Fermi Labs called one day wondering why a 'smart' pressure transmitter lost its memory every time they ran a test. I drove over and the guy took me up to the 3rd or 4th floor balcony overlooking the 'test' area. Opposite the balcony was an electromagnet several times the size of a mansion, its height reached to the roof.
He pointed to the lower left corner and said that the transmitter was down at the floor level at the oorner of the magnet.
The area was plastered with warning signs about the prohibition of any metals, particularly ferrous metal, on your person during tests because the magnetic field would attract the object.
The guy was quite disappointed that I wouldn't involve the manufacturer in 'testing' the transmitter for operation in dense magnetic fields, when his application could not be reasonably duplicated. His was the 'test' site and the result was that the memory was wiped every time the magnet fired up. He asked how to shield it to work in that environment and I passed, it wasn't my job to tell him how to shield it - they're the ones working with massive magnets on a day-to-day basis.