# can you tell if you walk into a room with just nitrogen **URL:** \ **Category:** Factual Questions\ **Created:** [July 3, 2011, 5:08am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688 "2011-07-03T05:08:54Z")\ **Posts on this page:** 12\ **Page:** 2
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [July 3, 2011, 9:46pm UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/21 "2011-07-03T21:46:10Z")
> [@Chronos](#): > > Are there any sensors that can detect a dangerously low oxygen level, that could be hooked to an alarm in places that use liquid nitrogen? Canaries ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [July 3, 2011, 10:36pm UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/22 "2011-07-03T22:36:40Z")
[Limnic eruptions](http://en.wikipedia.org/wiki/Limnic_eruption) are another example of how dangerous large concentrations of CO2 can be. Wandering Wikipedia, I see that there’s actually a geologic term for pockets of dangerously oxygen poor air: [mazuku](http://en.wikipedia.org/wiki/Mazuku). “Evil wind” in Swahili. ---
**Author:** ![wbeaty](https://avatars.discourse-cdn.com/v4/letter/w/439d5e/32.png) [@wbeaty](https://boards.straightdope.com/u/wbeaty)\ **Post date:** [July 4, 2011, 3:00am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/23 "2011-07-04T03:00:51Z")
> [@user\_hostile](#): > > You know how your nose burns when you burp up the CO2 from a bottle of soda? It’s much, much worse…think of it as a gaseous water boarding. We kill enormous numbers of animals daily using CO2. I’ve talked to people doing this. Universally they believe that it’s painless. The boss said it’s painless. The literature says it’s painless. I tell them to try it briefly themselves. They simply refuse to believe that so many people are killing animals painfully, and that nobody knows about this. [CO2 euthanasia test: yes causes pain/distress](http://www.slideshare.net/guest48f481/pain-and-distress-during-co2-euthanasia-357399) ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [July 4, 2011, 3:11am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/24 "2011-07-04T03:11:27Z")
In addition to the pain, the article I linked to above says that high CO2 levels cause uncontrollable lung spasms. Your body will start coughing wildly in an attempt to drive the CO2 out of your lungs. The researchers had to use special mixtures of gas to eliminate this spasm reflex during their tests. ---
**Author:** ![wbeaty](https://avatars.discourse-cdn.com/v4/letter/w/439d5e/32.png) [@wbeaty](https://boards.straightdope.com/u/wbeaty)\ **Post date:** [July 4, 2011, 3:16am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/25 "2011-07-04T03:16:39Z")
> [@JWT\_Kottekoe](#): > > It would be a very pleasant way to die. You simply fall asleep with no discomfort. But not without prompt symptoms. At a party as I kid I was trying to speak with much higher pitch in “helium speech.” So I emptied my lungs as much as I possibly could. Then I inhaled from a He balloon while trying not to suck in any outside air at all. Within about five seconds I heard roaring “jet planes” approaching from behind me. “Black Sparklies” started encroaching on my peripheral vision, leaving a central patch of vision which became more and more narrow. I had to grab the table to keep from falling over. By panicked violent breathing, I made the “tunnel vision” open out again, and the roaring-squeal tinnitus seemed to move off into the distance behind me. I expect that “Helium Blackout” is probably identical to “N2 blackout.” Also, I once fainted during a long blood draw. Symptoms were identical to the above, but also I tried to say “you better take it out” as I was falling over, but it came out “Yubbbtoodduuu.” So slurred speech yes. Nightmare of syringe needle broken off inside artery. Oh, also it’s interesting to wake up after fainting. It feels exactly like waking up after many hours of sleep. You know it must be morning. But there’s a giant plane of linoleum pressed against your face. With white med workers’ shoes glued to it. With legs sticking sideways out of the shoes. I guess the classic “where am I” question instead is really this one: “It’s obviously morning and I’m just waking up after a full night’s sleep, so how did all you people get into my bedroom. Wait a minute, this isn’t my bedroom. It looks like a doctor’s office. I went to the doctor, was it days ago? Yesterday? Hey, I don’t remember coming home! What day is it anyway? Hey, WHERE AM I?” ---
**Author:** ![code\_grey](https://avatars.discourse-cdn.com/v4/letter/c/f4b2a3/32.png) [@code\_grey](https://boards.straightdope.com/u/code_grey)\ **Post date:** [July 5, 2011, 6:23am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/26 "2011-07-05T06:23:24Z")
> [@wbeaty](#): > > We kill enormous numbers of animals daily using CO2. > > I’ve talked to people doing this. Universally they believe that it’s painless. The boss said it’s painless. The literature says it’s painless. I tell them to try it briefly themselves. > > They simply refuse to believe that so many people are killing animals painfully, and that nobody knows about this. > > [CO2 euthanasia test: yes causes pain/distress](http://www.slideshare.net/guest48f481/pain-and-distress-during-co2-euthanasia-357399) so do you think they should they switch to killing animals using nitrogen instead? Or is nitrogen significantly more expensive than CO2? ---
**Author:** ![code\_grey](https://avatars.discourse-cdn.com/v4/letter/c/f4b2a3/32.png) [@code\_grey](https://boards.straightdope.com/u/code_grey)\ **Post date:** [July 5, 2011, 6:28am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/27 "2011-07-05T06:28:10Z")
if a person dies from exposure to nitrogen atmosphere, will examination of the corpse readily determine the cause of death? Or is the pattern of damage from this similar to some other causes of death, so that there would be no certainty as to the true reason? ---
**Author:** ![clairobscur](https://avatars.discourse-cdn.com/v4/letter/c/839c29/32.png) [@clairobscur](https://boards.straightdope.com/u/clairobscur)\ **Post date:** [July 5, 2011, 7:54am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/28 "2011-07-05T07:54:22Z")
> [@code\_grey](#): > > if a person dies from exposure to nitrogen atmosphere, will examination of the corpse readily determine the cause of death? Or is the pattern of damage from this similar to some other causes of death, so that there would be no certainty as to the true reason? Someone you’d want to get rid of? 😉 ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [July 5, 2011, 8:40am UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/29 "2011-07-05T08:40:30Z")
> [@code\_grey](#): > > if a person dies from exposure to nitrogen atmosphere, will examination of the corpse readily determine the cause of death? Or is the pattern of damage from this similar to some other causes of death, so that there would be no certainty as to the true reason? It’ll be suffocation, but without the signs of violence that might accompany strangulation, smothering, etc. ---
**Author:** ![Enilno](https://avatars.discourse-cdn.com/v4/letter/e/58f4c7/32.png) [@Enilno](https://boards.straightdope.com/u/Enilno)\ **Post date:** [July 5, 2011, 3:44pm UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/30 "2011-07-05T15:44:11Z")
> [@Little\_Nemo](#): > > Nor did I. > > What happens if you’re in an atmosphere that’s 20% oxygen and 80% carbon dioxide? Will the high CO2 level around you prevent you from getting rid of CO2 in your lungs and cause you to suffocate even though there’s a breathable amount of oxygen? According to this [MSDS sheet](http://www.uigi.com/MSDS_gaseous_CO2.html), CO2 would be lethal at far lower concentrations: > [@](#): > > Carbon Dioxide is a powerful cerebral dilator. At concentrations between 2 and 10%, Carbon Dioxide can cause nausea, dizziness, headache, mental confusion, increased blood pressure and respiratory rate. Above 8% nausea and vomiting appear. Above 10%, suffocation and death can occur within minutes. ---
**Author:** ![Chessic\_Sense](https://avatars.discourse-cdn.com/v4/letter/c/7c8e57/32.png) [@Chessic\_Sense](https://boards.straightdope.com/u/Chessic_Sense)\ **Post date:** [July 5, 2011, 5:14pm UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/31 "2011-07-05T17:14:26Z")
As **wbeaty** describes, inhaling CO2 or nitrous oxide first causes the ears to wring awfully loud, like there are high-pitched planes buzzing around your head. Then the dizzyness and unconsciousness comes. You’ll hit the floor but you won’t feel it until later. You’ll feel dissociated, like you’re floating out of your body or like your limbs aren’t attached properly. You’ll seem to simultaneously float through the air and sink like rock. Should the cat happen to begin pawing at you interestedly, she’ll feel like she’s 10 cats with a million paws each, poking you all over. Oh, and it’ll seem hilarious at the time, but will seem incredibly stupid and dangerous 10 years later. Not that I’d know what a [whippet](http://en.wikipedia.org/wiki/Whippit) was like, or anything… ::shifty eyes:: As for a stopped heart, anyone that’s ever had a proper [blood choke](http://en.wikipedia.org/wiki/Chokehold#Blood_choke) done on them can attest that it’s certainly lights-out in seconds…no more than 3, I’d say. ---
**Author:** ![code\_grey](https://avatars.discourse-cdn.com/v4/letter/c/f4b2a3/32.png) [@code\_grey](https://boards.straightdope.com/u/code_grey)\ **Post date:** [July 5, 2011, 8:42pm UTC](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688/32 "2011-07-05T20:42:26Z")
> [@Mangetout](#): > > It’ll be suffocation, but without the signs of violence that might accompany strangulation, smothering, etc. when people die because their heart stopped for no clear reason, does that also look like “suffocation but without the signs of violence”? Or are there distinct features in “death from heart failure” to separate it from “death from no oxygen in the air”? [Previous page](https://boards.straightdope.com/t/can-you-tell-if-you-walk-into-a-room-with-just-nitrogen/587688.md?page=1)