ICNIRP Guidelines GUIDELINES FOR LIMITING EXPOSURE TO ELECTRIC FIELDS INDUCED BY MOVEMENT OF THE HUMAN BODY IN A STATIC MAGNETIC FIELD AND BY TIME-VARYING MAGNETIC FIELDS BELOW 1 HZ

INTRODUCTION IN THIS document, guidelines are established for the protection of workers moving in static magnetic fields or being exposed to magnetic fields with frequencies below 1 Hz. This includes, but is not limited to workers engaged in activities related to magnetic resonance imaging (MRI). The general principles for the development of ICNIRP guidelines are published elsewhere (ICNIRP 2002). SCOPE The main objective of this publication is to provide guidelines for protection of workers against established adverse direct health effects arising from exposure to static magnetic fields and time-varying magnetic fields below 1 Hz and to avoid sensory effects which may be annoying and impair working ability. A two-tier approach is suggested , with a relaxation of the restrictions in conditions where the workers are made aware of the biological consequences of exposure and are trained to control their own behavior (ICNIRP 2009a; Jokela and Saunders 2011). The guidelines are not expected to be relevant for the general public because all exposures to intense magnetic fields below 1 Hz are currently found at workplaces. The guidelines do not apply to the exposure of patients undergoing medical diagnosis or treatment. Detailed considerations of protection of patients undergoing MRI examinations are given in separate ICNIRP statements (ICNIRP 2009b, 2004). It is also recognized that, for research purposes, there might be a wish to investigate the effects of static magnetic fields exceeding the basic restrictions presented by these guidelines (ICNIRP 2009a); such experimental exposures, however, are a matter for the appropriate ethics committees (institutional review boards). Compliance with the present guidelines may not necessarily preclude interference with, or effects on, medical devices such as metallic prostheses, cardiac pacemakers, implanted defibrillators and cochlear implants. ICNIRP recognizes that practical policies need to be implemented to prevent inadvertent harmful exposure of persons with implanted electronic medical devices and implants containing ferromagnetic material and from dangers of objects unintentionally moving because of attraction by the magnetic force. Advice on avoiding these problems is not within the scope of the present document but is available elsewhere (IEC 2010; Shellock 2012). These guidelines will be periodically revised and updated as advances are made in the scientific knowledge concerning any aspect relevant for limiting exposure of static and time-varying magnetic fields below 1 Hz. The basic physical law associated with the induction of electric fields by a magnetic field is Faraday's law, which indicates that the induced electric field is …