  The Ostwald ripening phenomenon for gas bubbles in a liquid consists mainly
in gas transfer from smaller bubbles to larger bubbles. An experiment was
carried out in which the Ostwald ripening for air bubbles, in a liquid fluid
with some rheological parameters of the human blood, is reproduced. There it
has been measured time evolution of bubbles mean radius, number of bubbles and
radius size distribution, where the initial bubbles radii normalized
distribution behaves like a Tsallis ($q$-Weibull) distribution. One of the main
results shows that, while the number of bubbles decreases in time the bubbles
mean radius increases, therefore smaller bubbles disappear whereas the,
potentially dangerous for the diver, larger bubbles grow up. Consequently, it
is presumed that such a bubble broadening effect could contribute, even
minimally, to decompression illness: decompression sickness and arterial gas
embolism. This conjecture is reinforced by the preliminary results of Ostwald
broadening to RGBM (Reduced Gradient Bubble Model) decompression schedules for
a closed circuit rebreather (CCR) dive to 420fsw (128m) with 21/79 Heliox gas
mixture.
