- (e.g., high - frequency surgical equipment, short-wave therapy equipment, inside the RF shielded room of an MRI system) • Military areas (e.g., submarines, radar installations, weapons control systems) • Heavy industrial areas (e.g., power plants, steel and paper mills, foundries, automotive and appliance manufacturing, smelting and mining operations, oil and gas refineries) • Aircraft environments (e.g.,飞机,直升机)