Amounts of pressure within 33 ft?

[RJP]

Do big fat divers expereince more pressure because they have more surface area? Also, if you lay flat, do you feel more pressure since their is more water above you than if you stand in a vertical position? Is that why PADI wants their students to kneel...so that they get less pressure and absorb less nitrogen?

I wear a cone-shaped hood so all that pressure just runs right off me!

 

[dumpsterDiver]

I wear a cone-shaped hood so all that pressure just runs right off me!

I've seen something similar on submarines and dive scooters, now I knw why. Thanks!

 

[dmcutter]

Do you feel less pressure in a thicker wetsuit because it absorbs the pressure as it compresses, sort of a sacrificial anode kind of thing?

 

[DevonDiver]

Yes, the kneeling position is clinically proven to reduce the head-ass gas gradient, thus decreasing the risk of the infamous 'foot bend'.

Other famous issues caused by pressure are domestic fires, divorce and homelessness. It is not clear from the article, below, at what PSI those dangers can manifest....

Mm ba ba de
Um bum ba de
Um bu bu bum da de
Pressure pushing down on me
Pressing down on you no man ask for
Under pressure - that burns a building down
Splits a family in two
Puts people on streets
​

 

[Kern]

Do you feel less pressure in a thicker wetsuit because it absorbs the pressure as it compresses, sort of a sacrificial anode kind of thing?

No, you feel the same pressure no matter what thickness the wet suit.

As the water inside the wet suite is exerting the same pressure in every direction as the water outside the suit, you may feel the suit constriction relax though.

 

[eXile]

Do big fat divers expereince more pressure because they have more surface area? Also, if you lay flat, do you feel more pressure since their is more water above you than if you stand in a vertical position? Is that why PADI wants their students to kneel...so that they get less pressure and absorb less nitrogen?

No, fat divers and skinny divers (and all those inbetween) feel the pressure the same.
Remember, were talking about .5 psi per foot, you get more change in a storm above than a foot of water.

PADI Kneeling is for comfort, and saftey. If you are kneeling in a circle, and something happens, the student (or instructor) can "lunge" forward. Also, kneeling reduces the damage on the sea floor, in comparison to laying horizontal which is awkward, and standing, where your fins do more damage. More stable, more environment. And its comfy.

 

[ItsBruce]

While the technical answers are all pretty much correct, the easy and accurate answer is:

No. The pressure increases s linearly. At 33 feet the pressure has increased to the point that it has doubled from what it was at the surface.

 

[DevonDiver]

No, fat divers and skinny divers (and all those inbetween) feel the pressure the same.

Fat people often sweat more. As we know - pressure increases with temperature if volume is constant. Therefore, fat people of static volume suffer more pressure. However, if they expand....then the water pushed back with equal an opposite force - adding the force of expansion to the ambient pressure.

It's science. Fact!

PADI Kneeling is for comfort, and saftey.

Is that a speciality course?

If you are kneeling in a circle, and something happens, the student (or instructor) can "lunge" forward.

My students just love it when I "lunge" at them. If proper buddy procedures are followed, they should "lunge" back. Double-lunge or group lunge (if you follow DIR and team diving principles).

Also, kneeling reduces the damage on the sea floor, in comparison to laying horizontal which is awkward, and standing, where your fins do more damage. More stable, more environment. And its comfy.

So...kneeling is better than standing, because the knees cause less damage to marine life than the fins? Wouldn't 'spreading' the weight cause less pressure?

When I want to rest myself on a soft coral, anemone or sea urchin....I try and spread my weight over it as much as possible. I find that the marine life is more thankful if I do that. comfy enviroment science you see?

I do agree though... being horizontal is just plan awkward. It should be avoided at all times. If you are upright, then you can use your fins to kick powerfully and keep yourself off the bottom without the need to rely on a BCD. It's 'comfy science'. It's more environment. Less global warming and fossil fuels that way.

 

[Hickdive]

I thought PADI had incorporated the "Irony and Humor (sic)" speciality into the OW course nowadays?

Got to get me one of them conical hoods though.

 

[DevonDiver]

Here's the cone hood in action...

The diver has made the mistake of being horizontal...which as eXile pointed out, is awkward and unstable. They've deployed their octopus in a 'stability role' to compensate... which is a good work-around to that common problem...