I did the calcs and then had my girlfriend code it into a website.

All the dimensions are in feet.

http://equireg.com/random/suffocate.php

I'm fairly sure I did the calculations right.

I assumed that one would need to use up the entire supply of air in the room. Found averages of 500 cubic centimeters per average breath and an average of 12 breaths per minute online, converted, and went from there.

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Proud LGBTQQ Individual

hm...I dont believe you'd be able to use up all the oxygen in the room, wouldnt you pass out and die before it is all used up? It's not like you'll be using discrete 'chunks' of oxygen, it's going to continually diffuse to less dense areas, so the overall density of o2 will simply lessen with each breath. Not that i'm some oxygen scientist or something. There must be some threshold of oxygen content which a person must have to 'get a breath' from it, and below that = death.

You would pass out due to CO2 intake, but while passed out you will still be breathing, so eventually you will die from no Oxygen in the air.

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If you made the assumption that each inhalation/exhalation would use up all O2 in that breath, that's going to be wrong. Only about 5% of O2 inhaled on each breath is actually consumed.

Hm, interesting, where do you learn something like that?

<- Retired EMT.

Came here to say that.

There are other bad assumptions here too.
"Air" is mostly nitrogen (almost 80%) and only about 20% oxygen.
When you exhale, it's not pure CO2...and what you need to measure to determine suffocation is the CO2 levels, not the oxygen levels.

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Hold my beer and watch this...

I do know that there is oxygen in exhaled breath. Internet searching revealed the percentage was just below the necessary oxygen content for breathable air. So my assumption was that each breath takes 500cc of breathable air and replaces it with 500cc of unbreathable air. I basically left this as is because I found too much conflicting information on the internet to be able to know for sure.

I would like to see an amended calculation from those that have more information. The big averages to know are:
500 cubic centimeters per normal breath
12 breaths per minute on average

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Proud LGBTQQ Individual

Wow, I swear my wife must take like 40 breaths per minute. This number surprised me.

So, you want to know these numbers because you're planning on killing someone by "accidentally" shutting them into an air-tight room?

I was wondering how long I could survive in my bathroom.

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Proud LGBTQQ Individual

Don't do it!!! You're so young!!!!! You have so much to live for!!!!!!

But your bathroom isn't airtight, and I would bet my life savings on that.

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Does it need to actually be 'airtight' though? If the holes are small enough, and there isnt a large pressure gradient between the two spaces I don't think enough air would move through the hole to save someone if they're on the cusp of asphyxiation.

As long as about 25cc or so of O2 is entering the room for each breath a person takes, that's enough.

Ahh, but a pressure gradient would surely be caused by temperature differences...unless you keep your house at 98.6 degrees.

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Hold my beer and watch this...

Ah, but heating the area INSIDE the box would cause a higher pressure inside the room, and result in a net efflux of air.

So put a candle inside the bathroom, which would do a double job of creating positive pressure and burning oxygen

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Hold my beer and watch this...

lol...and here I was thinking we're trying to stay ALIVE in said 'bathroom of horrible choking asphyxia'.

Also known as 'The morning after a Super Mighty Pack at 3am'.

I approve of the level of geek in this thread.

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