Posted by Wayne on March 10, 2001 at 11:34:05:
In Reply to: Lungs Changing Size... posted by mattschechter on March 10, 2001 at 10:55:22:
It is an air volume/pressure problem that kills you. The air in the lungs will expand as the pressure is reduced. If it is not vented through breathing, the pressure will build up to the point where lung damage will occur. Some folks seem to think the lungs are like empty bags into which air is moved in and out. In actuality they are more like a dense sponge with the many small pockets providing a massive surface area through which gasses can be passed to and from the blood.
The Navy had training tanks used to teach submariners how to escape a sunken sub. In the early days, lung overexpansion injury had not been contemplated and two men held their breath from 18 fsw and were killed. Now they teach NEVER HOLD YOUR BREATH!
Some people think that it takes a large ascent distance to kill. It does not. Always breathe, maybe really really slow and pausey, but ALWAYS BREATHE.
Wayne