SAR and induced current distributions for operator exposure to RFdielectric sealers

The finite-difference time-domain method is used to calculate local, layer-averaged, and whole-body averaged specific absorption rates (SARs) and induced current distributions in a 16-tissue, anatomically based, 5628-cell model of a human to assess operator exposure to RF sealers. Industrially relevant shapes and dimensions of commonly used RF dielectric heaters using parallel-plate and bar-type electrodes are considered. Realistic postures of the human operators are used for the calculations, including extending arms to simulate working conditions or an operator sitting on a wooden or metallic stool. Due to the high-intensity leakage fields in proximity to the RF applicators, some of the highest induced currents and SARs are calculated for the hands and the ankles and, in the sitting position, the knees. It is concluded that steps should therefore be taken either to reduce the leakage fields or shield the hands and the knees if it is necessary for them to be in high leakage field regions