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The anesthetic effect of air at atmospheric pressure

pubmed.ncbi.nlm.nih.gov

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Re: The anesthetic effect of air at atmospheric pressure

#201

Post by extraduder_ire »

scirpaceus wrote: post #156
extraduder_ire wrote: post #144

Earlier quoted context omitted.

>Except for helium, no other gas exists which does not have some form narcotic effect at higher pressures. According to something mentioned in passing in a Scott Manley (amateur space youtuber) video about deep-sea diving: at high enough pressures you'll get similar effects from helium. It's thought that you can avoid this by subbing out the helium for hydrogen, but nobody so far has been insane enough to try. I assu…

> It's thought that you can avoid this by subbing out the helium for hydrogen, but nobody so far has been insane enough to try. It's reportedly been done very recently using a rebreather ( https://gue.com/blog/n1-the-inside-story-of-the-first-ever-h... ). Prior to that, in 1992, there was the French COMEX-sponsored HYDRA 10 experiment that saw Théo Mavrostomos dry-dive in a chamber to 701 meters (71.1 bars) - the wor…

Reading that first article freaked the hell out of me, thanks.

Glad there's some people out there nuts enough to push the limits of this stuff. No idea why those people in new zealand don't use pressure suits to dive in that hole though.

Re: The anesthetic effect of air at atmospheric pressure

#202

Post by gojomo »

nradov wrote: post #193
gojomo wrote: post #187

Earlier quoted context omitted.

The delivery mechanisms for a nitrogen-free air – be they personal respiration devices or sealed environments – could be onerously regulated, or effectively banned for certain places/purposes. It can be hard to confine helium, and its presence can make some electronics malfunction: https://www.ifixit.com/News/11986/iphones-are-allergic-to-he... Occasional helium shortages, and the characterization of terrestrial heli…

Where are you coming up with that nonsense? You can get helium from any gas supplier, confine it indefinitely in tanks, and breathe it using any pressure regulator. No one cares.

A number of municipalities have already banned all helium balloons simply due to litter concerns. Major suppliers rationed helium sales as recently as 2022, after the Ukraine war limited supplies from Russia. Helium has often been the subject of proposed legislation for increased government management of prices or supplies, or special discounts for favored uses.

Now imagine a major new use – displacing nitrogen completely, for cognitive enhancement, for an entire work day – arrives. Some can tolerate traditional pressure regulators, but others dislike their bulk/discomfort – so novel delivery strategies, with more leak/loss (like full-room environments), proliferate.

Prices would be driven up for traditional (& government-favored) medical/industrial/research users. Helium leak detectors in industrial settings would face more false-alarms. Exhalation/outgassing would sometimes cause electronic malfunctions in neighboring offices/apartments. And even if almost everyone gets it right, someone somewhere will err in their processes, injuuring or even killing people.

New supply regulations against this novel, & politically disfavored use, would then be a risk – even if the net performance gains still significant.

As informative precedents, in the US, consumer access to pseudoephedrine, flavored cigarettes, & plastic straws has been noticeably restricted in the last decade, on flimsier rationales. It's become more difficult to acquire racetams & other nootropics in just the last few years. California is in the process of banning all gas appliances, despite a long tradition of cheap/easy access via household utility hookups.

So, while I'd hope you're right that no new restrictions on helium-purchasing would arrive, your certainty seems naive, in a childlike & history-oblivious way, to how reactionary supply-control regulations often develop.

Re: The anesthetic effect of air at atmospheric pressure

#203

Post by dTal »

genewitch wrote: post #88
dTal wrote: post #85

Earlier quoted context omitted.

All you need is zeolite crystals and a compressor. Zeolite fixes nitrogen under pressure, so you can use it to separate nitrogen from oxygen. This is how those "oxygen concentrators" work. I'm sure you get can hold of a relatively-cheap chinese one, they don't have dangerous parts or controlled substances. But it wouldn't be that hard to build one from scratch either. https://www.aliexpress.com/w/wholesale-oxygen-con…

> Sorry, your search "oxygen concentrator" did not match any products. Please try again. i thought it might be because of the /w/wholesale path, so i went to aliexpress (i have an account) and searched on the main page, and it gave the same result. Curiously, "oxygen concentrat" as the search term brings up alleged devices. This dovetails with my very short comment that such devices are hard to find without prescript…

Wow. Indeed my country was not set to USA. It seems that they do filter the results for USA customers, and researching further suggests that the FDA's position is that they not be used without a prescription. But is it illegal to sell one? Is it illegal to even make one? The situation seems murky. And silly.

Re: The anesthetic effect of air at atmospheric pressure

#204

Post by reportgunner »

haldujai wrote: post #189
reportgunner wrote: post #176

Earlier quoted context omitted.

> Lately I've been finding Bourbon to be enjoyable. Woodford Reserve and Bulleit are well-priced and good introductions in my opinion. Also try Buffalo Trace, it's one of my three favorite including the two you mentioned.

Thanks! It's on my list, I haven't gotten around to it yet. Would you suggest the regular Buffalo Trace or one of their (many) variations?

I have only tried the regular one but I liked it a lot.

Re: The anesthetic effect of air at atmospheric pressure

#205

Post by slau »

todd8 wrote: post #171
slau wrote: post #5

Just completed my deep (40m/120ft) diver certification. A significant amount of the course was focused on nitrogen narcosis, and how to handle/detect it. Apparently, some divers will start feeling the narcotic effect between 20-30m. Beyond 30m, a significant amount of divers can feel the effects. Beyond 40m is the realm of tech diving, with trimix (helium/nitrogen/oxygen) or even heliox (helium/oxygen). I know nothin…

While I am certified for Nitrox diving, I'm not sure I would actually use it very much. After over 100 open water dives and many dive classes (I was one class away from being a certified instructor back in the 1970s) I realized that I didn't want to do extreme diving. Night dives in the Caribbean are exciting enough. Wreck diving, ice diving, cave diving, commercial diving, hard hat diving all seem too dangerous. Div…

Nitrox is the single most issued specialisation. It’s most useful for repeat dives and on reasonably shallow dives. The most benefit you’ll get is in the 20-30m range.

As I mostly dive cold waters, I use a max PO2 of 1.4, instead of the 1.6 that some people use. This means that for deep dives (30-40m), I typically end up with EAN28 instead of the more common EAN32.

Nitrox is definitely not “extreme diving”, though. It’s just a way to increase your bottom time and reduce your surface interval. Just remember to keep an eye on your CNS%—there’s a limit to how much oxygen your body can safely handle.

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