Ø Descompresión en el buceo con mezclas (V03-01) (Spanish)
Ø La Decompressione “Ratio Deco” nelle immersione subacquee con miscele ternarie (V03-01) (Italian)
Ø Standard Gas Blends & Ratio Deco (Hebrew)
Exchange, Partial Pressure Gradients, and the Oxygen Window, by Johnny E.
Brian, Jr., M.D.
My understanding. The paper explains the decompression advantages of breathing pure oxygen under pressure (1.6ATA), moving further from the simple idea of increasing the inert outgas gas partial gradient without decreasing the absolute pressure. The so called “inherent unsaturation” in the body’s blood is due to the different degree of solubility of O2 and CO2. This phenomenon is more significant under pressure (this is the oxygen window concept) and it is good for the diver for shrinking existing bubbles of inert gases. The paper, not only explains why breathing O2 is better than breathing air at depths from 0m to 6m, but also explains why breathing O2 at 6m of depth is better than doing so at less depth. This means that, when using O2, all “Haldanian” stops above or equal to 6m should be made at 6m to get an additional safely factor in the decompression process (or to reduce the decompression time if the diving computer accounted for this phenomenon). This does not mean that an O2 stop at 3m is wrong; it is in fact good under the classical dissolved gas perspective (Haldane), and it is better that doing the stop with air. It means that an O2 stop at 6m is even better than at 3m under both dissolved and free gas perspectives (RGBM).
Understanding M-values, by Erik C.
My understanding. The paper explains the concept of M-Values in WORKMAN and BÜHLMANN models, and it is very useful for understanding why the introduction of safety factors on the outgas Haldanian maximum gradients of tissues (very low percentage gradients at high depths and slightly low percentage gradients at shallow depths) gives rise to decompression profiles with deep stops (deeper than classical dissolved gas stops) which are coherent with the free gas decompression theories. It aids in understanding in which manner the introduction of safety factors in the decompression software (such as Deco Planner and others) affect the overall decompression profiles.