Waterproof surface: a perk?

[Ulzgoroth]

Originally Posted by Humabout

From B82:

"You are encased in a gas- and liquid-impermeable layer. This makes you waterproof and grants complete immunity to corrosive and toxic agents that must touch skin or exposed machinery to work."

So I guess it totally makes sense that hydrofloric acid won't melt your face because the chemical reaction between to and your skin cannot take place because there is no conact being made, but water evaporating still gives you hypothermia, even if, by the logic above, the water never touches you to lower your enthalpy.

Your theory is that Sealed also means you're encased in a heat-impermeable layer?

The impermeable layer is your outer surface. The water touches and cools that, and thus you.

[Humabout]

So you are saying that Sealed encases you in a nonreactive outer layer that conducts heat perfectly but prevents conact agents from affecting you in any way? So Sealed is simply Immunity to Conact Agents [5]? I just want to be clear on what you think Sealed does.

[whswhs]

Originally Posted by Humabout

So I guess it totally makes sense that hydrofloric acid won't melt your face because the chemical reaction between to and your skin cannot take place because there is no conact being made, but water evaporating still gives you hypothermia, even if, by the logic above, the water never touches you to lower your enthalpy.

It depends. Can the water cling to you while it evaporates, or does it just run off? If there's a pool of water at your feet, its evaporation won't make you much colder. And note "sheds water like a duck's back."

[Christopher R. Rice]

Originally Posted by Bruno

The survival rules, whichever you're using, put a pretty big penalty on characters who get wet in cold conditions (and rightly so).
There are a lot of animals who have a surface covering designed to either separate themselves from the water, shed water rapidly, or both. Obviously they partly include some Temperature Tolerance (cold), but I'm thinking of a trait that exempts you from the "wet" penalty, at least as long as your fur/feathers are in good condition.

With the "natural" limitations (doesn't work if ruffled or dirty), a perk seems fine. What I'm having a little more difficulty eyeballing is if you don't have those natural limitations. Perhaps you have a skin-hugging force-field bubble.

It's a perk. See the Umbrella perk from GURPS Psionic Powers (p. 56) for a canonical example.

Originally Posted by Bruno

In related questions, does Sealed include ignoring the wet penalty among its benefits?

I'd say yes.

[Ulzgoroth]

Originally Posted by Humabout

So you are saying that Sealed encases you in a nonreactive outer layer that conducts heat perfectly but prevents conact agents from affecting you in any way? So Sealed is simply Immunity to Conact Agents [5]? I just want to be clear on what you think Sealed does.

It doesn't say anything about providing thermal insulation. A zip-lock bag is Sealed. If you want thermal protection you take other traits, as clearly

I'm pretty sure it includes Filter Lungs protection against respiratory agents as well.

Characterizing it as Filter Lungs [5] + Immune to Contact Agents [10] doesn't seem far wrong.


EDIT: Tangential, but is Sealed actually supposed to make you totally immune to reactive chemistry? Because that would make the trait almost perfectly useless for modeling anything, but it's not really clear. Either there isn't a trait to cover 'I can bathe in chlorine trifluoride' or nobody who can't do that has Sealed...

[evileeyore]

Originally Posted by Ulzgoroth

Either there isn't a trait to cover 'I can bathe in chlorine trifluoride' or nobody who can't do that has Sealed...

Immune to Metabolic Hazards would cover that just fine.

[Ulzgoroth]

Originally Posted by evileeyore

Immune to Metabolic Hazards would cover that just fine.

Um, no. Most inanimate objects will burn and corrode on contact with that.

[Bruno]

Is that the one that oxidizes steel, glass, sand, and test engineers? Barely sits in aluminum containers because it forms some sort of aluminum fluorine oxygen compound but good help you if you scratch or dent it?

[Phantasm]

Originally Posted by Ulzgoroth

Either there isn't a trait to cover 'I can bathe in chlorine trifluoride'

Originally Posted by evileeyore

Immune to Metabolic Hazards would cover that just fine.

Originally Posted by Ulzgoroth

Um, no. Most inanimate objects will burn and corrode on contact with that.

Indeed, most acids aren't considered "metabolic" hazards the way poisons, diseases, and environmental syndromes are; most do cyclic corrosive damage on contact. You'd need some form of DR to protect against that (I'm going to assume ceramics like glass for that), and a there's plenty of things that provide DR that also provide Sealed. (Also a lot of things that provide DR that don't provide Sealed, too, like leather.)

[Anders]

Originally Posted by Bruno

Is that the one that oxidizes steel, glass, sand, and test engineers? Barely sits in aluminum containers because it forms some sort of aluminum fluorine oxygen compound but good help you if you scratch or dent it?

Steel, copper or nickel vessels. Seriously nasty stuff.