Posted by MHK on November 02, 2000 at 09:47:26:
In Reply to: Which page? posted by Eins on November 01, 2000 at 22:59:43:
EINS,
I'm confused.. I think you misunderstand the connection between EAD's and the RGBM -v- Buhlman models. If I misunderstand something let me know but as I see your question we have a few concepts that are perhaps getting confused.. Let me see if I can speak to the issues:
EAD a.k.a. Equivalent Air Depths - is basically a method of calculating a depth. If this sounds strange it's due to the following.. If you are at 90' and are diving regular air ( ie; 21% 02 ) this concept is inapplicable because you are simply at 90'. However, one of the benefits of diving Nitrox is that you get the benefit of diving a gas with an elevated level of 02. This elevation of 02 means conversley that you have reduced levels of Nitrogen ( N2). N2 is narcotic and this causes Nitrogen Narcosis at depth. So by increasing the 02 at 90' you head thinks you are at 75' ( using a 36% ). That's one concept..
The second concept is the current algorithm used in connection with computing the M- value of a given tissue compartment. An M-value is the Maximum value of inert gas pressure that a tissue compartment can tolerate without presenting symptoms of DCS. The Buhlman method for decompression calculations is expressed in linear relationship between ambient pressure and tolerated inert GAS pressure. This is why we refer to Buhlman as a dissolved GAS model..
Weinke, on the other hand is proposing the RGBM Reduced Gradient BUBBLE Model which emphasises on gradients and focuses on a bubble model. The coefficents of both the dissolved gas model and the bubble model can act interchangably but are different models..
Given the above I maybe a little unclear of your point because to me the AED bears little, if any, relationship to the 2 seperate decompression models ( ie; the Buhlman GAS model and the Weinke BUBBLE model). Hopefully this clears it up a bit...
Later