Capt Jim Wyatt
Hanging at the 10 Foot Stop
Staff member
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Scuba Instructor
Yes indeed--I have been told that a 1.5 PSI pressure increase can lead to AGE.
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A colleague of mine was on surface-supplied air at about 25 feet, squatted down to pick up a heavy object on the bottom, held her breath when she stood up with the object, maybe 2 1/2 feet of depth change, and suffered a gas embolism.
I've personally seen it happen in less than a meter. A colleague of mine was on surface-supplied air at about 25 feet, squatted down to pick up a heavy object on the bottom, held her breath when she stood up with the object, maybe 2 1/2 feet of depth change, and suffered a gas embolism. That was in relatively shallow water, which makes a difference as @Akimbo pointed out.
Best regards,
DDM
Depth is irrelevant here.
Roughly speaking, pressure times volume is constant. Half the pressure twice the volume. This is why bubbles are a problem indeed. Ascent from 1m or 1.1 ATM to 1.0 ATM is a very small relative pressue change. Hence, lung expansion will be minimal!
It is easy to understand how a 1.1124 PSI or 0.0767 Bar pressure difference is enough to over-pressure the lung but the volume change would require her to be significantly hyper-inflated before standing up. I have to wonder if she had an undetected tissue weakness that failed.
Have you ever heard of an AGE caused by voluntary lung-packing that is still commonly done by freedivers? I was never a fan of lung-packing since it takes time and energy to complete for a very marginal increase in volume.
I wonder if straining to lift the heavy object contributed--perhaps in a major way.
The easy way to achieve the same is to go ~86cm below the surface (body horizontal) and breathe in completely from your scuba regulator . If you hold your breath and surface, your lungs likely won't be damaged.