Archive
5 postsFilters: category: dosimetry-sar Clear
Model Variability in Assessment of Human Exposure to Radiofrequency Fields
This review examines how variability in computational dosimetry models affects assessment of human RF exposure from MHz to terahertz frequencies, focusing on SAR, absorbed power density, and temperature rise. It reports that anatomical scaling and model choices can drive meaningful differences in predicted SAR (including higher values in children/smaller models), while temperature-rise predictions are especially sensitive to thermophysiological parameters and vascular modeling. The authors indicate that computed variability remains within ICNIRP/IEEE safety margins but argue that uncertainties warrant ongoing research and refinement as new technologies (e.g., 6G) emerge.
Thermal and SAR-Based Limits for Human Skin Exposed to Terahertz Radiation
This conference paper uses COMSOL Multiphysics simulations to evaluate thermal and SAR-based exposure limits for modeled human skin exposed to terahertz radiation (0.1–5 THz). The authors report negligible temperature increases at power densities consistent with keeping SAR below 1.6 W/kg, but note that higher power densities can yield minimal heating while producing SAR values above recognized safety thresholds. They conclude that existing sub-THz standards are not directly transferable to the full THz band and call for updated guidelines, especially for prolonged exposure.
Numerical analysis of the thermal effects on adult with brain pacemaker implantation exposed to WIFI antennas
This numerical study modeled RF exposure from WiFi/5G-type antennas near a 3D brain model with implanted brain pacemakers relevant to Parkinson’s disease. SAR and temperature increases were reported to remain below ICNIRP 2020 limits across modeled conditions, with maxima at a 90° antenna-to-brain angle. Despite compliance with SAR/temperature limits, the authors report modeled thermal strain and tissue displacement that could affect postoperative efficacy, leading them to recommend caution and increased distance from phones.
Auto-Induced Downlink Radiofrequency Electromagnetic Field Exposure at 3.5 GHz With Focusing Near the Head
This exposure-assessment study uses FDTD simulations to evaluate auto-induced downlink RF-EMF exposure at 3.5 GHz when downlink energy is focused toward user equipment near the head. Exposure varied substantially by device position (ear, eyes, nose) and by the precoding technique used. The authors report that the choice of normalization strategy can produce cases where ICNIRP basic restrictions are exceeded even when reference levels appear compliant, motivating a precautionary framing for compliance assessment.
SAR Estimations in a Classroom with Wireless Computers
This study simulated 1 g and 10 g peak spatial SAR (psSAR) in classroom settings where each student uses a Wi‑Fi laptop at 2.45 GHz and 100 mW. Maximum simulated psSAR values were reported to be below ICNIRP and IEEE recommended limits, but desk spacing and multi-user configurations could substantially increase psSAR compared with a single-user setup. The authors emphasize that long-term low-level exposure, particularly for children, remains a concern and recommend mitigation via increased spacing and wired connections.