Aligning Exposure Limits for Contact Currents with Exposure Limits for Electric Fields

Abstract

Overview

The study assesses and seeks to align the disparate exposure limits for contact currents and electric fields as set by the Institute for Electrical and Electronic Engineers (IEEE) and the International Commission on Non-ionizing Radiation Protection (ICNIRP). The limits cover the 0-300 GHz spectrum for electromagnetic fields and specify safety measures concerning contact currents within the 0-110 MHz range.

Findings

• Current limits are inconsistent, particularly between 100 kHz and 110 MHz, prompting a need for revised standards in IEEE's guidelines.
• Significant risks include aversive electrostimulation below 100 kHz and thermal injuries above 100 kHz due to varying rates of tissue heating influenced by skin moisture.
• Recommendations include limiting finger contact with conductive surfaces to 1 second and adjusting electric field exposure reference levels to mitigate the risk of burn injuries.
• Additional safety concerns addressed include wrist and ankle heating from longer-term contact and the potential for arcs between extended limbs and exposed objects.

Conclusion

Proposed adjustments to the IEEE standard could better protect against the health risks associated with both direct contact currents and indirect electric field exposures. Further empirical research and real-world data analysis are advocated to refine these exposure limits and enhance safety protocols.