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Kaelaroth
2008-02-15, 09:37 AM
OK, forgive me if I've mixed up the science in this question somewhere. I have been taught that we, as humans, have adapted to the air pressure on Earth. If we went somewhere where there is higher pressure, we're crushed, but in space, where there is no pressure, we explode (or burst).

So, one would assume that creatures on the Elemental Plane of Water have grown accustomed to far higher pressure that we have, right?

So my questions are:
1. Are you instantaneousluy crushed if you shift to the Elemental Plane of Water with protection?
2. Can you kill creatures from the Elemental Plane of Water by teleporting them onto the Material Plane (or similarly low pressure plane), and wait for them to explode?

Apologies if this question has been asked before.

MorkaisChosen
2008-02-15, 09:39 AM
That's an interesting one, but Plane of Water has subjective gravity, doesn't it? If yes, we can assume that it has similar pressure to the PMP, since there could just be the right amount of space to make it the same pressure. With objective gravity, dunno.

UglyPanda
2008-02-15, 09:43 AM
We don't explode, we inflate. Not nearly enough pressure in the human body to explode, even in a vacuum.

1. It depends on the composition of the elemental plane of water. If it all has as much pressure the Mariana Trench, of course you're going to die. It it's as much pressure as scuba diving or snorkeling depth (Both of which have no added protection), then you're fine so long as you don't sink and can still breathe.

2. Blowfish don't explode. If anything, fish have even less internal pressure in their bodies.

Sofaking
2008-02-15, 09:48 AM
Easy answer. No. They will suffocate but they will not explode. Fish don't just start exploding when you pull them out of water. Rare, deep sea living creatures will but I believe their native plane would be the Material plane. I would figure from the books that pressure is constant throughout the plane and that pressure is not enough to kill a person (It dosen't have to make sense).

daggaz
2008-02-15, 09:55 AM
You die from your bodily fluids boiling in a vacuum (no pressure means the suspended gases bubble out, and liquid water goes to gas albeit without the heat commonly associated with boiling), basically your blood stops working and you have a giant stroke/case of the bends.

Deep sea fish (like the red snapper) dont explode when they come to the surface, but their swim bladders hyperinflate and usually pop out of their mouths, killing them. Really deep sea creatures, like the dragonfish, dont have swim bladders, but they die from the depressurization in much the same manner as we do in a vacuum.

Gravity on the elemental planes is subjective and there is no reason really to start tossing catgirls at your players, they shouldnt be effected by any kind of pressure problems unless you really want to add that dimension to your game.

daggaz
2008-02-15, 09:58 AM
You die from your bodily fluids boiling in a vacuum (no pressure means the suspended gases bubble out, and liquid water goes to gas albeit without the heat commonly associated with boiling), basically your blood stops working and you have a giant stroke/case of the bends.

Deep sea fish (like the red snapper) dont explode when they come to the surface, but their swim bladders hyperinflate and usually pop out of their mouths, killing them. Really deep sea creatures, like the dragonfish, dont have swim bladders, but they die from the depressurization in much the same manner as we do in a vacuum.

Gravity on the elemental planes is subjective and there is no reason really to start tossing catgirls at your players, they shouldnt be effected by any kind of pressure problems unless you really want to add that dimension to your game.

bbugg
2008-02-15, 11:33 AM
Agreed, daggaz. Fish that get sucked into hydropower turbines die by rapid decompression.
I don't think you even need a terribly high pressure difference, it's the (de)compressiong RATE that matters.
I also agree that there's no need to bring this into D&D unless you really want to.

Chronos
2008-02-15, 05:04 PM
You die from your bodily fluids boiling in a vacuum (no pressure means the suspended gases bubble out, and liquid water goes to gas albeit without the heat commonly associated with boiling), basically your blood stops working and you have a giant stroke/case of the bends.Although this will eventually happen with any exposed liquids, there really isn't that much exposed liquid on the human body. You'll die of suffocation long before the pressure would have any significant effect on you. The correlary is that if you're exposed to vacuum for a short enough time that you can go without breathing, you'll be (more or less) fine when you get back in your ship.

Roderick_BR
2008-02-15, 09:56 PM
Does D&D even have rules for pressure? I remember someone once said that for all we know, a wizard could teleport to the bottom of the ocean with a pearl of sirines, rest, then come back with silent teleport, and memorize his daily allotment, since, by RAW, nothing says you get any penalty by high pressure.

FlyMolo
2008-02-15, 10:28 PM
DnD has crushing damage, but no other rules for pressure.

In any case, the Elemental Plane of Water has subjective gravity. Therefore, no real pressure, because the gravity doesn't build up enough pressure.

Same idea on the EPoA.

I think Fire and Earth have structure, no?

sickler
2008-02-15, 10:56 PM
In a game as magical and surreal as DnD, do you really want to restrict your players on not going to the Elemental Plane of Water just because they didn't bring a diving suit?

You can implement it as a house rule if you want though.

TheOOB
2008-02-15, 11:41 PM
Lets make this simple:

Magic Doesn't Work Like That.

Magic does what it says it does, regardless of the laws of physics, in fact by definition magic breaks the laws of physics. A character doesn't get hurt from pressure in the elemental plane of water because it's magic, it does follow any real laws, it's just an infinite expanse of water, which alone is impossible.

daggaz
2008-02-16, 06:21 AM
Although this will eventually happen with any exposed liquids, there really isn't that much exposed liquid on the human body. You'll die of suffocation long before the pressure would have any significant effect on you. The correlary is that if you're exposed to vacuum for a short enough time that you can go without breathing, you'll be (more or less) fine when you get back in your ship.

Umm what? While exposed liquids react first (the liquid on your eyes immediately begins to boil AND freeze), your entire body does indeed feel the difference in pressure. You no longer have 14 lbs per square inch pressing down on every bit of your skin, and things...expand. This does results in capillary expansion and destruction (bruising), tissue damage in the lungs if you try to hold your breath, as well as "the bends." Scientific testing of rapid depressurization indicates that you have about 30 seconds before loss of consciousness due to effects on your brain. Its highly reccommended to keep your eyes and mouth closed and to expel any air in your lungs first..

As for whoever mentioned fish going thru hydroelectric turbines.. umm... where did that come from? Those guys die from either getting whacked by the blades, or from being shaken too much (fish are so easily killed). Smaller fry often make it through alive..

Anyhow, pain in the butt to add gravity problems to the plane of water. Just add horrible underwater creatures instead, if you want to make life miserable for your party.

Subotei
2008-02-16, 08:16 AM
I found this once when looking for some info for a sci-fi game I was in - effects of vacuum exposure on humans. Off topic - so apologies - but interesting.

http://www.sff.net/people/Geoffrey.Landis/vacuum.html