Protection standards for radiofrequency electromagnetic radiation are principally intended to avoid detrimental thermal effects.
To this end the International Commission on Non-Ionizing Radiation Protection (ICNIRP), and national bodies such as the National Radiological Protection Board (NRPB), recommend limitations on the localized specific energy absorption rate (SAR) in various parts of the body.
The role of numerical dosimetry is to estimate the SAR from measurable parameters such as external field strengths and total body currents.
In recent years there have been significant advances in the sophistication of the anatomical models available, and in our knowledge of the electrical properties of the body tissues.
Several groups, including NRPB, have developed mathematical phantoms from medical imaging data, such as MRI scans.
It has been known for some time that under certain circumstances SAR restrictions may be violated in the ankle due to the concentration of current in a small area.
In this paper the author presents calculations of the SAR distribution in a human leg in the high-frequency (HF) band.
This band contains the human whole-body resonance frequency and therefore gives the strongest coupling of the body to the field.
The present study uses a finite element model with variable mesh size, derived from a 2 mm resolution voxel phantom of the whole body.
It also uses recently acquired data on the electrical properties of the tissues. (...)
Mots-clés Pascal : Modélisation, Méthode élément fini, Coefficient absorption, Jambe, Objet test, Radioprotection, Membre inférieur, Champ électromagnétique, Dosimétrie, Estimation paramètre, Norme sécurité
Mots-clés Pascal anglais : Modeling, Finite element method, Absorptance, Leg, Test object, Radioprotection, Lower limb, Electromagnetic field, Dosimetry, Parameter estimation, Safety standard
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0233195
Code Inist : 002A08C. Création : 16/11/1999.