neon half time tables

[lns92]

Hi Dr. deco. what are half times. Thanks, LNS

 

[divebutt]

Hmm.... sounds interesting, especially given the price of helium. What would the price of neon be compared to helium?

 

[Dr Deco]

Hello Ins92:

Tissue Halftimes

Tissue halftimes differ from halftimes in football in that there is less to watch. Actually, there is noting to see with tissues. It is a mathematical concept from JS Haldane that allows the calculation of decompression tables.

The term comes from radioisotope half-life and indicates the length of time for one-half of the original isotope to decay to some new isotope. The length of time is termed the halftime. In terms of tissues, and diving, the term indicates the differing lengths of time necessary for dissolved nitrogen [or helium] to be washed out through the capillaries of the tissue. The term also applies to uptake of inert gas.

Haldane knew that blood did not flow equally to all tissues of the body. Some tissues, such as heart and brain, required a high flow of blood. Other tissues such as fat did not need so rich a blood supply since they were mainly for storage (e.g., of fat). He therefore made a series of halftimes that were 5, 10, 20, 40, and 75 minutes. These were sufficient for the diving of his day.

Saturation diving has required the addition of more and longer halftimes. Somefo these run up to several hundred minutes.

Dr Deco :doctor:

 

[Dean810]

Hmm.... sounds interesting, especially given the price of helium. What would the price of neon be compared to helium?

My understanding is that Neon, if you can get it, is MU MU MUCH more expensive than Helium. If you want to try it, you should get a sponser. :11:

 

[Gene_Hobbs]

Neon

Neon has been investigated as a diving gas but only for deep diving (500 fsw) by military or commercial divers. The reports were by Bill Hamilton PhD and came out of his laboratory in 1974 at Ocean Systems when I was just a novice barophysiologist employed there. These reports were prepared for the US Navy who sponsored them, and I do not know where they can be obtained anymore.

http://www.rubicon-foundation.org:8080/dspace/handle/123456789/3778
Sorry, I have the others but have not had time to add them.

References

Vorosmarti J, Bradley ME, Anthonisen NR. The effects of increased gas density on pulmonary mechanics. Undersea Biomed Res. 1975 Mar;2(1):1-10.

http://www.rubicon-foundation.org:8080/dspace/handle/123456789/2693

D'Aoust BG, Stayton L, Smith LS. Separation of basic parameters of decompression using fingerling salmon. Undersea Biomed Res. 1980 Sep;7(3):199-209.

http://www.rubicon-foundation.org:8080/dspace/handle/123456789/2869


UHMS abstract:
http://www.rubicon-foundation.org:8080/dspace/handle/123456789/23

Other papers:
http://www.rubicon-foundation.org:8080/dspace/handle/123456789/2922
http://www.rubicon-foundation.org:8080/dspace/handle/123456789/2863