The (bad) assumptions
A model is only as valid as the assumptions behind it. Most models are based upon certain "knowns" such as accepted no-stop time limits for the different depths. But these time limits/tables are only valid if the diver performs the dive in the same manner the tables were tested. Most tables were tested with only mild to no exercise being performed before, during or after the dive ... so their time limits would give a lower incidence of bubbling than what the diving public would probably experience. So always dive conservative since you are more than likely to have more micronuclei and thus more bubbling after a dive than the acceptable limits of the table when doing the same dive as a table test subject (who was probably sitting around with very little activity waiting his turn to get in the chamber for his test dive).
The conditioning
As much as many of us would hate to admit it, the condition of our bodies do make a difference. Age has been shown to affect the degree of bubbling from a dive. Older divers have more bubbles from a dive than younger divers. The reason is not exactly known but may be accounted for by having more adipose tissue. Adipose tissue can act as a gas storage area and could result in an overload and release of gas later.
The physical shape of a diver is also important. It has also been shown that the greater the body uses oxygen, the less risk one has for DCS. The usage of oxygen simply shows the oxygen used by the tissues which is an indication of blood flow rates. Obviously, the better the blood flow the better the off-gassing during decompression or after a dive.
Decompression Tactics
All divers need to decompress properly. This includes recreational divers doing deep safety stops and ascending slowly. The benefits of a slow depressurization can be seen by a simple experiment. Take two soda bottles side by side and open one very slowly and the other one rapidly. Notice that the one with the rapid decompression results in more bubbling.
In addition to the rate of decompression through the stops and making sure enough pressure is kept on the diver during decompression, divers can also speed up their off-gassing (as well as in-gassing if not careful at depth) by doing very super mild movements. We hesitate to call it exercise because that makes it sound like work must be performed ... which is exactly what a diver does not want to do. Performing work or exercise will generate micronuclei and make decompression worse. Instead, very slow and ultra gentle movements are desired, such as bending the arms and legs slowly. It is the change in muscle form that will open up capillaries and make blood flow occur and result in better off-gassing due to the increase in blood flow. But again, anything more that amounts to activity can generate micronuclei and make things worse ... so always error on the side of caution by doing ultra gentle movements The exercise that some divers think is helpful during decompression is a big no-no.
Another procedure a diver can perform to reduce decompression risk is to obviously spend more time decompressing. But the point of this article is to suggest and explain procedures that a diver may not have thought about. Another of these procedures is for a diver to remain on their final decompression gas for a period of time after surfacing (in addition to avoiding anything other than mild activity). This will assist with the elimination of gas whether bubbles are present or not. But assuming a proper conservative decompression was done, bubbles should not yet really be present. Bubbles take time to generate after a dive (but this may differ with mandatory decompression stop dives). The reason for this is that it takes awhile for gas leaving the tissues to randomly bump into a micronuclei. As the micronuclei grow and provide a larger surface area, the rate of gas bumping into the micronuclei increase. If bubbles are avoided upon the initial surfacing, then there will be a window of time in which the diver can increase gas elimination by breathing a decompression mix at the surface before the bubbles grow - which in turn will reduce decompression risk. But again, even if bubbles are present, this procedure will still assist in a diver eliminating gas.
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