Two more rebreather patches

Rodrigo Severo rodrigo at
Mon Oct 27 10:56:30 PDT 2014

On Mon, Oct 27, 2014 at 3:33 PM, Paul Sargent <paul.lionseye at> wrote:
> Certainly for the moment I'd keep it simple. Personally I'd favour no
> numbers, rather than wrong ones, so I'd forget about computing constant rate
> O2 usage. It's just not that useful IMHO. It's too far removed from the
> amount of O2 I use on a dive, and gas planning the CCR part of a dive really
> isn't that big a deal compared to OC.
> For example: A one hour dive should be 20bar (60 litres) out of a standard 3
> litre cylinder - just calculating 1 litre a minute. That's just way off. I
> always use about ~50 bar on a ~40 metre dive, so I tend to make sure I've
> got at least 100 bar when I jump in.
> (or have a missed a different method of calculating things in the various
> mails?)

The method of calculation is just that but, as I see things, it would
happen the other way around:

After this dive Subsurface would show you that your oxygen SAC is 2,5
l/min (50 bar of a 3 l cylinder used on an hour dive). So on your next
planning you should use 2,5 l/min for oxygen and not the usual 1


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