Progress In Electromagnetics Research
ISSN: 1070-4698, E-ISSN: 1559-8985
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By A. Hirata, H. Sugiyama, and O. Fujiwara

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Biological effects due to whole-body radio-frequency exposure may be induced by core temperature elevation. According to the international safety guidelines/standards for human protection, the whole-body averaged specific absorption rate (WBA-SAR) is used as a metric. In order to understand the relationship between WBA-SAR and core temperature elevation, a theoretical solution or a closed formula for estimating core temperature elevation is essential. In the present study, we derived a formula for simply estimating core temperature elevation in humans and animals due to whole-body radio-frequency exposure. The core temperature elevation estimated with the formula is found to be in reasonable agreement with the computational results of finite-difference time-domain computation incorporated in anatomically-based models. Based on the formula, the WBA-SAR is found to be a good metric for estimating core temperature elevation. The main factors influencing the core temperature elevation are the perspiration rate and the body surface area-to-weight ratio.

A. Hirata, H. Sugiyama, and O. Fujiwara, "Estimation of core temperature elevation in humans and animals for whole-body averaged SAR," Progress In Electromagnetics Research, Vol. 99, 53-70, 2009.

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