Why plan decompression with a Gf (lo)?

[KenGordon]

I have an additional question that I'll open in a new post so I don't go too OT, but first could I check I have this (in pic) a/ is the ranking correct, b/ what do we know about the slopes (are there intersections etc I should add). I realise some are black boxes / proprietary. I'm asking this q so I don't propogate bad info.

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Take a look here http://www.ddplan.com/reference/mvalues.pdf look at table 2.

An issue with what you are trying to do is that there are many compartments and different ones limit the diver depending on the profile. So for comparing where the overall limit line lies across algorithms you need to know which compartment is the limiting compartment and that depends on the profile. Depending on the m values and half times chosen one algorithm might be more limiting than another for one profile but less limiting for another. This is especially true with the GF modification to ZHL16 where the actual limits depend on the first stop depth, minimum ceiling or phase of the moon depending on the programmer.

 

[EFX]

Well... obviously the pprN2 in the lungs.... ie... the ambient pressure. There can be nothing else on the other side of that equation to my way of thinking.

The key thing is the tissue gradient. A tissue/compartment can continue to on-gas during ascent and it can start off gassing with a slight supersaturation. Context is everything here. Eric, you know the model better than most so I'm sure you are aware that some compartments are off gassing while others are still on-gassing. It's exactly THAT map that we're trying to navigate during an ascent. R..

I knew the answer prior to asking the question. I wanted rossh to clarify his statement since Storker so succinctly laid down the basic premise which you state as so obvious.