maximum lung pressure

[ages]

Not sure if this belongs under diving medicine, but it seemed the logical place to be.

What is the accepted value for maximum lung pressure? We are doing a report on the affects of ocean swells and holding your breath while diving. We want to show how easy it is to exceed the "maximum lung pressure.

ages

 

[BillP]

Hi ages:

The important number isn't the total pressure in the lung but rather the difference in perssure between inside the lung and outside the lung. If the pressure in the lung is 95-110 cm H2O higher than the pressure outside the lung, the lung can rupture.

(100cmH2O= 0.097ATA= 0.098bar= 1.42PSI= 73.55mmHg approx.)

HTH,

Bill

 

[Dr Deco]

Hi ages:

[sp]Please note that this pressure difference mentioned by BillP is only about three feet of water. Children breathing from a bucket underwater in a swimming pool have suffered lung rupture with a about this difference. They took a breath from the submersed bucket [at four feet] and held that breath to the surface of the pool. Regrettably in the case with I am familiar, the child died.
__________
Dr Deco

 

[ages]

Thanks!! We want to simply show how easy it is to exceed the amount of pressure the lungs can handle. So, if you are in the inhale/pause phase of breathing, a 3 foot vertical surge is all that is needed to go blamo (technical term for really big lungs with holes in them)!!

ages

 

[Dr Deco]

Ages:

If you are connected by a line to the surface, and you ride up and down with the surge, there is no effect of pressure. If you are connected to the bottom, the surge will have a pressure effect. :devilish:

Dr Deco

 

[50sdiver]

Hay DocDeco:
I don't know if Ages or I understand correctly. I've dove in water with much more than 3' waves doing the inhale-pause-exhale thing and I've never noticed any problem.
if Ages is implying that your only a few feet down when the surge goes over thten the surge will lift you up and it's no problem. If you are deeper than that doesn't the pressure average out? Or am I being dense?
Thanks for your responce
Bob (50sdiver)

 

[Thistle]

In the case mentioned by Dr. Deco the child holds his breath until surfacing, the air from the lungs expands and cause a rupture of the organ.
This is why the for going up on emergency ascent you have to exhale, to avoid the air to expand in your lungs as the presure drops.

As I see it ages want to know what pressure the lung can bear, meaning for example how deep can you dive. As far as I remember there is the so called "100m club", people who went down 100m and came back alive. They did that using recreational diving equipment. I believe the lung as well as other organs can take up a lot of presure as long as it is balanced with the air fron inside the lung.
victor