Impedance method computation of induced currents in a simple model of a child exposed to electromagnetic fields of an electric blanket

Health Phys. 1996 Nov;71(5):676-84. doi: 10.1097/00004032-199611000-00006.

Abstract

The three dimensional impedance method has been used to calculate the distribution of induced current densities in a simple model of an 8-y-old child exposed to the electric and magnetic fields of an electric blanket. Two types of electric blankets have been modeled in the calculations, the pre-1989 conventional type and the presently available low magnetic field PTC (positive temperature coefficient) electric blanket. The purpose of this study was to calculate and compare the induced current densities in the model of the child due to the two types of blankets and also to compare the contributions to the induced currents by the electric and magnetic fields produced by the two types of blankets. The computations have shown that as expected and claimed, the induced current density in the model of the child due to the magnetic field of the low magnetic field PTC electric blanket is much lower than the induced current density due to the magnetic field of the conventional electric blanket. However, the computations have also shown that the contribution to the total current density by the electric field of the low magnetic field electric blanket is slightly higher than that due to the electric field of the conventional electric blanket. Hence, the total average induced current density due to both the electric and magnetic fields in the case of the low magnetic field PTC electric blanket is about one-third that in the case of the conventional electric blanket.

MeSH terms

  • Bedding and Linens / adverse effects*
  • Child
  • Electromagnetic Phenomena*
  • Humans
  • Models, Structural