If you’re one of those people that actually reads the iPhone user guide, you’ll know that there are certain things you should keep your phone away from. That apparently includes 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,” the user guide says.
For many people, including Reddit user harritaco, this may come as a surprise. The Redditor shared earlier this month that after an MRI was being installed and tested at their workplace, around 40 people’s iPhones and Apple Watches stopped working. Only iOS devices were impacted. Android users didn’t experience any long-term issues, harritaco said.
“It doesn’t surprise me that a massive, powerful, super-conducting electromagnet is capable of doing this,” the Redditor wrote. “What surprises me is that it is only affecting Apple products.”
Another Reddit user, captaincool, wrote that the helium caused the issue because of its impact on microelectromechanical system, or MEMS, oscillators. These are the tiny devices that drive the phone’s clock. For the device to work properly, the mechanical resonator has be kept inside a hermetically sealed chamber, the Redditor explained, but the seals can still be permeable to gasses like helium.
In a Tuesday follow-up to their original post, harritaco said they could confirm the cause of the iPhone malfunction was indeed helium. They conducted some tests, which involved placing an iPhone in a sealed bag with helium. The phone locked up after about 8 minutes. This, along with the iPhone user guide and information from the MRI vendor, confirmed the theory on helium being the culprit, they said.
Apple didn’t immediately respond to a request for comment.