A portable meter for measuring low frequency currents in the human body

Area of Science:

• Biomedical Engineering
• Electrical Engineering
• Human Physiology

Background:

• Human exposure to low-frequency currents can occur through environmental electrical potentials.
• Understanding these currents is crucial for electrical safety and perception threshold studies.
• Existing methods may lack sensitivity or versatility for comprehensive body current measurement.

Purpose of the Study:

• To develop a portable meter for measuring low-frequency currents in the human body.
• To enable sensitive detection of contact currents from perception threshold down to single microampere levels.
• To utilize the body's impedance as a primary sensing element for enhanced measurement capabilities.

Main Methods:

• Development of a portable meter specifically designed for 50/60 Hz contact currents.
• Utilization of the human subject's body impedance as the sensing element.
• Implementation of techniques to achieve an estimated +/-20% accuracy in current measurement.

Main Results:

• The meter successfully measures low-frequency currents in the human body within the range of approximately 0.4-800 microamperes.
• Measurements can be made from the threshold of human perception (approx. 500 microamperes RMS) down to single microampere levels.
• The design demonstrates high sensitivity and is relatively insensitive to current path connection points.

Conclusions:

• The developed portable meter provides a sensitive and versatile tool for measuring low-frequency body currents.
• The unique design utilizing body impedance offers advantages in sensitivity and measurement scope.
• This technology has potential applications in electrical safety, research, and understanding human-electrical interactions.