> So what else could it be? Well, at the heart of every electronic device is a clock. Traditionally, these are quartz oscillators, crystals that vibrate at a specific predictable frequency—generally 32 kHz.
Watch crystals run at 32[.768] kHz because you can divide with a binary counter by 2^16 and get 1 pps to drive the Lavet stepper driving the seconds hand.
Watch crystals are also commonly used by MCUs for their RTC (real time, very low power clock), but never used to produce the main clock of a SoC or something like that. Mostly because that'd need an insanely high multiplication through a PLL (higher frequency multiplication ~ higher phase noise). Base clock crystals are typically 20-50 MHz.
Traditional crystals come in what's referred to as a "hermetic metal can", i.e. a metal box soldered closed with leads going through glass seals. I don't know if that's good enough for Helium.
The sealing is mostly because of humidity. I wouldn't expect quartz crytals to be overly sensitive to some gas, since they're basically tuning forks; the crystal physically vibrates in a resonance mode caused by and inducing an electric current across the crystal.
Hermetically sealed by definition is airtight, i.e. "excludes the passage of air, oxygen, or other gases". [1] With that said, the diffusion rate depends on both the properties of both the seal and the gas.
I agree it is unlikely to be the RTC clock at issue unless it runs a watchdog of done form. But given that they are using MEMS for the 32kHz clock it seems likely they are using it for other clocks too.
Helium is very good at getting through the tiniest cracks due to its small atomic diameter. One uses it to find leaks in devices with ultra-high vacuum seals (e.g. in low-temperature physics) by attaching a pump with a simple mass spectrometer sensitive to Helium to the device under test and then using a small helium gun to test different parts of the device from the outside. When spraying it at the leak some of it is pushed inside by the pressure difference and can be detected by the pump spectrometer.
Hydrogen would be even better of course but it is rather dangerous when mixed with air.
Hydrogen would not be better. A helium atom is considerably smaller than a hydrogen molecule. Even if you could use atomic hydrogen, the helium atom's radius is significantly smaller due to the higher central charge that is only partially screened by the "other" electron.
Hydrogen binds with other hydrogen atoms to create H2 which is the only form of elemental hydrogen you’ll see outside of a lab helium is unique in that its singular atom is its own elemental molecule.
Hydrogen would be better. Size isn't the most important factor. Gasses with low molecular mass have higher particle velocities. The velocity affects mixing, passage through holes (including filters), and the speed of sound. Hydrogen is about 2 AMU, 1 for each atom, while helium is about 4 AMU.
You can find the formulas in a typical college chemistry textbook.
It gets worse than that when your cryo equipment has a “cold” helium leak. Ie, something leaking on the dilution fridge only at helium temperatures (4.2K) and lower, but no trace of a leak at room temp.
Repeated bouts of guessing where the leak might be and trying to plug it (usually by welding or re-machining some part), cooling down, checking if it worked, warming up, ripping some more of your hair out, repeat.
Yeah I had that as well, in that case it was best to replace all the Indium seals right away as like you said it takes 24 hours to do a full cooldown/warmup cycle anyway, so spending a day to make new seals is often faster. That's a part of low-temperature physics I definitely don't miss!
I worked on a system where I needed to reach and maintain pressures of 10^-3 tort, and that was hard enough. I can’t imagine having to deal with helium sensitivity.
Electronic parts also get helium exposure on the launch pad in a rocket. I know for example there can be helium sensitivity issues on gyros for CubeSats.
Hydrogen is soluble in most metals. It will just diffuse right into it, like air flowing through a foam filter.
Added bonus: if the metals in question form chemical bonds with hydrogen, (titanium in particular) it will happily do so, even if it's deep inside the metal. The metal will turn very brittle very quickly if it's exposed to molecular hydrogen.
Even a single hydrogen atom is bigger than a single Helium atom. The charge of the helium nucleus is higher and thus "pulls" the two electrons further inward than Hydrogen's single proton pulls its single electron.
Hydrogen exists as H2 in its elemental form you’ll you’ll need to ionize it to separate it and keep it in an ionized or other way isolated form to prevent it from binding to other hydrogen atoms.
Maybe I'm just a fanboy, but I found one of the most impressive parts of the story, aside from actually tracking down the root cause, was that the iPhone User's Guide actually specifically addresses this, along with explaining that it's necessary to give it about a week for the helium to diffuse.
You just know there was a days-long meeting about "the Helium problem", including graphs of how likely different user-personas are to enter a zeppelin, work in a balloon factory, or attend exceedingly well-funded birthday parties.
After debating late nights about whether to pony up for the new better-sealed clock, someone said "Screw it, throw it in the user agreement."
Helium makes up less than 0.0005% of air naturally. I’m guessing that increasing He concentration 1000 times to 0.5%, for example, is enough to cause problems for iPhones, but not enough to trigger the alarm or pose any danger to people.
Breathing helium is completely safe as long as the oxygen concentration is near normal. Hospitals have occasionally even put patients with respiratory disorders on helium/oxygen breathing mixtures because the work of breathing is slightly lower than air.
Considering that Trimix and Heliox used in deep commercial dives can have the majority (Aka >50%) of the breathable “air” be helium, your theory that there’s really any risk of danger to people seems a bit unwarranted to me.
Not enough to directly endanger people, but a hospital is full of electronics that plenty of people need to live, and it sounds like they could potentially share the iPhone’s vulnerability.
Indeed. I had to reread that paragraph. That's a LOT of helium (by volume).
"So, i noticed some of the workers' iwatch's weren't registering the users' heart-rates. At first, I thought it was because they had all died from suffocation from the massive gas leak. But, then I discovered something interesting... it was actually the helium molecules worming their way into the internal clock chip! Amazing day."
Another scary practice is venting natural gas indoors. Most of the time it's fine, but sometimes you get a catastrophic explosion: https://www.youtube.com/watch?v=rjxBtwl8-Tc
(The US Chemical Safety Board has a bunch of interesting videos.)
As long as he helium doesn’t displace the oxygen it is fine. Saturation diving has people living in “heliox” environments where the atmosphere is helium and oxygen.
I discovered that the helium leakage occurred while the new magnet was being ramped. Approximately 120 liters of liquid He were vented over the course of 5 hours. There was a vent in place that was functioning, but there must have been a leak. The MRI room is not on an isolated HVAC loop, so it shares air with most or all of the facility. We do not know how much of the 120 liters ended up going outdoors and how much ended up inside.
Venting 120l of liquid helium (or about 84,000l of gaseous helium) really isn't that much of a health concern
I've seen multiple vents of ~1500l of liquid helium (~1,050,000l of gaseous) in a single day from a couple bad MRI units when I worked at a company that makes them
Only "dangerous" place to be was in the fragmentation path of the burst disc (which was enclosed in the top of the unit (at the time)), or directly in the path of the nearly-liquid (ie extremely cold) helium as it vented
how easy is it? It floats, so it only fills a room from the top down... and if you fall over unconscious, you're automatically moving to a part of the room with more oxygen. it would have to displace all of the air in a room in order to suffocate someone, no?
Right! It's not like an "allergy" to helium is going to be a problem for any user at any time unless, you know, there's a big helium leak, at which point the phone is the least of your problems
Eventually. But I would expect that by the time the effect is noticeable, the concentrations will be too high to support consciousness and will have been for some time.
This is the first time that I remember seeing a story evolve on the internet. What was originally from a post on r/sysadmin 3 weeks ago is now summarized on a Blog article that's at the top of HN. Will it get picked up my mainstream media and be on everyone's news feed by next week? Or tomorrow, now that its picked up momentum? Besides being a really fascinating story, its having an interesting journey as news travels through different outlets and gets condensed and filtered down to more consumable forms.
I remember hearing plenty of whispering that Intel had a major bug disclosure coming up, but for most of that time I feel like the majority of speculation was centered around the Intel ME.
Sadly my immediate reaction to this post on /r/sysadmin was to discount it, or rather attribute it to some external factor that nobody could possibly figure out and entirely unrelated to the MRI. In this case I was quite happy to be proven wrong by the follow up posts and subsequent article.
I'm really curious why something they can generalize to "helium leaking into the quartz oscillator" only affected Apple products. What feat of manufacturing keeps a broad range of OEMs safe on the Android side but so eludes Apple? Worse yet, was some "cost savings" engineered between iphone 5s and 6 that ultimately introduced this issue?
Every time my colleague brought his phone to the control room the Cellular stops working for like a day or two, but my 6s worked just fine anywhere even next to a Dewar that's venting Helium. Now the mystery is solved!
BTW, among us there are others who accidentally brought their phones near or even into the MR bore during maintenance, but none of these devices has done any permanent damage to our phones, except one accelerometer on a cheap Chinese phone, even in a 7T magnet. So I never thought that MRI could be causing the problem.
It's in the iPhone user guide ... maybe not something everyone reads, but it has been known for some time
That said - a 120l leak of liquid helium is both stupidly expensive, and highly damaging to the MRI unit: there's a bath of ~1000-1500l of liquid helium in an MRI to keep the superconducting coils at superconducting temperatures. Losing ~10% of that volume probably means the unit won't work
Few things;
Isn't it a bit odd that a hospital MRI machine room isn't being monitored for these kinds of things? I'm curious, not accusatory.
Also, this could be a potentially catastrophic tool for terrorists. As trivial as it sounds, it's even worse than a traditional frequency jammer because it renders the device unusable instead of just not being able to communicate with the outside world.
Edit: On the other hand, interesting counter-terrorism tool as well. Is there any precedent for the CIA using this sort thing intentionally?
There are almost certainly oxygen sensors in that room. The helium concentration was probably not high enough to displace enough oxygen to trigger them. Though it wouldn't entirely surprise me if they were ignored or disabled.
Liquid helium is rather expensive and would likely draw attention in areas where it's not usually handled. Really doesn't sound like a useful terrorism tool.
One of our multi-practice facilities is having a new MRI installed and apparently something went wrong when testing the new machine.
[...]
I discovered that the helium leakage occurred while the new magnet was being ramped. Approximately 120 liters of liquid He were vented over the course of 5 hours. There was a vent in place that was functioning, but there must have been a leak. The MRI room is not on an isolated HVAC loop, so it shares air with most or all of the facility. We do not know how much of the 120 liters ended up going outdoors and how much ended up inside.
Scaling a "helium attack" against electronics is one of the dumber terrorist plots I've come across. But let's play.
Say I scored a big truckload of helium, 5000 l. (The contents of my tank will expand to 3750 m3 of He gas.) Then I got access to a ventilation duct into the subway. I manage to hook up my tank and start depleting into the subway. Assuming 20 m2 cross-section for a tunnel: if I could do the emptying at once, I could fill 0.187 km of tunnel completely with He; killing all vermin in that section.
But hey my goal is not to suffocate (that would be boring, right?) but to fritz electronics. So I do it slow and steady into a station. Say I want to keep the concentration of He in the station at around 0.1%. (I assume it would take time for operators to detect this. I don't know how sophisticated gas detection is in subways.) Let's assume an airflow of 5 m3/s into that station. I'd need 0.005 m3/s He or 400 m3 per day to keep the level at 0.1%. So for only one day, I'd need to get around 500 l liquid helium into position.
Lol you clearly underestimate some people, but I'm wondering what makes you think that even a frequency jammer in the wrong hands couldn't be potentially catastrophic?
I love HN. I came here to learn more about MEMS RTCs, something I've never heard about previously... But most of the discussion is about the dangers of a helium leak... Which is a good point, especially if that leak is in a hospital.
It's good that he was able to reproduce it (although with a far higher concentration of helium), but the original story showed up a few weeks ago at an EE forum I lurk, and everyone there was skeptical of helium and suspecting EMP instead:
But an electromagnetic pulse would have taken out medical equipment in the facility as well, and they were working fine!
I suspect medical equipment is designed to a higher standard of EMP resistance than most other products, especially equipment designed to sustain life. Phones also have antennae specifically designed to pick up EM fields, while medical equipment like an EEG or ECG is specifically designed to reject them.
Likewise, the devices "reviving" after a week is not unusual if they're just resetting due to power loss. Immediately disconnecting and reconnecting the battery would for sure differentiate between helium (device remains dead even after reset) and EMP (device reboots successfully.)
Any particular reason you're ignoring the fact this only happened to iOS devices? Do the various Android manufacturers incorporate additional shielding to prevent the occasional EMP?
Anybody can provide a reason why SiT1532 wouldn't be hermetically sealed? They are talking about high accuracy, intuitively it would seem that if helium affects it this badly, then it would be susceptible to some atmospheric pressure changes (unless the seal worked against air but not helium).
They do have a strong hermetical seal on them, but the older ones used by Apple are still susceptible to “small gas molecules”.
They must have some seal in place and fortunately our air is Nitrogen, O2, and a little bit of Argon. These can’t get through the seal! Helium is only found in minuscule amounts naturally and apparently this concentration is so low it doesn’t matter.
Helium is frequently used in leak tests since it has a way of working through even the tiniest of leaks. Elemental Hydrogen is of course smaller, but I believe you only find Hydrogen as H2 which is a larger molecule than Helium.
Sealing against Helium is vastly more difficult than sealing against air, as air is made out of molecules of rather large atoms, while Helium gas consists of single small atoms. That is why divers watches often have a "helium escape valve". The watches are sealed against high pressures of water or air. But when worn in pressure chambers where divers live on a mix of high pressure helium and oxygen, the helium gets into the watch. When depressurizing at the end of the pressure chamber time, the helium pressure could blow the watch crystal from the watch if not released by the escape valve. For a similar reason pilot watches have special fastening of the watch crystal, so that underpressure doesn't lift it off.
Those helium escape valves are just for marketing overpriced toys to pretentious wannabes. Most working saturation divers haven't used fragile, expensive mechanical wristwatches for decades now.
>(unless the seal worked against air but not helium).
That is exactly the case. From the article, helium (and to a lesser degree, hydrogen) have very very small molecules and are able to slip past very small imperfections in hermetic seals.
I would be very interested in seeing the the iPhone charges while "anethitized". I severely doubt data would be accessible via standard channels, but as this kills the general clock I am assuming it should prevent any sort of lock protection mechanisms from kicking in indefinitely.
Not sure how you would get it going again and / or how necessary that would be. Perhaps heating it to excite the helium trapped in the oscillator and hoping it bounces out.
Could end up being a pretty easy go to law enforcement trick. Put a phone and a helium balloon in a ziplock bag, pop the balloon, pause the phone, deal with it later
We were wondering if this could be used for iPhone scams. It's a dead-simple way to apparently fatally & totally destroy in a deep & non-diagnosable way a pristine iPhone which will however (probably) reverse itself in a few weeks. It seems like this ought to be exploitable somehow. Something like get a new iPhone, helium it, return it for a refund, and somehow hold onto the phone... Couldn't figure out how it would actually work, though.
how about get a phone, accumulate normal life scratches for 9 months, "helium it" hard, so it lasts a while, then get apple to replace it as defective? iiiiiii dunno... there's a scam in there somewhere, were just not being creative enough!
Depends on the how the charging controller is implemented. There is, at the very least a state machine -- if not an MCU -- managing the charging process. So I think it's highly unlikely to _start_ charging with the clock stopped, and one would hope there are some analog triggers to halt charging (eg. battery over-voltage) if the clock stopped while it was charging.
It was really fun to watch this story develop over the last few weeks on /r/SysAdmin. I found myself checking the OP's profile a few times a week waiting for the smallest update. It's truly mind boggling to me (a software developer with very very limited hard science experience) to think about the ramifications of invisible forces causing these kinds of wild goose chase mysteries.
>the 120 liters ended up going outdoors and how much ended up inside. Helium expands about 750 times when it expands from a liquid to a gas, so that’s a lot of helium (90,000 m3 of gaseous He).
the math seems couple orders off - the 120l would make less than 900m3. The 90000m3 would be on the scale of the total volume of a multi-story hospital building.
My math was fine, but I did get the base numbers wrong. Should have been 120L as mentioned in the article, which equates to 88.577 m^3 at 15C, which is pretty chilly. 20C is more like room temp.
But, I'm not sure your math is quite on the money either.
Wow. This is good to know. As a TriMix SCUBA diver, we should keep our iPhones away from the fill station and away from us when we are venting / testing our mixes :-)
This is strange and I happen to work at a facility that does a lot of open air helium mass spectrometer leak testing.
I'm and Android user so I have no skin the the game. I'll have to talk to some people at work tomorrow. A few guys are iPhone users and work in direct proximity to the helium leak testing stations or use them as well. I know a woman in the office didn't like her iPhone because of numerous problems but I never thought to press her for details.
Would the helium concentration in air actually get high enough to cause problems? As far as I understand leak testing, you don't need a lot of helium for that to work.
> Perhaps there’s a bug in iOS that causes crashes when it gets faulty data from the gyro? But the bug impacted Apple Watches, too—and they run WatchOS.
TL;DR: Apple uses MEMS clocks (while most Androids contain quarzes), which can be affected by Helium molecules even though they are sealed in the attempt to prevent that.
I wonder how aware Apple is of this story. I'm sure engineers browsing here will have seen it, but it'll be interesting to see future iFixit teardowns of devices to see if the MEMS sensor has any different shielding or if they use a different chip entirely.
The article says that Apple's user guide mentions phones not working around helium:
Exposing iPhone to environments having high concentrations of industrial chemicals, including near evaporating liquified gasses such as helium, may damage or impair iPhone functionality.
It's a little hard to take this article seriously when the caption grossly misidentifies a GE BrightSpeed CT scan (x-ray) with a MRI machine. My guess is the magnet was still on (perhaps incorrectly).
Any security hardware using this oscillator would be at risk too. I can see the Mission Impossible plot to use it to attack a security systems and IP cameras if they used those chips.
I'm not sure how far this vulnerability will ever get an attacker because most devices will probably continue to use regular quarts oscillators that aren't sensitive to this like MEMS devices. Apple probably only uses them because they're squeezing every ounce of space and their markups can stand the increased cost of the MEMS vs the quartz/ceramic oscillators.
The microscopic oscillating part in the clock needs a vacuum. Having air around would dampen the vibrations too quickly because the mass is tiny, and the timing would vary with air pressure or humidity.
It sounds like microelectromechanical devices (like the quartz oscillators that keep time in electronics) are so small, and built to such fine tolerances, that helium atoms can literally, physically jam them like sand in a gearbox. That's what the article seems to be saying, anyway.
I guess they're fine under normal conditions because typical atmospheric molecules are actually too big to get inside? I'm not clear why the particular clock that Apple used is susceptible but other ones aren't. I guess they're sealed better.
I've heard plenty of good chemists refer to monatomic gases (and sometimes ions) as molecules, or "molecular", colloquially, and particularly when talking generically in terms where they could be replaced by another gas. That helium is monatomic is both well understood and not especially relevant in many contexts.
He2 is rare enough that the few times I've heard it spoken about, people have usually said "helium dimer" to make it clear that's what they mean. Since that's the rare case, it's the logical one to be explicit about.
> I've heard plenty of good chemists refer to monatomic gases (and sometimes ions) as molecules, or "molecular", colloquially, and particularly when talking generically in terms where they could be replaced by another gas.
I have also seen this, but it has normally been almost exclusively confined to when people talk about the "particles" of gas from a kinetic theory point of view.
A single-atom molecule is a very simple molecule. But it is a molecule: "The smallest part of any substance which possesses the characteristic properties and qualities of that substance, and which can exist alone in a free state."
Molecular helium happens to be identical with atomic helium, where an atom is the smallest unit of an element (not a chemical substance).
Water (H20) is a substance whose smallest unit is a molecule of 1 oxygen + 2 hydrogen atoms. Helium is a substance who's smallest unit is 1 helium atom.
Helium is a 'noble element', check the Periodic Table and tell me how Helium gets to be part of a molecule. Unless a lot has changed since I was at school then you aren't going to get a lot of helium 'molecules'. It just doesn't work like that.
What I don't get is how these helium molecules diffuse into the iPhones so easily, an awful lot of helium must have to leak for that. Normally helium - balloon sized quantities - tends to prefer going skyward rather than hide in an iPhone.
But since that seems to not be the case it would be good to turn up at a concert where everyone is playing with their hand rectangles rather than enjoying the moment, then to release some helium to fix that for them...
> Helium is a 'noble element', check the Periodic Table and tell me how Helium gets to be part of a molecule. Unless a lot has changed since I was at school then you aren't going to get a lot of helium 'molecules'. It just doesn't work like that
Yeah, well maybe they don't tell you all the details and special cases in school...
I am well aware that helium is a noble gas, and generally does not form molecular compounds. Under the right conditions, though, helium can from molecules bound with the van der Waals force: https://en.wikipedia.org/wiki/Helium_compounds
> So what else could it be? Well, at the heart of every electronic device is a clock. Traditionally, these are quartz oscillators, crystals that vibrate at a specific predictable frequency—generally 32 kHz.
Watch crystals run at 32[.768] kHz because you can divide with a binary counter by 2^16 and get 1 pps to drive the Lavet stepper driving the seconds hand.
Watch crystals are also commonly used by MCUs for their RTC (real time, very low power clock), but never used to produce the main clock of a SoC or something like that. Mostly because that'd need an insanely high multiplication through a PLL (higher frequency multiplication ~ higher phase noise). Base clock crystals are typically 20-50 MHz.
Quartz crystals used to be hermetically sealed.
> Quartz crystals used to be hermetically sealed.
Are they sealed against helium though? It can get through a lot of materials that more common gases can't.
Traditional crystals come in what's referred to as a "hermetic metal can", i.e. a metal box soldered closed with leads going through glass seals. I don't know if that's good enough for Helium.
The sealing is mostly because of humidity. I wouldn't expect quartz crytals to be overly sensitive to some gas, since they're basically tuning forks; the crystal physically vibrates in a resonance mode caused by and inducing an electric current across the crystal.
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Hermetically sealed by definition is airtight, i.e. "excludes the passage of air, oxygen, or other gases". [1] With that said, the diffusion rate depends on both the properties of both the seal and the gas.
[1] https://en.wikipedia.org/wiki/Hermetic_seal
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I agree it is unlikely to be the RTC clock at issue unless it runs a watchdog of done form. But given that they are using MEMS for the 32kHz clock it seems likely they are using it for other clocks too.
> I agree it is unlikely to be the RTC clock at issue unless it runs a watchdog of done form.
Fairly standard technique to run the watchdog off the RTC clock, because that might still work if the main clock is wonky.
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Nit-pick - you mean to divide 32.768kHz by 2^15, not 2^16 to get 1 pps.
More nit-picking... according to wikipedia Lavet requires two states for one step, so 2^16 looks good based on this.
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Here is the Post-mortem from the OP on Reddit:
https://www.reddit.com/r/sysadmin/comments/9si6r9/postmortem...
There are some fascinating weird stories in that thread.
It reminds me of the classic "500 mile email" https://www.ibiblio.org/harris/500milemail.html
The excel email attachments one was insane, and great writeup
(https://www.reddit.com/r/sysadmin/comments/9si6r9/postmortem...)
One of my favorite conference talks is semi related to problems like this. https://www.youtube.com/watch?v=fE2KDzZaxvE Brian Cantrill - Zebras all the way down
Thanks. The article has lots of external links but not to the original reddit post...
Helium is very good at getting through the tiniest cracks due to its small atomic diameter. One uses it to find leaks in devices with ultra-high vacuum seals (e.g. in low-temperature physics) by attaching a pump with a simple mass spectrometer sensitive to Helium to the device under test and then using a small helium gun to test different parts of the device from the outside. When spraying it at the leak some of it is pushed inside by the pressure difference and can be detected by the pump spectrometer.
Hydrogen would be even better of course but it is rather dangerous when mixed with air.
Hydrogen would not be better. A helium atom is considerably smaller than a hydrogen molecule. Even if you could use atomic hydrogen, the helium atom's radius is significantly smaller due to the higher central charge that is only partially screened by the "other" electron.
Hydrogen binds with other hydrogen atoms to create H2 which is the only form of elemental hydrogen you’ll see outside of a lab helium is unique in that its singular atom is its own elemental molecule.
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Hydrogen would be better. Size isn't the most important factor. Gasses with low molecular mass have higher particle velocities. The velocity affects mixing, passage through holes (including filters), and the speed of sound. Hydrogen is about 2 AMU, 1 for each atom, while helium is about 4 AMU.
You can find the formulas in a typical college chemistry textbook.
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It gets worse than that when your cryo equipment has a “cold” helium leak. Ie, something leaking on the dilution fridge only at helium temperatures (4.2K) and lower, but no trace of a leak at room temp.
Repeated bouts of guessing where the leak might be and trying to plug it (usually by welding or re-machining some part), cooling down, checking if it worked, warming up, ripping some more of your hair out, repeat.
Yeah I had that as well, in that case it was best to replace all the Indium seals right away as like you said it takes 24 hours to do a full cooldown/warmup cycle anyway, so spending a day to make new seals is often faster. That's a part of low-temperature physics I definitely don't miss!
I worked on a system where I needed to reach and maintain pressures of 10^-3 tort, and that was hard enough. I can’t imagine having to deal with helium sensitivity.
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It's why companies that do stuff with ultra-low-temperature pressure vessels typically dramatically overengineer the devices.
Electronic parts also get helium exposure on the launch pad in a rocket. I know for example there can be helium sensitivity issues on gyros for CubeSats.
Wouldn’t hydrogen only work if it was atomic hydrogen? I thought molecular hydrogen gas was larger than helium.
Hydrogen is soluble in most metals. It will just diffuse right into it, like air flowing through a foam filter.
Added bonus: if the metals in question form chemical bonds with hydrogen, (titanium in particular) it will happily do so, even if it's deep inside the metal. The metal will turn very brittle very quickly if it's exposed to molecular hydrogen.
https://en.wikipedia.org/wiki/Hydrogen_damage
Even a single hydrogen atom is bigger than a single Helium atom. The charge of the helium nucleus is higher and thus "pulls" the two electrons further inward than Hydrogen's single proton pulls its single electron.
Hydrogen exists as H2 in its elemental form you’ll you’ll need to ionize it to separate it and keep it in an ionized or other way isolated form to prevent it from binding to other hydrogen atoms.
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As a bonus hydrogen is higly explosive, helium is not.
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Maybe I'm just a fanboy, but I found one of the most impressive parts of the story, aside from actually tracking down the root cause, was that the iPhone User's Guide actually specifically addresses this, along with explaining that it's necessary to give it about a week for the helium to diffuse.
You just know there was a days-long meeting about "the Helium problem", including graphs of how likely different user-personas are to enter a zeppelin, work in a balloon factory, or attend exceedingly well-funded birthday parties.
After debating late nights about whether to pony up for the new better-sealed clock, someone said "Screw it, throw it in the user agreement."
"better sealed clock" would be the universally used quartz resonator, but that would have added 0.002$ to their cost. Unthinkable.
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I think that sticking iPhones in helium balloons is now going to the top prank of 2019.
They probably got that info when they bought their oscillators. From there it should be pretty straight forward to include it in testing procedures.
I feel like the buried lede is that the MRI operators vented large quantities of helium into the hospital's HVAC and didn't think to tell anyone.
Oxygen monitors are standard practice when you have MRI machines and Helium cooling. I would like to assume that this monitoring was in place and it never raised any flags? https://www.pureairemonitoring.com/helium-mri-rooms-around-w...
The air’s usual O2 concentration is ~20.5% and it looks like safety monitors trigger at 19.5% and 18%: https://www.pureairemonitoring.com/all-categories-gas-monito...
Helium makes up less than 0.0005% of air naturally. I’m guessing that increasing He concentration 1000 times to 0.5%, for example, is enough to cause problems for iPhones, but not enough to trigger the alarm or pose any danger to people.
Breathing helium is completely safe as long as the oxygen concentration is near normal. Hospitals have occasionally even put patients with respiratory disorders on helium/oxygen breathing mixtures because the work of breathing is slightly lower than air.
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Considering that Trimix and Heliox used in deep commercial dives can have the majority (Aka >50%) of the breathable “air” be helium, your theory that there’s really any risk of danger to people seems a bit unwarranted to me.
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Not enough to directly endanger people, but a hospital is full of electronics that plenty of people need to live, and it sounds like they could potentially share the iPhone’s vulnerability.
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Unfortunately the O2 sensors were being monitored by an iPad.
Or the O2 alarms just don't work and the hospital was negligent.
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Indeed. I had to reread that paragraph. That's a LOT of helium (by volume).
"So, i noticed some of the workers' iwatch's weren't registering the users' heart-rates. At first, I thought it was because they had all died from suffocation from the massive gas leak. But, then I discovered something interesting... it was actually the helium molecules worming their way into the internal clock chip! Amazing day."
Yeah, but at the same time, it wasn't enough to set off the alarms for low oxygen content, which is at least a little disturbing, right?
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What a relief that must have been.
Another scary practice is venting natural gas indoors. Most of the time it's fine, but sometimes you get a catastrophic explosion: https://www.youtube.com/watch?v=rjxBtwl8-Tc (The US Chemical Safety Board has a bunch of interesting videos.)
This is nuts! Why would you even vent flammable gases indoors on a construction site?!
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They thought they were venting outside. It only went inside because of an undetected leak.
As long as he helium doesn’t displace the oxygen it is fine. Saturation diving has people living in “heliox” environments where the atmosphere is helium and oxygen.
There are more details in the original thread https://www.reddit.com/r/sysadmin/comments/9mk2o7/mri_disabl... on reddit:
I discovered that the helium leakage occurred while the new magnet was being ramped. Approximately 120 liters of liquid He were vented over the course of 5 hours. There was a vent in place that was functioning, but there must have been a leak. The MRI room is not on an isolated HVAC loop, so it shares air with most or all of the facility. We do not know how much of the 120 liters ended up going outdoors and how much ended up inside.
Except that Helium is not dangerous whatsoever and to actually displace oxygen you would need much much more than that.
Venting 120l of liquid helium (or about 84,000l of gaseous helium) really isn't that much of a health concern
I've seen multiple vents of ~1500l of liquid helium (~1,050,000l of gaseous) in a single day from a couple bad MRI units when I worked at a company that makes them
Only "dangerous" place to be was in the fragmentation path of the burst disc (which was enclosed in the top of the unit (at the time)), or directly in the path of the nearly-liquid (ie extremely cold) helium as it vented
It dissipates extremely rapidly
Yea, that sounds incredibly dangerous considering how easily you can suffocate inhaling helium
how easy is it? It floats, so it only fills a room from the top down... and if you fall over unconscious, you're automatically moving to a part of the room with more oxygen. it would have to displace all of the air in a room in order to suffocate someone, no?
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Right! It's not like an "allergy" to helium is going to be a problem for any user at any time unless, you know, there's a big helium leak, at which point the phone is the least of your problems
Wouldn't this affect people's voices?
Eventually. But I would expect that by the time the effect is noticeable, the concentrations will be too high to support consciousness and will have been for some time.
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Considering the current helium shortage it's a shame they just wasted it.
This is the first time that I remember seeing a story evolve on the internet. What was originally from a post on r/sysadmin 3 weeks ago is now summarized on a Blog article that's at the top of HN. Will it get picked up my mainstream media and be on everyone's news feed by next week? Or tomorrow, now that its picked up momentum? Besides being a really fascinating story, its having an interesting journey as news travels through different outlets and gets condensed and filtered down to more consumable forms.
You weren't around when the Meltdown rumors started?
I remember hearing plenty of whispering that Intel had a major bug disclosure coming up, but for most of that time I feel like the majority of speculation was centered around the Intel ME.
Sadly my immediate reaction to this post on /r/sysadmin was to discount it, or rather attribute it to some external factor that nobody could possibly figure out and entirely unrelated to the MRI. In this case I was quite happy to be proven wrong by the follow up posts and subsequent article.
I'm really curious why something they can generalize to "helium leaking into the quartz oscillator" only affected Apple products. What feat of manufacturing keeps a broad range of OEMs safe on the Android side but so eludes Apple? Worse yet, was some "cost savings" engineered between iphone 5s and 6 that ultimately introduced this issue?
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No doubt it will move to mass media
We had this problem too.
Every time my colleague brought his phone to the control room the Cellular stops working for like a day or two, but my 6s worked just fine anywhere even next to a Dewar that's venting Helium. Now the mystery is solved!
BTW, among us there are others who accidentally brought their phones near or even into the MR bore during maintenance, but none of these devices has done any permanent damage to our phones, except one accelerometer on a cheap Chinese phone, even in a 7T magnet. So I never thought that MRI could be causing the problem.
It's in the iPhone user guide ... maybe not something everyone reads, but it has been known for some time
That said - a 120l leak of liquid helium is both stupidly expensive, and highly damaging to the MRI unit: there's a bath of ~1000-1500l of liquid helium in an MRI to keep the superconducting coils at superconducting temperatures. Losing ~10% of that volume probably means the unit won't work
When you install a new unit you use additional helium that boils off just to bring it to superconducting temperature.
>When you install a new unit you use additional helium that boils off just to bring it to superconducting temperature.
Nope - well, not with any of the ones with which I am familiar: they're shipped full most of the time
Few things; Isn't it a bit odd that a hospital MRI machine room isn't being monitored for these kinds of things? I'm curious, not accusatory.
Also, this could be a potentially catastrophic tool for terrorists. As trivial as it sounds, it's even worse than a traditional frequency jammer because it renders the device unusable instead of just not being able to communicate with the outside world.
Edit: On the other hand, interesting counter-terrorism tool as well. Is there any precedent for the CIA using this sort thing intentionally?
There are almost certainly oxygen sensors in that room. The helium concentration was probably not high enough to displace enough oxygen to trigger them. Though it wouldn't entirely surprise me if they were ignored or disabled.
Liquid helium is rather expensive and would likely draw attention in areas where it's not usually handled. Really doesn't sound like a useful terrorism tool.
Honestly, even Sarin nerve gas isn't a very useful terrorism tool.
I think the infamous Thunderf00t does a decent job of explaning why https://www.youtube.com/watch?v=l6uLUaqgWY0
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Thanks for the info! Did the article mention that it had to be liquid helium then?
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It was monitored. From the original thread https://www.reddit.com/r/sysadmin/comments/9mk2o7/mri_disabl... on reddit:
One of our multi-practice facilities is having a new MRI installed and apparently something went wrong when testing the new machine.
[...]
I discovered that the helium leakage occurred while the new magnet was being ramped. Approximately 120 liters of liquid He were vented over the course of 5 hours. There was a vent in place that was functioning, but there must have been a leak. The MRI room is not on an isolated HVAC loop, so it shares air with most or all of the facility. We do not know how much of the 120 liters ended up going outdoors and how much ended up inside.
The idea that some terrorists are plotting to ruin our phones with helium, and that we should consider it "catastrophic" is laughable.
Scaling a "helium attack" against electronics is one of the dumber terrorist plots I've come across. But let's play.
Say I scored a big truckload of helium, 5000 l. (The contents of my tank will expand to 3750 m3 of He gas.) Then I got access to a ventilation duct into the subway. I manage to hook up my tank and start depleting into the subway. Assuming 20 m2 cross-section for a tunnel: if I could do the emptying at once, I could fill 0.187 km of tunnel completely with He; killing all vermin in that section.
But hey my goal is not to suffocate (that would be boring, right?) but to fritz electronics. So I do it slow and steady into a station. Say I want to keep the concentration of He in the station at around 0.1%. (I assume it would take time for operators to detect this. I don't know how sophisticated gas detection is in subways.) Let's assume an airflow of 5 m3/s into that station. I'd need 0.005 m3/s He or 400 m3 per day to keep the level at 0.1%. So for only one day, I'd need to get around 500 l liquid helium into position.
There are easier pranks to play.
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Lol you clearly underestimate some people, but I'm wondering what makes you think that even a frequency jammer in the wrong hands couldn't be potentially catastrophic?
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I love HN. I came here to learn more about MEMS RTCs, something I've never heard about previously... But most of the discussion is about the dangers of a helium leak... Which is a good point, especially if that leak is in a hospital.
A bit of googling on MEMS RTC revealed this slightly dated article which I thought was still interesting: https://www.maximintegrated.com/en/app-notes/index.mvp/id/55...
Turns out one of the main reasons to switch is for the smaller packaging vs quartz oscillators.
The picture in the article that is labeled as an MR scanner is a CT scanner, and the people are wearing lead for radiation protection.
The photo is labeled "Morris Hospital’s GE Medical BrightSpeed CT Machine"
It said ‘MR’ rather than ‘CT’ when I commented, and now it’s a completely different photo with a new caption.
It's good that he was able to reproduce it (although with a far higher concentration of helium), but the original story showed up a few weeks ago at an EE forum I lurk, and everyone there was skeptical of helium and suspecting EMP instead:
https://www.eevblog.com/forum/chat/helium-in-the-air-kills-i...
But an electromagnetic pulse would have taken out medical equipment in the facility as well, and they were working fine!
I suspect medical equipment is designed to a higher standard of EMP resistance than most other products, especially equipment designed to sustain life. Phones also have antennae specifically designed to pick up EM fields, while medical equipment like an EEG or ECG is specifically designed to reject them.
Likewise, the devices "reviving" after a week is not unusual if they're just resetting due to power loss. Immediately disconnecting and reconnecting the battery would for sure differentiate between helium (device remains dead even after reset) and EMP (device reboots successfully.)
But Android phones were also unaffected.
Any particular reason you're ignoring the fact this only happened to iOS devices? Do the various Android manufacturers incorporate additional shielding to prevent the occasional EMP?
It probably affects a specific chip Apple are using that may not be present in the Androids.
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If the issue were specific HF then it could be a geometric feature.
Am I the only one hoping that exposure to helium made Siri sound like a chipmunk?
Anybody can provide a reason why SiT1532 wouldn't be hermetically sealed? They are talking about high accuracy, intuitively it would seem that if helium affects it this badly, then it would be susceptible to some atmospheric pressure changes (unless the seal worked against air but not helium).
They do have a strong hermetical seal on them, but the older ones used by Apple are still susceptible to “small gas molecules”.
They must have some seal in place and fortunately our air is Nitrogen, O2, and a little bit of Argon. These can’t get through the seal! Helium is only found in minuscule amounts naturally and apparently this concentration is so low it doesn’t matter.
Helium is special because is it has the smallest kinetic diameter of all the noble gases. You can compare its diameter to other gases here: https://en.wikipedia.org/wiki/Kinetic_diameter#List_of_diame...
Helium is frequently used in leak tests since it has a way of working through even the tiniest of leaks. Elemental Hydrogen is of course smaller, but I believe you only find Hydrogen as H2 which is a larger molecule than Helium.
According to that table, Helium is 260, and water is 265, and there are a few more under 300.
Does that mean that water (in some form) also acts like helium and would be able to get through that seal?
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Sealing against Helium is vastly more difficult than sealing against air, as air is made out of molecules of rather large atoms, while Helium gas consists of single small atoms. That is why divers watches often have a "helium escape valve". The watches are sealed against high pressures of water or air. But when worn in pressure chambers where divers live on a mix of high pressure helium and oxygen, the helium gets into the watch. When depressurizing at the end of the pressure chamber time, the helium pressure could blow the watch crystal from the watch if not released by the escape valve. For a similar reason pilot watches have special fastening of the watch crystal, so that underpressure doesn't lift it off.
Those helium escape valves are just for marketing overpriced toys to pretentious wannabes. Most working saturation divers haven't used fragile, expensive mechanical wristwatches for decades now.
The seal works against air but not hydrogen or helium because the molecules are so small they'll diffuse through pretty much anything.
It's really hard to contain helium. It'll leak through pretty much any solid material.
is mylar special? a good mylar balloon can float for weeks
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>(unless the seal worked against air but not helium).
That is exactly the case. From the article, helium (and to a lesser degree, hydrogen) have very very small molecules and are able to slip past very small imperfections in hermetic seals.
I would be very interested in seeing the the iPhone charges while "anethitized". I severely doubt data would be accessible via standard channels, but as this kills the general clock I am assuming it should prevent any sort of lock protection mechanisms from kicking in indefinitely.
Not sure how you would get it going again and / or how necessary that would be. Perhaps heating it to excite the helium trapped in the oscillator and hoping it bounces out.
Could end up being a pretty easy go to law enforcement trick. Put a phone and a helium balloon in a ziplock bag, pop the balloon, pause the phone, deal with it later
We were wondering if this could be used for iPhone scams. It's a dead-simple way to apparently fatally & totally destroy in a deep & non-diagnosable way a pristine iPhone which will however (probably) reverse itself in a few weeks. It seems like this ought to be exploitable somehow. Something like get a new iPhone, helium it, return it for a refund, and somehow hold onto the phone... Couldn't figure out how it would actually work, though.
how about get a phone, accumulate normal life scratches for 9 months, "helium it" hard, so it lasts a while, then get apple to replace it as defective? iiiiiii dunno... there's a scam in there somewhere, were just not being creative enough!
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Depends on the how the charging controller is implemented. There is, at the very least a state machine -- if not an MCU -- managing the charging process. So I think it's highly unlikely to _start_ charging with the clock stopped, and one would hope there are some analog triggers to halt charging (eg. battery over-voltage) if the clock stopped while it was charging.
A smaller discussion on the Reddit thread that this comes from: https://news.ycombinator.com/item?id=18334630.
It was really fun to watch this story develop over the last few weeks on /r/SysAdmin. I found myself checking the OP's profile a few times a week waiting for the smallest update. It's truly mind boggling to me (a software developer with very very limited hard science experience) to think about the ramifications of invisible forces causing these kinds of wild goose chase mysteries.
>the 120 liters ended up going outdoors and how much ended up inside. Helium expands about 750 times when it expands from a liquid to a gas, so that’s a lot of helium (90,000 m3 of gaseous He).
the math seems couple orders off - the 120l would make less than 900m3. The 90000m3 would be on the scale of the total volume of a multi-story hospital building.
Three, in fact.
120 × 750 = 90000 liters, or 90 m^3. Very annoying.
This article isn't great.
First, it illustrates an MRI story with a (mislabeled) picture of a CT scanner.
Then, it overestimates the volume of gas expelled by a factor of 1000.
170L X 750 = 90k L = 90m^3.
This would fill a 35m^2 (about 350 sq ft) room, maybe the size of a living room, with pure helium.
I came up with 125 m^3 here:
http://www.airproducts.com/Products/Gases/gas-facts/conversi...
But if you're going to criticize their math, you might want to double check your own math.
90 m^3 = 2m (height) x 6.7 m^2
(ok, 2m is a little low, 2.5m would be more comfortable.)
My math was fine, but I did get the base numbers wrong. Should have been 120L as mentioned in the article, which equates to 88.577 m^3 at 15C, which is pretty chilly. 20C is more like room temp.
But, I'm not sure your math is quite on the money either.
Wow. This is good to know. As a TriMix SCUBA diver, we should keep our iPhones away from the fill station and away from us when we are venting / testing our mixes :-)
Aman! Had the exact same thought and glad this story brought it to my attention.
This is strange and I happen to work at a facility that does a lot of open air helium mass spectrometer leak testing.
I'm and Android user so I have no skin the the game. I'll have to talk to some people at work tomorrow. A few guys are iPhone users and work in direct proximity to the helium leak testing stations or use them as well. I know a woman in the office didn't like her iPhone because of numerous problems but I never thought to press her for details.
Would the helium concentration in air actually get high enough to cause problems? As far as I understand leak testing, you don't need a lot of helium for that to work.
Not much at all but some of the knuckleheads try to speed up the process and crank the pressure until the helium probe is more of a blow gun.
That’d be an interesting way to defuse a bomb hooked up to an iPhone with a power-off failsafe
Anthropomorphizes the iPhone when you think about how humans react to gaseous general anesthesia https://en.wikipedia.org/wiki/Isoflurane
> “My immediate thought was that the MRI must have emitted some sort of EMP, in which case we could be in a lot of trouble."
I... don't think that's a thing that MRI machines can do. They're even shielded!
> Perhaps there’s a bug in iOS that causes crashes when it gets faulty data from the gyro? But the bug impacted Apple Watches, too—and they run WatchOS.
Technically, watchOS is iOS
TL;DR: Apple uses MEMS clocks (while most Androids contain quarzes), which can be affected by Helium molecules even though they are sealed in the attempt to prevent that.
How will I ever execute my plan to explore the eroding atmospheres of exoplanets when apple can’t even be bothered to handle a little helium. Jeez...
Nice discovery! Now scifi/horror movies can stop using the "I have no reception for no reason" and use helium somewhere in the plot.
It was very entertaining to follow r/sysadmin's threads about this weird issue, until the guy found out the source of the problem.
I think we just invented a way to get people to put away their phones during concerts, plays, and comedy shows.
So what's the most effective means we've found to seal against helium penetration?
So I guess IPhone owners need to stay away from children's birthday parties?
I wonder how aware Apple is of this story. I'm sure engineers browsing here will have seen it, but it'll be interesting to see future iFixit teardowns of devices to see if the MEMS sensor has any different shielding or if they use a different chip entirely.
The article says that Apple's user guide mentions phones not working around helium:
Exposing iPhone to environments having high concentrations of industrial chemicals, including near evaporating liquified gasses such as helium, may damage or impair iPhone functionality.
Reddit > ifixit > Hackernews > Buzzfeed/Engadget tomorrow?
Couple of days after Engadget it'll be on mainstream.
It's a little hard to take this article seriously when the caption grossly misidentifies a GE BrightSpeed CT scan (x-ray) with a MRI machine. My guess is the magnet was still on (perhaps incorrectly).
Those MEMS device photos (micrographs) are beautiful.
I think the correct spin would be to say:
Apple Devices are Helium Detection Canaries.
It would be an interesting attack if you needed to disable an iPhone.
Any security hardware using this oscillator would be at risk too. I can see the Mission Impossible plot to use it to attack a security systems and IP cameras if they used those chips.
I'm not sure how far this vulnerability will ever get an attacker because most devices will probably continue to use regular quarts oscillators that aren't sensitive to this like MEMS devices. Apple probably only uses them because they're squeezing every ounce of space and their markups can stand the increased cost of the MEMS vs the quartz/ceramic oscillators.
Maybe not a good idea to use MEMS avionics on a blimp or dirigible, then.
Here's the Zeppelin NT cockpit, but I can't tell what kind of gyros they may be using: https://upload.wikimedia.org/wikipedia/commons/3/33/2003-07-...
Iphones are allergic to mercury.. like everything milled from alluminium
all 40 devices got helium in them at the same time
This is hilarious, additionally the software quality of iDevices have gone down the tube.
From where do they know the guy's name and where does he work?
They probably contacted him through Reddit.
"Hospital cooling gas caused cardiac arrest in fresh Apples."
Hospital cooling gas caused clock arrest in fresh iPhones.
well, ticker is ticker ;)
Did iFixit just take a post from reddit and put it on their website?
Did they add anything to it, the write up was quite comprehensive. I’ve got a bad feeling about this.
What is it about Helium that breaks the device? Is the device intended to contain a vacuum?
The microscopic oscillating part in the clock needs a vacuum. Having air around would dampen the vibrations too quickly because the mass is tiny, and the timing would vary with air pressure or humidity.
It sounds like microelectromechanical devices (like the quartz oscillators that keep time in electronics) are so small, and built to such fine tolerances, that helium atoms can literally, physically jam them like sand in a gearbox. That's what the article seems to be saying, anyway.
I guess they're fine under normal conditions because typical atmospheric molecules are actually too big to get inside? I'm not clear why the particular clock that Apple used is susceptible but other ones aren't. I guess they're sealed better.
Other devices use a solid-state quartz oscillator. This is a hollow mechanical frequency generator.
Did you read the article? It's all explained there.
TL;DR: it breaks the oscillator that keeps time on the device. This breaks the clock and eventually has a cascading effect on the system.
The article is pretty straightforward and engaging; it's worth a read!
Hey, thanks! I had fun researching it.
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Oh wow, so the clock is unnecessarily coupled to the other systems?
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Helium molecules are small enough to cause issues with iOS devices' internal clock.
> Hydrogen and helium are notoriously hard to contain because their molecules are so small.
You probably didn't mean "helium molecule"–or if it was, that would very odd, as helium as a molecule is very rare…
I've heard plenty of good chemists refer to monatomic gases (and sometimes ions) as molecules, or "molecular", colloquially, and particularly when talking generically in terms where they could be replaced by another gas. That helium is monatomic is both well understood and not especially relevant in many contexts.
He2 is rare enough that the few times I've heard it spoken about, people have usually said "helium dimer" to make it clear that's what they mean. Since that's the rare case, it's the logical one to be explicit about.
> I've heard plenty of good chemists refer to monatomic gases (and sometimes ions) as molecules, or "molecular", colloquially, and particularly when talking generically in terms where they could be replaced by another gas.
I have also seen this, but it has normally been almost exclusively confined to when people talk about the "particles" of gas from a kinetic theory point of view.
A single-atom molecule is a very simple molecule. But it is a molecule: "The smallest part of any substance which possesses the characteristic properties and qualities of that substance, and which can exist alone in a free state."
Molecular helium happens to be identical with atomic helium, where an atom is the smallest unit of an element (not a chemical substance).
Water (H20) is a substance whose smallest unit is a molecule of 1 oxygen + 2 hydrogen atoms. Helium is a substance who's smallest unit is 1 helium atom.
Generally molecules are required to consist of at least two atoms bound bound together. For example, here's what Wikipedia defines them as:
> A molecule is an electrically neutral group of two or more atoms held together by chemical bonds.
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Hydrogen molecules (2 atoms) are much larger than the single-atom helium molecules. This is why helium gas is uniquely difficult to seal.
Yep that's why you need to get your kids party balloons on the same day as the party.
The best kind of correct...
Do you think anyone's understanding was negatively impacted by the use of the word 'molecule' here?
No, not really. But I thought it might be an interesting point to share.
Helium is a 'noble element', check the Periodic Table and tell me how Helium gets to be part of a molecule. Unless a lot has changed since I was at school then you aren't going to get a lot of helium 'molecules'. It just doesn't work like that.
What I don't get is how these helium molecules diffuse into the iPhones so easily, an awful lot of helium must have to leak for that. Normally helium - balloon sized quantities - tends to prefer going skyward rather than hide in an iPhone.
But since that seems to not be the case it would be good to turn up at a concert where everyone is playing with their hand rectangles rather than enjoying the moment, then to release some helium to fix that for them...
> Helium is a 'noble element', check the Periodic Table and tell me how Helium gets to be part of a molecule. Unless a lot has changed since I was at school then you aren't going to get a lot of helium 'molecules'. It just doesn't work like that
Yeah, well maybe they don't tell you all the details and special cases in school...
https://en.m.wikipedia.org/wiki/Noble_gas_compound
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I am well aware that helium is a noble gas, and generally does not form molecular compounds. Under the right conditions, though, helium can from molecules bound with the van der Waals force: https://en.wikipedia.org/wiki/Helium_compounds
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