[Safety aspects in MR imaging]

With the growing number of Magnetic Resonance Systems in operation in clinical practice, safety aspects gain increasing importance. Therefore, it is necessary to evaluate possible risks and effects on human health. After an introduction to the basic principles and techniques involved, the various effects on biological systems and especially the human organism caused by the static magnetic field, the alternating magnetic fields and the high frequency fields required are described on the basis of current literature and partially also on our own experience. Basic information for the safe operation of diagnostic Magnetic Resonance Systems is presented. Limits for exposure to magnetic fields and time-dependent changes of electromagnetic fields for patients and employees as suggested by health authorities are given.