Reddit user harritaco discovered something rather unusual about the iOS devices used at their place of work. iPhones and Apple Watches stopped working unexpectedly, completely locking up and recovering only days later, sometimes suffering long-term harm.
The failures appeared to coincide with the installation of a new MRI (magnetic resonance imaging) machine. MRIs use powerful magnetic fields and helium-cooled superconductors, and something about the presence of this new machine was upsetting the Apple hardware. That magnets can be a problem for electronic devices is no big surprise—they can damage magnetic media, confuse compasses, and induce electric currents in harmful ways—but surprisingly, it’s not the magnets that seem to be the problem this time—it’s the helium.
The iPhone user guide warns that proximity to helium can impair functionality and that to recover, devices should be left to air out for a week or so in an environment far away from the rogue helium. Harritaco discovered that, during installation of the MRI machine, some 120 litres of liquid helium leaked and vented into the environment. This created a relatively high helium concentration, and any Apple hardware exposed to that helium stopped working.