Mar 30, 2007
Worst Case Temperature Rise in a One-dimensional Tissue Model Exposed to Radiofrequency Radiation
Theodoros Samaras, Andreas Christ, and Niels Kuster, in IEEE Transactions on Biomedical Engineering, Volume 54, Issue 3, pp. 492–496, March 2007
The results of the study have shown that, at least for the 1-D model, the old IEEE standard was more conservative than the ICNIRP guidelines, i.e., if the basic restriction for SAR of either was reached, the former would result in a lower temperature rise than the latter. Fatty tissue can act as an isolation layer, leading to higher temperature rises in the tissue layers on either of its sides, depending on the electromagnetic energy absorption pattern. The obstruction of heat transfer from the model to the environment leads to a temperature rise in the skin, irrespective of the plane-wave frequency. The maximum temperature rise recorded in such a situation is up to 5 times larger than the one reached in the case of heat exchange with the environment, but this is largely attributable to the enforcement of the adiabatic conditions themselves rather than the electromagnetic energy absorption. The maximum temperature rise was 4 decree for ICNIRP values at 2 W/kg averaged over 10g and 3 degree for 1.6W/kg averaged over 1g. Therefore, special care must be taken under exposure situations which impair local heat transfer.
