Abstract
The external field strength according to the international guidelines and standards for human protection are derived to prevent peripheral nerve system pain at frequencies from 300–750 Hz to 1 MHz. In this frequency range, the stimulation is attributable to axon electrostimulation. One limitation in the current international guidelines is the lack of respective stimulation thresholds in the brain and peripheral nervous system from in vivo human measurements over a wide frequency range. This study investigates peripheral stimulation thresholds using a multi-scale computation based on a human anatomical model for uniform exposure. The nerve parameters are first adjusted from the measured data to fit the peripheral nerve in the trunk. From the parameters, the external magnetic field strength to stimulate the nerve was estimated. Here, the conservativeness of protection limits of the international guidelines and standards for peripheral stimulation was confirmed. The results showed a margin factor of 4–6 and 10–24 times between internal and external protection limits of Institute of Electrical and Electronics Engineers standard (IEEE C95.1) and International Commission on Non-Ionizing Radiation Protection guidelines, with the computed pain thresholds.
Highlights
This study investigated peripheral stimulation thresholds using a multi-scale computation based on a human anatomical model during uniform magnetic field exposure for the first time in the context of revisiting the protection limits of international standards/guidelines
Computed internal and external field strengths were compared with the limits indicated on IEEE standard and International Commission on Non-Ionizing
Radiation Protection (ICNIRP) guidelines for human protection in low frequency (300 Hz to 1 MHz), in which stimulation is attributable to axon electrostimulation
Summary
Limits or restrictions for non-ionizing electromagnetic field exposures were developed and published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) [1,2] and the Institute of Electrical and Electronics Engineers International Committee on Electromagnetic Safety (IEEE ICES) Technical Committee 95 [3,4]. These guidelines and standards are set to protect from stimulation and thermal effects, which are the lowest exposure levels that can cause adverse health effects, protecting against any other effects. This work focuses on the electrostimulation effect at intermediate frequencies (300 Hz to 1 MHz)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have