5 HN users recommended this demo5 months2016–2025score 5.5
Years with an HN recommendation, 2007–2026
It is the go-to demonstration of how hypoxia silently disables decision making, cited in threads on altitude, flying, diving, CO2 and breathwork.
Destin Sandlin of Smarter Every Day undergoes hypoxia training and experiences his own impaired thinking as oxygen is withdrawn. The video shows how quickly and unnoticeably oxygen deprivation degrades judgment, illustrating why you put your own mask on first.
“has a wonderful video demonstrating this effect [0]. I’d recommend watching the whole thing” (HN, 2025)
Destin from Smarter Every Day (YouTube) has a wonderful video demonstrating this effect [0]. I’d recommend watching the whole thing, but you can see how much of an effect it has starting around the 6:00 mark. [0] [this video]
Wonderful demonstration of hypoxia effects, worth watching in full.
This Smarter Every Day video demonstrates how dumb you can get under (less mild) hypoxia (and why it's important to take care of your own oxygen mask before others') [this video]
Destin from the 'Smarter Every day' YouTube channel did something similar (in a PSA-sort of style), and it's partly funny, partly scary to watch: [this video]
30-40k ft is absolutely a problem. Even if you remain conscious, you're completely unable to think coherently and generally have no idea what you're doing. Stay there long enough and you will unquestionably suffer brain damage and probably death as well. SmarterEveryDay did a good video about hypoxia training that demonstrates the very rapid onset and severe effects of hypoxia at cruising altitudes: [this video]
Shows rapid, severe onset of hypoxia at cruising altitude.
Does anybody have an opinion why not to use low pressure as a method killing [0]? All the failed executions by electrical chairs and administered chemicals makes me think about a safer and more human method. Just theoretical question, not advocating for anything. [0] [this video] Edit: Typo
And we should all remember to keep our seat belts on. And also seriously you should put your mask on first quickly before helping others. Your ancestors didn't experience a lack of oxygen without excess CO2 so you'll only experience the later as feeling that you're running out of breath. Without oxygen you can become too stupid to put on your air mask[1], then black out and die without noticing something is wrong. And if you're working in a lab with a cryogenic liquid that spills don't try to be a hero, just get you and your lab-mates out of there. [1] [this video]
Hypoxia can make you too stupid to put on your mask.
Destin at Smarter Every Day shows you the effects of hypoxia and why you should put your mask on first before helping a child or other passenger. [this video]
> so that we can detect the symptoms of hypoxia particular to our own bodies Destin of SmarterEveryDay (with astronaut Don Pettit) recorded his experience with that training, which included a demonstration of the effects of hypoxia on his decision making ability. He doesn't notice the rapidly increasing symptoms: >> [Destin fails child's shape toy test, saying the cross was a square] "Alright you're starting to have a little shake there, you know from your lack of oxygen. You need to start thinking about getting back on oxygen now Destin." >> "How would you correct for that? Can you correct for hypoxia for me?" [Destin just sits looking confused] "Alright sir if you don't get on oxygen, you're going to die. Go to your regulator, get all three switches on your regulator..." [Destin looking even more confused: "I don't want to die"] >> [they get him back on O2, fixing everything in seconds] [this video]
Destin's hypoxia training shows impaired decision making.
There's an interesting caveat here, the phenomenon is well known to apnea practitioners: - Hyperventilating, then holding your breath underwater can easily be deadly. - Doing the same without hyperventilation is much safer. The difference lies in the fact that our ability to sense our limits are almost entirely due to CO2 buildup. We actually almost can't tell when we run out of oxygen, it's why pilots are fine one second and pass out the next when they don't notice that the oxygen runs out ( [this video] ). Hyperventilating reduces your CO2 but leaves oxygen saturation almost unaffected, which for an unexperienced person is equivalent to doing a blind walk next to a cliff, and removing the barrier.
Pilots pass out without noticing oxygen running out.
Oh, so it is in fact just geoblocked? That's annoying. It's still down for me (and my EU VPN). Does the site list deaths by date of report, or date of death? Hopefully the later, so we can just check back in a few weeks. Anyway, in general this "dying breath" stuff doesn't really tell anyone anything useful. For starters, how much faith do you really want to put in what people say when they're so sick they're about to die? Hypoxia significantly affects mental capacities: [this video] For all you know, these people don't actually realize that they're sick at all.
There was a video I watched years ago where someone was on an airplane and basically tested how they'd react with a lack of oxygen. It was pretty crazy. He knew he needed oxygen, but didn't feel like he needed to do anything about it. I think it was this one: [this video]
Person tests reaction to lack of oxygen on a plane.
Time of useful consciousness would be another interesting number to add. Here's a table of average times published by the FAA for a gradual ascent: - 18,000 ft; 5,500 m: 20-30 min - 22,000 ft; 6,700 m: 10 min - 25,000 ft; 7,600 m: 3-5 min - 28,000 ft; 8,550 m: 2.5-3 min - 30,000 ft; 9,150 m: 1-2 min - 35,000 ft; 10,650 m: 30-60 sec - 40,000 ft; 12,200 m: 15-20 sec - 43,000 ft; 13,100 m: 9-12 sec - 50,000 ft; 15,250 m: 8-10 sec Here's a demonstration of the effects of hypoxia and time of useful consciousness done in a hyperbaric chamber by SmarterEveryDay: [this video] [1]: [link]
Hyperbaric chamber demo of hypoxia and useful consciousness time.
Video list and Hacker News comment labels from HackerTube (prompted by @karpathy), released under ODC-By 1.0, built on the open-index/hacker-news archive. Hacker News data is provided by Y Combinator; comments remain the work of their authors. Video titles, channel names and thumbnails belong to their creators and are shown via YouTube. HackerTube Watch is an unofficial edition. Data export of 2026-10-31.
Plays via YouTube's privacy-enhanced embed
13 Hacker News comments
From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.
Citations, criticism and jokes
Read more
Read more