Static magnetic field
The static field is always present on conventional superconducting MRI systems. Ferromagnetic objects can become projectiles, and implants or devices may experience force or torque. Access control and screening are therefore fundamental parts of MRI safety practice.
RF energy and heating
RF transmission deposits energy in the patient and can produce heating. Scanner operating modes, sequence design, patient characteristics, conductive loops, cables and contact points all matter. Manufacturer conditions and institutional policies must be followed for devices and implants.
Gradient fields
Rapidly changing gradients can induce peripheral nerve stimulation and produce substantial acoustic noise. Hearing protection and system safety limits are part of routine MRI operations.
Implants and device conditions
MR labeling may include MR Safe, MR Conditional or MR Unsafe designations. Conditional devices can require specific field strength, spatial gradient, SAR or B1+rms limits, coil restrictions, positioning, scan duration or other conditions. Device-specific documentation should be verified rather than inferred.
Educational scope
CoolMRIStuff safety content is for education and conceptual learning. It does not replace current manufacturer labeling, institutional policy, formal MR safety training, an MR Medical Director, MR Safety Officer, or qualified clinical judgment.