2w ago

15 seconds without oxygen seems low

I reread Mothership’s Player Survival guide and it struck me as odd that it says that “in space you can last 15 seconds without oxygen before falling unconscious”.

And it seems very low. Maybe the key is that it’s only if you are in space? In the cold, vacuum space? Of course I couldn’t help myself and tried holding my breath for 30 seconds and it was very easy with an atmosphere. And I’m no astronaut, athlete, nor scuba diver.

I’m thinking about houseruling that if you’re able to at least take a ~~deep breath~~ few short breaths to oxygenate and then let go beforehand, you should add a number of seconds equal to your Body save. And any previous training would add an advantage.

Does that seem reasonable?

12 comments

Not a specialist but you don’t want to take a deep breath before going into hard vacuum. The air in your lungs will try to get out and break membranes and blood vessels which will kill you.
Our bodies rely on external pressure to not deform itself and kill us in the process, we’re really « well build » for our environment
15 seconds in hard vacuum seems plausible to me but for Mothership TTRPG the rule should be « whatever make a good story »
- Thanks for the reminder. I still remember people talking about the “realistic” scene in Titan AE, where the protagonist expels the air from his lungs before venturing into space.
  Anyway, maybe I can fix it and say that you can take a few short breaths to oxygenate and then let go.
  
  I think that’s the point, you cannot oxygenate your blood.
  As a DM I’d make stress test each round on a, maybe, 6 segments clock and a move test at disadvantage. If you fail your stress test it cost you 2 segments and you make your move at disadvantage.
The low pressure causes the gasses to leave your blood, rapidly deoxigenating it; leading to hypoxia and death shortly later. It seems no animal has ever survived more than 90 seconds of vacuum exposure.
This page talks about it:
https://en.wikipedia.org/wiki/Effect_of_spaceflight_on_the_human_body#Vacuum
- Other than the Tardigrades of course.
  
  Those cocky bastards
- Thanks for the link. I’d forgotten about this. Of course, I’ve only read it phrased in the scenarios where scuba divers resurface too fast.
  I guess my proposed solution only works within a pressurized environment.
OP, you should check this video out. It's about what happens when planes depressurize and why you need to put your mask in first before helping others. https://youtu.be/kUfF2MTnqAw
Falling unconscious in 15 seconds is not only realistic, it's generous. Dying in 15 seconds seems more correct. Because this isn't low pressure, this is a vacuum!
Now, what makes sense in a game and what's fun to play around, that's different. I'm not saying you should make it so you die in 15 seconds lol. Only sharing this since you seemed to believe longer was realistic.
- Yeah, I guess I was just completely disconnected on the real hazard of depressurization. It’s not just about holding your breath.
  The worst part is that I have read about this stuff in several contexts. Maybe it’s just that it’s not a common part of my life.
  
  Yes, it's rare for one to find themselves in the vacuum of space lol so it makes sense you wouldn't have the intuition baked in.

12 comments