3 minutes without oxygen. 3 days without water. 3 weeks without food (I think it is also “3 hours without shelter” but that is a much more environmental factor and feels shoehorned in). And, depending on the apocalypse, clean air can be hard to come by.
Yeah, obviously need the first that that will kill you. We take breathable air for granted. But if you need an infinite supply of clean air, you are probably dead anyway.
An infinite supply of water has many uses beyond drinking and hygine – irrigation, power, and cooling come to mind as very useful post-apocalypse.
If you are going that route: Rule of 3
3 minutes without oxygen. 3 days without water. 3 weeks without food (I think it is also “3 hours without shelter” but that is a much more environmental factor and feels shoehorned in). And, depending on the apocalypse, clean air can be hard to come by.
I’ve heard it phrased “3 hours without shelter in inclement weather”.
Yeah, obviously need the first that that will kill you. We take breathable air for granted. But if you need an infinite supply of clean air, you are probably dead anyway. An infinite supply of water has many uses beyond drinking and hygine – irrigation, power, and cooling come to mind as very useful post-apocalypse.