[a / b / c / d / e / f / g / gif / h / hr / k / m / o / p / r / s / t / u / v / vg / vm / vmg / vr / vrpg / vst / w / wg] [i / ic] [r9k / s4s / vip / qa] [cm / hm / lgbt / y] [3 / aco / adv / an / bant / biz / cgl / ck / co / diy / fa / fit / gd / hc / his / int / jp / lit / mlp / mu / n / news / out / po / pol / pw / qst / sci / soc / sp / tg / toy / trv / tv / vp / vt / wsg / wsr / x / xs] [Settings] [Search] [Mobile] [Home]
Board
/sci/ - Science & Math

File: images.jpg (9 KB, 280x180)
9 KB JPG
Say I'm alone in a sealed space without any air coming in. About big would the space need to be for me to survive 12 hours?
>>
Anon what are you planning? Don't. I'm calling the police.
>>
>>14734535
I'm writing a short story where a character is trapped underground and has to contemplate murdering another character in order to preserve more oxygen for himself.
>>
>>14734539
In that case the oxygen will be the less of a problem. The air is 21% oxygen, but a CO2 concentration of 1% will already make you drowsy.
https://en.wikipedia.org/wiki/Hypercapnia
>>
>>14734570
Got it. Can you give me a ballpark estimate of how big a volume of air you'd need to survive for 12 hours without dying from excessive CO2?

Of course it'd vary from person to person, but I'm just after a ballpark estimate. I appreciate your time.
>>
>>14734586
Is it only 2 people down there?
>>
>>14734590
Yes. The character's thought process is, "It could take them 12 hours or more for us to be rescued. That means my odds of survival would go way up if the other person in the space with me were dead." So I'm looking for a volume that would allow one person (not two) to plausibly survive for 12 hours.
>>
>>14734598
What percentage causes which effect is listed in Wikipedia.
According to a quick Google search, a human exhales 500 Liters of CO2 per day, so do 2 people in 12 hours. Let your character do the maths. What percentage is still ok? 500/(percentage) gives you the volume. If you say that it shouldn't exceed 10%, the cave can't be more than 500/0.1 Liters = 5000 Liters = 5 cubic meters. If your character draws the line at 3%, he must kill the other person if the cave is smaller than 500/0.03 Liters ~ 17 m^3
>>
>>14734629