# Sleeping in a closed car w/ the engine off. Can you run out of oxygen? **URL:** \ **Category:** Factual Questions\ **Created:** [December 18, 2011, 6:28am UTC](https://boards.straightdope.com/t/sleeping-in-a-closed-car-w-the-engine-off-can-you-run-out-of-oxygen/606626 "2011-12-18T06:28:30Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [December 18, 2011, 6:28am UTC](https://boards.straightdope.com/t/sleeping-in-a-closed-car-w-the-engine-off-can-you-run-out-of-oxygen/606626/1 "2011-12-18T06:28:30Z")
Just curious. If you fall asleep in a car with the engine off and the windows all the way up can you eventually use up all the oxygen in the air and asphyxiate yourself if you are asleep long enough or are cars designed not to let this happen? True, but I’ve seen cars (granted this was 30 years ago) with windows burst out in the summer due to internal air pressure pushing outward on the windows. how could this happen if the car was not relatively airtight? ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [December 18, 2011, 9:05am UTC](https://boards.straightdope.com/t/sleeping-in-a-closed-car-w-the-engine-off-can-you-run-out-of-oxygen/606626/2 "2011-12-18T09:05:54Z")
> [@astro](#): > > True, but I’ve seen cars (granted this was 30 years ago) with windows burst out in the summer due to internal air pressure pushing outward on the windows. how could this happen if the car was not relatively airtight? It didn’t happen. Cars aren’t air tight. ---
**Author:** ![CutterJohn](https://avatars.discourse-cdn.com/v4/letter/c/91b2a8/32.png) [@CutterJohn](https://boards.straightdope.com/u/CutterJohn)\ **Post date:** [December 18, 2011, 12:36pm UTC](https://boards.straightdope.com/t/sleeping-in-a-closed-car-w-the-engine-off-can-you-run-out-of-oxygen/606626/3 "2011-12-18T12:36:54Z")
> [@astro](#): > > True, but I’ve seen cars (granted this was 30 years ago) with windows burst out in the summer due to internal air pressure pushing outward on the windows. how could this happen if the car was not relatively airtight? Thats from heat, not air pressure. Happens when the window is tightly shut while its cold, then it heats up. The glass expands a bit, has nowhere to go, and that can cause it to break. Since side windows are tempered glass, when it goes it _really_ goes. Seems to be a lot less common now. Better glass maybe, or possibly a more flexible frame. ---
**Author:** ![Mr.Accident](https://avatars.discourse-cdn.com/v4/letter/m/f05b48/32.png) [@Mr.Accident](https://boards.straightdope.com/u/Mr.Accident)\ **Post date:** [December 18, 2011, 1:25pm UTC](https://boards.straightdope.com/t/sleeping-in-a-closed-car-w-the-engine-off-can-you-run-out-of-oxygen/606626/4 "2011-12-18T13:25:49Z")
Within the last month or so my girlfriend and I slept in the back of her Isuzu Rodeo with the windows up. We didn’t asphyxiate. At least I don’t think we did. There’s the possibility that we’re highly cognitive zombies who crave pizza instead of human flesh, but I don’t think that we are. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [December 18, 2011, 1:39pm UTC](https://boards.straightdope.com/t/sleeping-in-a-closed-car-w-the-engine-off-can-you-run-out-of-oxygen/606626/5 "2011-12-18T13:39:56Z")
I approve of this new-style zombie. ---
**Author:** ![Gfactor](https://avatars.discourse-cdn.com/v4/letter/g/9de053/32.png) [@Gfactor](https://boards.straightdope.com/u/Gfactor)\ **Post date:** [December 18, 2011, 3:09pm UTC](https://boards.straightdope.com/t/sleeping-in-a-closed-car-w-the-engine-off-can-you-run-out-of-oxygen/606626/6 "2011-12-18T15:09:09Z")
Closing this thread as a duplicate of this one: [Sleeping in a closed car w/ the engine off. Can you run out of oxygen? - Factual Questions - Straight Dope Message Board](http://boards.straightdope.com/sdmb/showthread.php?t=635356) Nothing more to see here.