IIRC, for fields >5T the movement of your blood is enough to induce currents you can detect as a weird tingling in your tongue.
Probably still safe, but it’s not as clear as I had previously assumed.
Probably still safe, but it’s not as clear as I had previously assumed.
When I would put humans in our 7T machine they'd sometimes feel their leg kicking during the acquisition. Because it's actively shielded with a pretty steep magnetic field from 0 to 7T you have to advance them into the scanner very slowly otherwise they can become very uncomfortable and nauseous.
Blood is a conductive fluid. When you move a conductor through a magnetic field there is an electric current induced.