March 3, 2006 Class Notes

Dive Tables by Shannon McAteer

The most important reason for having dive tables is to prevent decompression sickness.

    DCS is a series of symptoms related to ascending to quickly or not staying with in the limits of the dive table. Some of the symptoms are bubbles forming causing joint pain and damage.

    The bubbles are not always easily seen. There are micro bubbles or silent bubbles. These tiny bubbles wear down your joints over time and are not always diagnosed. They can also form into larger bubbles.

    To treat someone suspected of having DCS, you should bring them to the surface have them lay down and relax, then make them breathe 100% oxygen while taking them to a decompression chamber. The importance of 100% oxygen is to raise the partial pressure of oxygen in the body forcing the partial pressure of nitrogen down. This is also called off gassing.

    Ways to prevent DCS is to ascend slowly from every dive, stay with in the limits of the dive table, and do your safety stops.

    There are different ways of doing safety stops. A person can stay at 15-20 feet for 3-5 minutes. There is also another way called deep stop (Rule of Halves). A person starts their safety stop deeper. You stop half way up the water collumn for around a minute then do your normal stop at 15-20ft for 2-3 minutes. This always you to off gas earlier and it is better prevention of micro bubbles. It also helps to slow you ascent naturally.