Posted by John Walker on February 19, 2001 at 11:15:15:
In Reply to: slow ascent rate posted by JRM on February 19, 2001 at 09:40:29:
I don't know if I want to get to involved in this topic because of such an huge history in decompression theory, through dissolved gas theory to bubble mechanics.
But, I would like to share woth you that diver have some degree of bubble formation on most dives, even recreational dives. The size and number of bubbles appears to be responsible in decompression illness.
One way to create large bubbles or even a lot of bubbles is to increase the gradient between tissue gas pressure and inspired gas pressure/ambient gas pressure.
You can maintain these bubble to a degree by not increasing that gradient too much. You do this by slowing down that ascent rate and on staged decompression dives this requires deep decompression stops.
We know that if we start overly offgassing our fast compartments we create bubbles at depth which can not be rectified in shallower depths.
Our shallow stops (20'-10') are where we focus on slower tissue compartments. These are the fatier compartments that gases like Nitrogen and Carbon Dioxide are not only highly soluble in but are reatined and are slower to offgas.