Adam Savage: satan

By Phil Plait | September 9, 2008 2:30 pm

I’ve been looking for this video for months! My close personal friend™ Adam Savage showed this to me a while back, and I’ve been dying to post it here, but didn’t see it on YouTube until yesterday (linked from Wired). I laughed myself silly when I first saw it, and I’ll readily admit I cracked up watching it again just now. Man, it’s funny.

He warns people not to do this at home, but sulfur hexafluoride is evidently really expensive, so it’s not that big a worry I think. But wow, I’d love to try that. I’d probably scare the crap outta my dogs.

CATEGORIZED UNDER: Cool stuff, Science

Comments (80)

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  1. The Sky is Falling! « theBIOT | February 26, 2009
  1. Grendels Dad


    If I had a tank of that and an empty wrapping paper tube my dog would never speak to me again.

    What, your dogs don’t speak to you? Well, never fear, mine hardly ever tells me to tape bacon to cats.

  2. Greg

    The warning is sound. There was a rumor at my school that a professor inhaled xenon or some other ultra-heavy inert gas to try to demonstrate this, and he nearly suffocated. He couldn’t expel it all from his lungs with his own strength and the TAs had to invert him so the gas would roll out of his lungs.

  3. Alex Besogonov

    Sulfur hexafluoride is _cheap_, it’s about $30 for 1kg, though it’s hard to find a supplier which can deliver it in quantities less than 50-100kg.

    A year ago I bought some sulfur hexafluoride to replicate this experiment: – it was really cool.

  4. Colin J
  5. LOL! We just watched that episode at home, and my daughter wanted to do that. I’ll just have to tell her I can’t afford it!

  6. Brian T.

    Question: Since it has sulfur in it, does the gas make your breath stink afterwards? I really want to try this some time!

  7. Brian T.

    By the way, Adam kind of sounds like Penn Jillette towards the end there. Imagine what Penn himself would sound if he got a hold of that stuff.

  8. andy

    Brian T.: I was thinking the same thing…

  9. Alex Besogonov

    Brian T.:

    No, sulfur hexafluoride is completely odorless and tasteless (no wonder, it’s almost completely inert).

    You’re thinking about H2S – hydrogen sulfide, which SMELLS.

  10. elgarak

    Damn, he has balls: He doesn’t use a regulator on his gas cylinders!

    (And yes, we did this in our lab once when we got a bit of SF6 on loan for one quick experiment. SF6 is cool to play with — much cooler than Helium. Or maybe that’s just because it’s more expensive).

  11. Bigfoot

    So, the devil sounds like that because dense gas sinks into Hades? I smell a thesis!

  12. Ryan

    From what I’ve read on online (ymmv), Sulfur hexaflouride is fairly harmless, so long as it’s inhaled in small doses. It’s inert, so you won’t get chemical burns or blood poisoning. But, as Greg mentioned above it can pool in your lungs, so doing this more than once can become really dangerous really fast. A few deep breaths is usually enough to mix most of it out and get enough oxygen in the lungs again. I’ve no clue what the stuff costs.

  13. elgarak

    About the dangers: Both Helium and SF6 are about the same danger. The “turning people upside down to get it out” is not necessary, though, healthy lungs provided.

    They both have the same danger: They displace the oxygen. I got fairly light-headed once when doing Helium twice within 10 min or so. It’s an interesting feeling to nearly pass out, but not something I really want to do!

  14. Oh man, that is so great I am speechless from laughter…
    I just googled sulfur hexafluoride — $10.00/lb (!!!) Helium, otoh, is about $0.15/lb

  15. OH MY GOD! He sounds like Penn Gillette!

  16. H2S Would also kill you – it’s sour gas.

  17. Rob Menke

    There’s another impressive demonstration using SF6. It’s five times more dense than air, which means you can float tinfoil boats in it:

  18. Did he show that at TAM6? That is very funny. And he does sound like Penn, which is kinda scary. lol

  19. ctcoker

    SF6 is pretty much harmless. It’s almost entirely inert (I’ll explain in a bit), and as has been said, the “invert to let the gas out” is pure myth. Your lungs are in fact able to push air out through water (from; the only reason you can’t breathe underwater is your lungs can’t extract the dissolved oxygen. And SF6 isn’t really all that expensive; remember, a pound of the stuff is still what, something like a cubic foot at STP? The expensive part is the tank, which the supply store must sell to you with the gas. That on its own is several hundred dollars even for a small one.

    Now, SF6 isn’t completely inert. Around strong electrical discharges (especially coronal discharge), it’ll reorganize into disulfur decafluoride (S2F10), which is something like phosgene in toxicity. But, since I doubt most people are going to be inhaling it near an active Tesla coil, I think this danger is rather small.

  20. It really isn’t that dangerous. If you pass out, you stop breathing through the balloon and start breathing normally. Worst case scenario, someone may have to do mouth-to-mouth.

  21. oku

    Dave, the price per volume though is almost comparable to helium. He has an atomic weight of 4, SF3 146, that a factor of 36.5.

    It’s a good thing when it’s expensive. SF6 is the most evil greenhouse gas, with a pontential of 22,000 times that of CO2. Releasing 100g of it is like driving a few thousand miles with an average SUV.

  22. «bønez_brigade»

    I lulzed. Y’know, if James Earl Jones ever croaks, this provides a CGI-free way of duplicating the sounds of Vader and Thulsa Doom (if ever they’re revived, that is).

    The host of the ArcAttack! show would fall into that category, though I think he’s all natural.

  23. id like to hear billy mays after inhaling some of that stuff.

  24. Grand Lunar

    That is TOO funny!

    I wonder how Jamie would sound if he used the sular hexafluoride gas.

  25. Chip

    Wait a minute, what if James Earl Jones inhaled sulfur hexafluoride before announcing?!? He would probably be commandeered by the military and used for psychological warfare.

  26. timbo

    I’m pretty sure his explanation is wrong because sound travels faster in a MORE dense medium. That’s why you hear things a lot sooner in water or on a railroad track, right?

  27. JimB

    Ever thought about making an open thread on Wednesday evenings dedicated to the Mythbusters. I would have been on last week.

    I don’t think I’ve laughed as long and as hard as I did last Wednesday with that episode of Mythbusters. Fainting goats, Adam inhaling various gasses and one incredibly cool explosion. I was in heaven. (don’t worry anybody, it was athiest heaven…).

  28. JimB:

    Atheist Heaven… where would that be? The middle of nowhere? :)

  29. Helioprogenus

    It’s also 22,000 times more efficient as a greenhouse gas then CO2. So that liter or so that Adam used to demonstrate the voice drop could have been better spent having a few BBQ’s, or driving a hummer 15 miles (the latter’s a back of the envelope calculation that is probably wrong–thus, feel free to correct the figure). Still, in the interest of science, and the awesomeness of sounding like an underworld minion, it’s totally worth the carbon footprint.

  30. Phil, something is wrong with the Abe Vs. LHC post. There’s no way to post comments.

  31. wb4

    I’ve never understood the standard explanation for why your voice sounds higher when you breathe in helium. It’s not the speed of the sound waves that determines their pitch. It’s their frequency. So what if the sound travels faster in helium? It slows down to its regular speed when it transitions out of the helium into the normal air, before it reaches the listener’s ears. More to the point, the frequency at which they arrive should be the same regardless of how fast they traveled from their source to get there.

    I think the reason your voice is higher is that your vocal cords are surrounded by a gas that, because it’s less dense, applies less of a damping force to your vocal cords as they vibrate. This allows them to vibrate faster than they do in normal air. Hence, the higher pitch.

  32. Robert Krendik


  33. Robert Krendik

    You know what would be awsome, if you went on the Mythbusters show!

  34. JGM

    Well, wb4, I’m glad somebody knows how sound waves propagate. The speed of sound depends on the density of the media it’s traveling through. The less dense, the slower the speed, and the more dense, the faster sound travels! Look up the speed of sound in air versus water and you will see sound travels much fast in water.

    As wd4 points out, the vocal chords can vibrate much faster in the less dense helium, producing a higher pitch (higher frequency sound waves) and they vibrate slower in the higher density sulfur hexafluoride.

    I’m shocked, Phil, you ought to know better!

  35. PG

    I problem is, since SF6 is heavier than air, it hangs around in your lungs. You have to stand on your head for a while to get it out!

    I’ve seen this demo live at a class at Harvard U. It was awesome!

  36. PG

    SF6 is electrochemically identical to CO2, so it’s just a harmless unless it happens to be keeping O2 from getting to where it needs to be in your lungs.

  37. OMG! He’s a Goa’uld!

    He should have said “Kneel before your god, sholva!”

  38. Close observers will note that inhaling the SF6 was not strictly necessary. The “raspberry” of the gas escaping the balloon was noticeably lower in pitch.

  39. Courtney

    wb4: The real reason that people’s voices change when inhaling various gasses is that the changing speed of sound changes the resonant properties of the vocal tract, because the resonant frequency of a tube is proportional to the speed of sound. See this Wikipedia page (specifically the “Open” section) for more information.

  40. Craig

    Alex Besogonov said: “…You’re thinking about H2S – hydrogen sulfide, which SMELLS.”

    So true…it’s the rotten egg smell you get from a bottle of propane, for example. It’s put in there on purpose to help detect leaks, but in very, very minute quantities. I live in an area of Canada where a LOT of sour gas wells are being drilled and developed every day, and the H2S occurs naturally. The trouble is, in the concentration you find around a well, you would never smell it — this is because before your brain has time to say “Holy rotten eggs, Batman!” you are DEAD!

    Don’t mess with H2S EVER! (Uses best Adam Savage impersonation)

  41. I think Dr. Karl Kruszelnicki mentioned once that he got into serious difficulties doing helium on tv once – some of the crew noticed and started him breathing again. Adam’s video though is hilarious.

  42. JME

    The deep voice thing works with Nitrous Oxide too. Available at your local tobacco supply store…

  43. Propane doesn’t have H2S in it. It has mercaptans. Those are sulfur compounds too, but they’re organic, and are the active ingredient in skunk and cat spray.

    I suspect those tanks just had air in them, and they altered his voice electronically. Remember, it’s TV, so they do whatever’s cheapest (and safest), and the effect is the same, or close enough for TV audiences, and maybe “better” than the real thing.

  44. Mark Hansen

    Nathan, helium works and is safe enough. I have tried it myself, usually at parties, and am still breathing well enough. Having never tried sulfur hexaflouride, I can’t vouch for its safety or effects, but I’d say the demo was real. Did you just feel like posting because gas was mentioned?

  45. !AstralProjectile

    OKU says:
    “Dave, the price per volume though is almost comparable to helium. He has an atomic weight of 4, SF3 146, that a factor of 36.5.”

    I think you got the numerator and denominator mixed up !

  46. Blaidd Drwg

    Worst case scenario, someone may have to do mouth-to-mouth.

    Might be worthwhile, if you could specify Kari Byron to be the one giving you mouth-to-mouth…I’d volunteer in a heartbest.

  47. When I read, “sulfur hexafluoride is evidently really expensive”, I thought you said “explosive”.

    Then he was breathing it in and I was at the edge of my seat…

    *I haven’t had my morning coffee yet*

  48. @Nathan: Sometimes the cheapest option is doing it for real. The mythbusters are AFAIK not afraid of putting themselves in mild danger in a controlled environment. And they probably have good insurance.

  49. madge

    Johnny was a chemist
    Johnny is no more
    Coz what he thought was H2O
    Was H2SO4!

  50. @Phil: Satan is a proper noun, at least the way you’re using it here. Ur doin it rong; please re-case the header. 😉

  51. Todd W.


    Here’s an easy way for you to test whether or not the Mythbusters were lying about that: find yourself some helium and some sodium hexafluoride, and try what Adam did. Inhale a small amount of one, speak, clear your lungs, and repeat with the other gas.

    If you don’t want to go out and buy it, you might want to visit a local university chemistry department and see if they can help you out.

  52. Tom

    Does anyone know what the mathematical relationship is between the density of a gas and the resulting drop in voice frequency? (If I breathe in a gas that has a density of x, my voice pitch will rise/drop by y)

  53. Ted S.

    If Penn Jillette breathes helium, will he sound like Adam?

  54. Calli Arcale

    My freshman chemistry prof tried this with argon. He ended up passing out, fell over in front of a class full of elementary students, and immediately came too again since he reflexively inhaled some normal air at that point (and was horizontal, allowing the argon to flow out more easily). I suspect it depends on how *enthusiastically* you inhale it, and whether or not you hyperventilate first. (Adam hyperventilated briefly, which in addition to getting rid of the helium and returning his voice to normal, would’ve gotten extra oxygen into his blood.) My prof was kind of a hyper guy, and I could see him doing this badly, especially since he didn’t try it out ahead of time.

    He had a tendency to think up cool demonstrations and then do them in front of the class before trying them out in a lab. He narrowly avoided injuring anybody when he tried out his cunning plan for allowing us to see liquid carbon dioxide. It did work. He packed a disposable eyedropper (single-piece blow-molded construction) with dry ice, clamped the tip shut with a pair of pliers, and then held it over the screen of an overhead projector. The projector cast the silhouette on the wall and also heated it up, allowing us to clearly see bubbling liquid for a few seconds before the pressure overcame our professor’s grip on the pliers and sent the eyedropper rocketing around the room (fortunately missing everybody, since he had not taken any particular care to avoid aiming it at people).

    Science can be exciting sometimes. 😉

  55. Philip

    A word of caution along the fun with inert gases! They can kill and they have killed.

    One deep breath is more than enough for your voice to change, and note how long Adam actually has a high pitched voice while exhaling(speaking).

    And note that he takes several deep breaths of fresh air before turning to the sulfur hexafluoride. And then again only takes a breath.

    Please do not take this lightly. I have witnessed a friend taking two deep breathes of helium turning blue quicker than you can say oops. And one can also get hurt when dropping to the floor due to becoming unconcious quickly.

    Now getting rid of the inert gasses out of the lung has not a lot to do with their densities and is much more difficult than inhaling. The position while exhaling makes no difference!

    Gasses quickly diffuse into each other, different to liquids.
    When exhaling, you still have some air left in the lung.
    Now you breath in a pure gas like helium. It quickly diffuses into the left over oxygen poor air in your lung.
    Exhaling again, some air helium mixture remains in your lung diffusing into the next breath you take, consequently not providing enough oxygen.

    Only the second, third or more air breath after inhaling helium or sulfur hexafluoride
    will provide your lungs with an adequate percentage of O2 to sustain conciousness.

    There are also some partial gas pressure effects and the chemical workings of the breathing reflex of interest when considering taking a sip of helium.

    I’d suggest that, after having fun, some applied science post on the workings of the lung under inert gases should be in order?!

  56. @Todd W: I have no doubt the results would be as portrayed. I just wonder if there actually were any results, in this particular case. TV isn’t science; they’re allowed — even, at times, obliged — to fudge for effect, so the doubt is legitimate.

  57. Mark Hansen

    Nathan didn’t independently verify it and apparently isn’t going to do his own independent research so he feels that leaves legitimate doubt. Come on Nathan, you can’t have it both ways, either do the research or don’t make wild speculative guesses.

  58. Torbjörn Larsson, OM

    Now, SF6 isn’t completely inert. Around strong electrical discharges (especially coronal discharge), it’ll reorganize into disulfur decafluoride (S2F10), which is something like phosgene in toxicity.

    The fluorine decomposition means that SF6 is used as an dry (i.e. plasma assisted) etchant in semiconductor industry. As HF etches glass, fluorine compounds can etch oxides (for example, silicon dioxide on silicon wafers).

  59. themadlolscientist

    I don’t know which is scarier, Adam sounding like Satan or sounding like one of the South Park guys. Or more appropriate. :-)

  60. Todd W.


    Yes, the Mythbusters fudge things sometimes. But, they are usually pretty up front about their fudging. They explain about what they are doing and how they build things. It’s typically where there is some extreme danger in telling what they’re doing that they hide the details (e.g., mixing up highly combustible fertilizer or making gunpowder).

    While your hyperskepticism may lead you to doubt this clip, there is no realistic reason for them to have used any audio manipulation to change Adam’s voice, other than the use of the gas itself.

  61. @Mark Hansen: Try to follow this: you can suck SF6 until you’re blue in the face (literally) and it won’t tell you anything about what they actually did in production of that video. Hence it’s not physically possible for me, or you, to “do the research”.

    @Todd W: The potential danger is a realistic reason to use audio manipulation instead. It doesn’t mean they necessarily faked it, or that they didn’t. They’re as apparently up-front as they feel their credibility requires; we have no independent measure of how up-front they really are. Remember, it’s entertainment, not science. If it was faked, that doesn’t mean they’re “lying”. It’s just TV, so anything goes. It doesn’t really matter, but it’s equally as legitimate to doubt as to believe.

  62. Why assume they faked it? That was the last thing I thought they’d do. This is the sort of thing that the Mythbusters could do as easily or easier than faking. If it didn’t work it wouldn’t get shown. The Mythbusters don’t have the same motivation or agenda to “fake” something as simple as sucking on a gas as say the Beijing Olympic Committee did when they “faked” some of the opening ceremony. And, it absurd to think that to doubt and to believe, or vice versa, are equally legit. Not about the same thing they can’t – the preponderance of evidence will most of the time go one way or the other.

  63. Davidlpf

    Also Nathan to you are using faulty logic by reasoning since some people lie all people lie.

  64. andyo

    I was also gonna comment on the speed of sound in less dense media being the opposite as what Adam said, and that it’s not really the reason anyway that helium does what it does.

    I was gonna say that I’d thought (I read it somewhere long ago) exactly what wb4 and others mentioned above, that it’s because on a less dense medium vocal cords vibrate at a higher rate, but then Courtney had this to say:

    wb4: The real reason that people’s voices change when inhaling various gasses is that the changing speed of sound changes the resonant properties of the vocal tract, because the resonant frequency of a tube is proportional to the speed of sound. See this Wikipedia page (specifically the “Open” section) for more information.

    I didn’t quite get that wiki link. I don’t read numbers that well. Anyone care to follow up? Thanks.

  65. Mark Hansen

    @ Nathan: Try following this. Research is as simple as asking the production crew so definitely physically possible. No need for blue faces. Perhaps a red one?

  66. Todd W.

    Another note, if it was deemed too dangerous, their insurance company would say they couldn’t do it. And, when that happens, they typically show it. For an example, see the movie myths episode where they looked at the falling through awnings bit from Indiana Jones.

    The experiment can be done safely and without harm to the person performing it. That, alone, nixes your safety concern as a reasonable cause for faking it.

  67. Todd W.


    One more note. Just about everything that the Mythbusters do involves some measure of danger, even if they fake something. Just building some of the rigs involves the risk of serious injury. Having worked rather extensively around power tools myself, I can vouch for the respect they require.

    By contrast, the clip where Adam alters his voice using helium and sodium hexafluoride shows an action which, when done correctly, has little to no risk of serious or permanent injury. Even if Adam had inhaled too much gas and passed out, as others have noted already, the body does quite well at expelling “bad air”. Even if he did pass out and did not come around on his own, I’m reasonably certain that they have a medical crew (or at least people in the shop, like Jaime, who are CPR certified) that could assist him in clearing his lungs, with no lasting damage.

    So, the short of all this is, Adam would be far more likely to sustain serious injuries working with the tools in the shop than he would to suffer harm from the gases. Ergo, no reasonable risk of injury and no reason to fake it.

    Perhaps you have some other compelling, rational reason that the clip could have been faked. However, the more I read your posts, the more you sound overly skeptical. In other words, you seem to doubt simply for the sake of doubting, rather than having truly logical reasons for those doubts.

  68. @Todd W: People are often hurt when they fall, a real possibility (as has been expained by other posters) . But safety is only one plausible reason. Another is deadline pressure; they might have wanted to show the effect, but couldn’t get the SF6 in time to shoot it for that episode. Or, it might just have been quicker an cheaper to fake it; every studio already has all the equipment needed, but you have to order SF6 and get it delivered. The point is, I’m not “assuming” they faked it. I don’t know, and neither do you, and neither does Mark. But I wonder.

    I understand that in some circles it’s considered rude to doubt whatever has just been made up, for the sake of convenience and comity. I prefer objective reasons, and let comity look after itself like an adult.

    @Mark: I don’t care enough to ask the crew; I’m satisfied with not knowing. The evidence suggests you feel exactly the same, although no doubt you experience the “not knowing” a little differently. But it’s dishonest to talk now about asking the crew, when you were claiming earlier that I could resolve the matter by sucking SF6. Face red?

  69. Mark Hansen

    I didn’t suggest inhaling SF6; you and Todd W. did. Better brush up on those reading skills. Saves embarrassing call-outs later. And if you don’t care enough (i.e. are too damned lazy) to ask the crew, then why even bother suggesting they faked it? Beyond a pathological desire to troll, that is.

  70. Todd W.


    The point is, I’m not “assuming” they faked it.

    Hmm. If you aren’t assuming that they faked it, then I must have read your earlier comment wrong:

    I suspect those tanks just had air in them, and they altered his voice electronically.

    Maybe it’s just me, but that sounds like you are suspecting them of faking it. I don’t buy the deadline pressures. If that were the case, then the entire myth involving the SF6 would have been faked. While possible, it is not very plausible. Again, cheaper and faster, while a possible explanation, also is not plausible. Yes, producers want to find ways to keep costs down and production moving, but very rarely at the cost of quality. They buy the things that they need to do the experiments: they buy cars, tanks of compressed air and so on. I also figure that they pay some fees to have fire marshalls or other consultants help out with some of their more dangerous experiments. Compared to these, the cost of the SF6 bit is negligible.

    I’m curious about your reasons for criticizing just about every post on here, either doubting some detail or claim, or simply voicing some critique of the grammar. Are you posting that way because you really doubt? Is it just to be the voice of doubt for doubt’s sake? Do you have something against Phil (and by extension the readers that post in support of him)? Or are you simply taking the role of troll, posting simply to get a rise out of people? Perhaps you are just trying to help people hone their debating skills, though the occasional ad hominem attacks you make don’t seem to support that rationale.

    There is nothing wrong with doubt, as long as there is a rational reason for it. One must weigh the likelihood of the various possible outcomes or reasons. As far as inhaling SF6: possibility of passing out and falling over? Yes. Likely? Not if only a small amount is inhaled. Possibility of injury from falling? Yes. Serious, life-threatening or permanent? Not likely. As evidence of this, I offer a personal experience. While in college, I stood up very quickly in my dorm room and got a head rush, passed out, and woke up a couple seconds later on the carpet-covered concrete floor. By the slight headache, I had apparently bumped my head. I did not, however, suffer any broken bones, concussion, or any other serious injury. I admit, it’s just one person’s account, but it still stands as an example of what can happen.

    In the end, though, it can be assumed that just about anything one sees on TV can be faked. However, just because something can be faked, doesn’t mean it was. Unless you have specific reasons and credible evidence to support your statement that you suspect that they faked it, there is little reason to make the claim, unless, of course, you just want to draw others into debate.

    Sorry for the long-winded post, everyone, but I felt the need to address Nathan’s comments.

  71. @Craig,
    I lived in Edmonton, and then Fox Creek, halfway between Edmonton & Grande Prairie. I had friends working in the oilfield who had to train on how to deal with H2S – the program was H2S Aware, I think. A few times, people have gone into the tanks and have been overcome by Sour Gas. Sadly, several didn’t make it. It overcomes them so fast, they literally do not have time to react.

  72. Thomas Siefert

    Well so much for the secret behind the voice of Tom Waits….

  73. Mark Hansen

    Nathan, no response? I shall take it that your silence is an admission of getting it wrong in saying that I suggested you use SF6. Calling me dishonest is really rich. Little tip; learn to read what others have written, not what you think they wrote.

  74. Todd W.

    @Mark Hansen

    From what I’ve seen of Nathan’s posts in this and other threads, he will not admit that he was wrong about anything, in the same way that he will critique just about anything without providing sound reasoning for the critique and the sources to back up the critique.

  75. Mark Hansen

    Agreed. Perhaps the best course of action is inaction where Nathan’s posting is concerned.

  76. Adam’s warning is indeed sound. I remember reading about a case a year or two ago where a couple of teens crawled inside a large helium (weather?) balloon for a laugh, and suffocated.

  77. Ryan

    There is nothing particularly dangerous about the use of inert gases such as sodium hexafluoride or helium if you are in a well ventilated area. If you overdo it, you may pass out, but will probably resume breathing when you hit the floor. The reason this isn’t terribly deadly is because of the REASON you pass out. When you breathe CO, it displaces O2 on hemoglobin. Inert gases dilute CO2, the problem of course is that CO2 levels are how you determine you need to breathe: air hunger (incidentally, this is why hyperventilating before diving is so dangerous. It won’t increase the amount of O2 carried by hemoglobin, but it will deplete CO2 so y0u may run out of O2 before you FEEL like you need to take a breath).

    Regarding the greenhouse effect: SF6 is very dense and doesn’t mix all that well with air which means it is found close to ground level which significantly limits its effectiveness as a greenhouse gas.

  78. diman

    who knows anything email Adam Savage?


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