how do pressure groups relate to saturation levels

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Nephrops

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I have been playing around writing scripts to implement the Haldane and Buhmann algorithms. This is not too hard as there are plenty examples around. However, one aspect that I cannot put my finger on is how the saturation levels of the respective compartments translate into "pressure groups" or "repetetive groups" such as prominently used by the RDP.

I expect it's something to do with hofar you have progressed within the range of surface N-levels and M0 for the most saturated compartment, but sofar I have failed to find a match.

Could someone point me towards an explanation of this?

Thanks,

NephropsN.
 
You have a fine hobby. Please let us know how else we can encourage you.

Regarding this specific question, maybe you can start your research with the first report from the NEDU: Repetitive Diving Decompression Tables (1957).

Appendices A & B show their "UNIVAC methods" and experimental data from dives, but the whole thing is a rollicking good read for someone who is interested in decompression theory.

Please keep us updated as your code grows.

Best regards.
 
Thank you. The joy is going the way, not reaching the destination :)

The EDU document didn't help me. Though it mentions the repetitive groups, for an explanation it sees to refer to itself. A good read is the patent of the wheel. It gives much more background than just a tech description. About the presure groups it says:

These alphabetical indicia correspond to certain arbitrarily defined tissue pressure ranges, namely:
A=Range from 33.5-37 FSWA
B=Range from 37-40 FSWA
C=Range from 40-42 FSWA
D=Range from 42-43 FSWA
. . . increasing by l FSWA/letter of the alphabet until
Z=Range from 64-65 FSWA

However, these pressure ranges are quite high (given the 0 min at surface would be 26.1). I therefore don't find a good correspondence with the RDP table. The writer (Raymond Rogers) cites two algorithms he has used, but sofar I haven't been able to track these: copyright numbers TXu 278 551 and TXu 291 717.
 
https://www.shearwater.com/products/teric/

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