2. Determination of perception and effect thresholds

Electric and magnetic fields, as produced by power lines, may possibly be perceived and experienced as unpleasant. Low-frequency magnetic fields induce electric currents in the body which stimulate nerves and muscles when limit values are exceeded. Static electric fields from HVDC overhead lines can be directly perceived at high field strengths. Moreover, metal objects such as cars which are located underneath power lines can become electrically charged. Spark discharges or contact currents may occur if an individual comes into contact with the metallic surface of a car.

Research projects

2.1. International Workshop on the effect and perception thresholds of static and low-frequency magnetic and electric fields and contact currents in humans

The workshop was held on 26/27 October 2016 in Munich. Leading experts in this field were present. They gave overviews of the current state of research. The discussion following each overview served to identify knowledge gaps and research priorities allowing to specify the planned research projects. The Abstracts of the workshop can be downloaded from DORIS the "Digital Online Repository and Information System" of the BfS.

2.2. Effect and perception thresholds of static electric fields

An experimental study on subjects will investigate the thresholds above which and owing to which mechanism of action, electric fields are perceived and above which values the perception is experienced as annoying, unpleasant or painful. The presumed perception by means of body hair will be tested. Individual differences, age and gender dependency as well as the influence of external factors such as temperature, humidity, ionisation and clothing will be considered.

The study "Determination of human perception threshold in static electric fields from high-voltage direct current (HVDC) transmission lines" is currently conducted at the RWTH Aachen University. The study planned here is intended to validate and extend the findings.

2.3. Effect and perception thresholds of contact currents and spark discharges in the case of high-voltage direct current and high-voltage alternating current

An experimental study on subjects will clarify the threshold values above which spark discharges and contact currents are perceived and experienced as unpleasant or painful. The study will provide data on individual variability as well as on gender and age dependency.

2.4. Effects on the central and peripheral nervous system due to low-frequency electric fields induced in the body

The project will investigate above which thresholds electric currents induced in the body by low-frequency magnetic fields may influence the central and peripheral nervous system of subjects under partial or whole body exposure. Influences on brain activity that cannot be perceived subjectively will be measured and perceptible stimuli will be queried. The threshold values at which modulation of neuronal activity in the brain takes place and the thresholds above which perceptions and sensations are experienced as unpleasant will be determined. Individual variability as well as gender and age dependency will be considered. This project is intended to verify the reliability of already existing data and to specify the threshold values only roughly known so far.

Outcome of the online consultation