A European infrastructure for low magnetic field metrology

Magnetic fields are used throughout electrical mobility, energy transformation, and environmental monitoring, areas essential to meet the European Green Deal aim of climate neutrality by 2050. However, low magnetic fields can leak into the environment and pose an exposure risk. These must also be monitored in the medical sector to ensure adherence to EU Directive 2013/35/EU which sets safety requirements for worker exposure to electromagnetic fields.

Currently, measurement traceability is established via primary standards based on Nuclear Magnetic Resonance (NMR), which are held by a only few National Metrology Institutes (NMIs) in Europe and have a lower limit of 10 μT. As well as a greater access to primary standards, improved techniques are also required to remove the effects of environmental magnetic fields from measurements.

This project will establish a European infrastructure for low magnetic field ranges, developing standards for magnetic fields from 10 μT to 10 mT based on techniques such as NMR, optical magnetometers, and superconducting quantum interference devices. A travelling standard will also be produced, making interlaboratory comparisons easier to perform. Real-time active feedback on compensation coils and monitoring of gradient fields will be used to control interference from environmental fields, making low magnetic field measurements and calibrations more effective.

This work will allow European calibration and measurement services for low range magnetic fields to be established at NMIs and laboratories which are currently not available. In turn this will enable a new generation of sensors to quantify magnetic field exposure and, in addition to supporting environmental goals, provide advances in a range of areas, including quantum sensing, information technology and space applications.