelope. Take your 3L cylinder, and subtract some reasonable amount for diluent usage on a typical CCR-friendly dive. Subtract some slight amount more for wing inflation, and then suit inflation, too; my guess is you'll be down to what is now (effectively) a 2 L cylinder as "bailout," assuming you're starting your dive completely full -- as would be the first dive of the day case, and not later ones. A 2 L will barely get you to the surface from 30m, certainly no saftey stop, and that's with a reasonable SAC. Add stress from a bailout, and you'll quickly see that going it without on a dive plan like that is not a wise choice.
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