Specific absorption rate and radiofrequency current-to-ground in human models exposed to near-field irradiation

To expand our knowledge of near-field radiofrequency energy absorption in occupationally exposed workers, we used coffin-sized calorimeters to measure specific absorption rate in full-size human models. The models were subjected to near-field irradiation at two frequencies at an outdoor groundplane facility. We also measured radiofrequency current-to-ground in the models to supplement a previous study at 29.9000 MHz. The results have enabled us to construct a frequency-independent mathematical relationship between specific absorption rate and radiofrequency current for the given exposure system. Moreover, the results show a favorable comparison to radiofrequency radiation dosimetry handbook predictions of average specific absorption rate when only the vertical electric field (E-field) component is used to normalize specific absorption rate. Once determined on a case-by-case basis, the use of specific absorption rate vs. radiofrequency current curves for any exposure system or condition could be a simple and quick method to determine onsite compliance with specific absorption rate-based exposure standards.