Safety Assessment of H-Coil for Nursing Staff in Deep Transcranial Magnetic Stimulation

This work investigates the exposure experienced by the nursing staff executing deep transcranial magnetic stimulations (TMS) using H-coil. The safety assessment was implemented by employing the H-coil and realistic human model. The 144 relative positions of the H-coil with respect to the TMS operator body were considered, including the distance and vertical height. Dependence of the magnetic flux density and induced electric fields in the human model were obtained by using the impedance method. Results were compared with the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Regarding the occupational exposure, safe distances of 120 and 100 cm are derived from the ICNIRP reference level (RL) and basic restriction (BR), respectively. At the distance of 100 cm, the exposure level does not exceed the ICNIRP BR, and although the exposure level exceeds the RL, continued exposure is allowed. The findings suggest that nursing staff should stand at least 100 cm apart from the H-coil.