An object that deflects 90 degrees 1 meter from isocenter on a 3T unit will be safer at which magnetic field strength?

In the context of MRI safety, the magnetic field strength of the MRI unit is directly related to the strength of the magnetic forces acting on ferromagnetic objects. This relationship means that the stronger the magnetic field, the more significant the deflection of a ferromagnetic object as it approaches the magnet.

When considering an object that deflects 90 degrees at 1 meter from isocenter on a 3T MRI unit, moving to a lower magnetic field strength, such as 1.5T, will inherently reduce the magnetic force acting on that object. Therefore, at the lower field strength of 1.5T, the object would be less likely to deflect as much or at all. This results in a safer environment, particularly for patients and personnel in the MRI suite, as the risk of the object becoming a projectile is significantly diminished.

Safer field strengths limit the likelihood of dangerous interactions between magnetic fields and ferromagnetic materials, making the practice of MRI safer for all involved. In summary, a strength of 1.5T is safer than 3T because the amplitude of the magnetic forces is less at lower field strengths, leading to reduced risk of projectile motion and related hazards.