And yet that floor had better be very solid indeed. Superconductive MRIs present their own unique hazards. The superconductive coils are supercooled with liquid helium. The MRI's technicians might be smothered or frozen by boiling helium, so it has to be vented out the roof, requiring the installation of specialized vent-stacks. Helium leaks, too, so it must be resupplied frequently, at considerable expense.
Some scanners feature elaborate telecommunications equipment.
Like the giant scanners themselves, all these associated machines require power-surge protectors, line conditioners, and backup power supplies. Fluorescent lights, which produce radio-frequency noise pollution, are forbidden around MRIs. MRIs are also very bothered by passing CB radios, paging systems, and ambulance transmissions. Despite all these drawbacks, the United States today rejoices in possession of some two thousand MRI machines. Five million MRI scans were performed in the United States last year, at prices ranging from six hundred dollars, to twice that price and more.