Morris Hospital. Chicago. It’s a pretty normal day for Systems Specialist, Erik Wooldridge, until the installation of a new GE Healthcare MRI machine that is. During the installation, he starts getting calls that cellphones throughout the hospital aren’t working, iPhones in particular. Shortly thereafter, Apple Watches start glitching.
Initial thoughts are that the MRI emitted some kind of EMP (electromagnetic pulse), but if that were the case it would have affected all electronics in the hospital, such as appliances and medical equipment, not just Apple products. These strange phenomena called for an investigation and Wooldridge was on it.
Wooldridge writes on Reddit that 40 different devices were impacted, all Apple, and that the technician’s Android phones were just fine. Most of the devices were dead and showed no signs of charging when plugged into outlets. When devices did manage to turn on, they experienced cellular interference but got a strong wifi signal.
Reddit speculates that it could have been caused by liquid helium, a fluid used in the cooling of MRI machines. Wooldridge investigates only to find that there was, in fact, a helium leak at the same time during the time that the devices went haywire.
“I discovered that the helium leakage occurred while the new magnet was being ramped,” wrote Erik Wooldridge on Reddit. “Approximately 120 liters of liquid 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).”
Why would helium have an effect on these devices? It’s because helium interacts with the microelectronics inside of smartphones. These microelectromechanical systems, or MEMS, drive the main processor clock in smart devices and measure time. According to Reddit user captaincool, the mechanical resonator must be inside a tiny hermetically sealed chamber with either a controlled gas or a vacuum inside to function properly. However, because of costs and physics, the seals aren’t perfect and can be permeated by small atomic gasses like helium.
User guides for the iPhone and Apple watch do actually point out this vulnerability.
The question remains though: why only Apple? Kyle Wiens of ifixit.org looked into the matter and speaking to the company that makes the image stabilizing chip in the Pixel 3, InvenSense Motion, confirmed that this was a problem across multiple devices. It’s all due to the fact that helium’s molecules, and similarly hydrogen, are incredibly hard to contain because they are so small.
So, just to be safe, you should steer clear of gasses with smaller molecules like diatomic hydrogen and monatomic helium if you want to keep your phone safe and in working condition.