MRI disabled every iOS device in facility due to helium leak

This is probably the most bizarre issue I've had in my career in IT. One of our multi-practice facilities is having a new MRI installed and apparently something went wrong when testing the new machine. We received a call near the end of the day from the campus stating that none of their cell phones worked after testing the new MRI. 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. We're still waiting to hear back from GE as to what happened. This facility is our DR site so my boss and the CTO were freaking out and sent one of us out there to make sure the data center was fully operational. After going out there we discovered that this issue only impacted iOS devices. iPads, iPhones, and Apple Watches were all completely disabled (or destroyed?). Every one of our assets was completely fine. It doesn't surprise me that a massive, powerful, super-conducting electromagnet is capable of doing this. What surprises me is that it is only effecting Apple products. Right now we have about 40 users impacted by this, all of which will be getting shiny new devices tonight. GE claims that the helium is what impacts the iOS devices which makes absolutely no sense to me. I know liquid helium is used as a coolant for the super-conducting magnets, but why would it only effect Apple devices? I'm going to xpost to r/askscience~~, but I thought it might spark some interest on here as well.~~ Mods of r/askscience and r/science approved my post. Here's a link to that post: https://www.reddit.com/r/askscience/comments/9mk5dj/why_would_an_mri_disable_only_ios_devices/

UPDATE:

I will create another post once I have more concrete information as I'm sure not everybody will see this.

Today was primarily damage control. We spent some time sitting down with users and getting information from their devices as almost all of them need to be replaced. I did find out a few things while I was there.

I can confirm that this ONLY disabled iphones and apple watches. There were several android users in the building while this occurred and none of them experienced any long term (maybe even short term) issues. Initially I thought this only impacted users on one side of the building, but from what I've heard today it seems to be multiple floors across the facility.

The behavior of the devices was pretty odd. Most of them were completely dead. I plugged them in to the wall and had no indication that the device was charging. I'd like to plug a meter in and see if it's drawing any power, but I'm not going to do this. The other devices that were powering on seemed to have issues with the cellular radio. The wifi connection was consistent and fast, but cellular was very hit or miss. One of the devices would just completely disconnect from cellular like the radio was turned off, then it would have full bars for a moment before losing connectivity again. The wifi radio did not appear to have any issues. Unfortunately I don't have access to any of the phones since they are all personal devices. I really can only sit down with it for a few minutes and then give it back to the end user.

We're being told that the issue was caused by the helium and how it interacts with the microelectronics. u/captaincool and u/luckyluke193 brought up some great points about helium's interaction with MEMS devices, but it seems unlikely that there would have been enough helium in the atmosphere to create any significant effects on these devices. We won't discount this as a possibility though. The tech's noted that they keep their phones in plastic ziplock bags while working on the machines. I don't know how effective they would be if it takes a minuscule amount of He to destroy the device, and helium being as small as it is could probably seep a little bit in to a plastic bag.

We're going to continue to gather information on this. If I find out anything useful I will update it here. Once this case is closed I'll create a follow-up as a new post on this sub. I don't know how long it will take. I'll post updates here in the meantime unless I'm instructed to do otherwise.


UPDATE:

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. 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).