The induced current in an anatomically human model of 2.5x2.5x2mm voxel size for exposure to intermediate frequency magnetic fields produced by a household induction heater is computed by the impedance method. Although magnetic fields due to the induction heater have components caused by the fundamental (20.9kHz) and its harmonic frequencies，the Fundamental frequency component only is considered to investigate induced currents in this paper. Magnetic field with the maximum value of about 2μT near the lower abdomen of the body was assumed based on the B-field profiles measured around the practical induction heater. According to ICNIRP guidelines，the basic restriction is expressed in terms of a current density averaged over a cross-section of 1㎠ perpendicular to the direction of the current. Proposed in this paper is the procedure to convert the computed results into the corresponding current densities that are averaged over the cross section of any l ㎠of the model. It is found from the numerical results that the maximum value，5.31mA/㎡，of the averaged current densities appears at the muscle of the abdomen which is close to the magnetic sources. This value is 1/8 of the ICNIRP basic restriction for the public exposure. It is also indicated that the averaging treatment proposed causes the significant decrease in computed results at a certain voxel. In the present case，the maximum value obtained with the averaging treatment decreased by 60%，i.e., from 13.2mA/ ㎡without the averaging treatment to 5.31mA/㎡.

View full abstract