Physics of diving question...

[arcFlash]

I read John's post as wanting to know what part of the body correlated to what tissue compartment. That made me wonder if it's useful outside of academics. So the logical question is, given the chance, can I effectively alter my decompression to limit the risk of getting bent in a really bad place? I can live with a bad elbow, knee... but getting bent in the spine and being paralyzed isn't. So, it sounds like no. The tissue group that limits the NDL is likely to be the control on the entire dive including the planned decompression component.

I would have interpreted the model to say the NDL is limited by the fastest compartment but the slow(er) control the decompressing times. That said, the spine is likely slow being it's closed off by the meninges. If I want to avoid a bent to that body part, do I have any options, theoretical as they may be?

Biology is a messy thing but it's not random.

My former manager got a spine bend on a repetitive 60 ft dive for 30min on air. lost her legs, had 5 chamber rides and still has issues walking. She had a pfo and didn't know it.

John,
This doc from 2000 talks about the original model and how half times were created and by whom.

Note: this document describes lab testing of animals resulting in death.
"Haldane
calculated these half lives to represent what happened in
the body. Moir’s data gave him his 20 minute half time.
Haldane used Hill and Greenwood’s3 data of nitrogen
excretion to provide his 5 minute half time. That is based
on the nitrogen content of urine. Hill and Greenwood
considered that as the kidneys are very well perfused in life
they represented what we now call a fast tissue. They
experimented on themselves in a chamber under pressure
where they passed urine every 5 minutes or so. The urine
was passed out of the chamber and the nitrogen content
measured. JS Haldane’s experiments on goats gave a 75
minute half life. From his mathematical calculations he
showed that, if the body had an equal perfusion, then this
would represent a 10 minute half time. I have not been able
to find the origin of his 40 minute half time."